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i I i

I

AUSTRALIAN AQUITAINE PETROLEUM WELL SAFETY PROCEDURES

ONSHORE DRILLING

N. CAMPBELL M. IMBERT

SEPTEMBER, 1981

DEPT. OF MINES & ENERGY DO NOT REMOVE

1111111111111111111111111111111111111111 P01141

AQUITAINE WELL SAFETY PROCEDURES

CONTENTS

1) GENERAL 2) SAFETY DRILLS 3) LEAK OFF TESTS 4) PERSONNEL 5) DRILLERS INSTRUCTIONS CHART 6) WELL VOLUMES 7) DRILLERS RESPONSIBILITIES 8) DERRICKMAN/MUDMAN RESPONSIBILITIES 9) MUD ENGINEER/TECHNICIAN

10) MUD LOGGERS 11) CEMENTING OPERATOR/UNIT 12) EQUIPMENT FOR DETECTION OF INTRUDING FLUIDS

~/OR GASES 13) EQUIPMENT AVAILABLE FOR CONTROLLING A WELL 14) CONCLUSIONS

ANNEXES

I LEAK OFF TEST PROCEDURE II DRILLERS INSTRUCTION CHART III DRILLERS PROCEDURES AND WELL CONTROL SHEETS IV WELL VOLUMES FORM V MUD cnNTPOL FORM VI KILLING A WELL BY 11 DRILLERS METH00 11

VII 12 11 3000 PSI ~!ELLHEAD

VIII 12 1' 3000 PSI/10 11 3000 PSI \4ELLHEA_D

IX 10 11 5000 PSI WELLHEAD X SAFETY CONTROL SHEET XI GENERAL SAFETY RULES

- 1 -

AQUITAINE WELL SAFETY PROCEDURES

1) GENERAL During all operations being conducted on Aquitaine operated wells, the following well safety procedures will be followed. Personnel experienced and inexperienced will familiarise themselves with these procedures so that a well can be efficiently controlled at any time.

2) DRILLS Once weekly kick/blowout safety drills will be conducted by each crew in the presence· of the Aquitaine Representative. conducted before drilling out

the Contractor Toolpusher and Safety drills will also be

the cement in the 13 3/8" and 9 5/8" casing strings. These drills will consist of raising the kelly above the rotary table, shutting the pump down, closing the BOP and circulating at a reduced flow rate with returns entering the mud tank via the choke manifold and degasser.

3) LEAK OFF TESTS Leak off Tests to test the resistance of the formation at the casing shoe depth and to verify the casing cementation will be conducted after 13 3/8" and 9 5/8" casing strings are set. The procedure for c0nducting Leak off Tests and the necessary calculations are detailed in Annexe I. The ~roperties of maximum allowable pressures and mud weights deri·;ed from these tests will be adhered to, or unless otherwise rectified by the Aquitaine Representative.

4) PERSONNEL Personnel of each crew shall be assigned specific tasks during safety drills, so that in the event of an actual kick/blowout situation occuring there is no confusion amongst the crew regarding their specific job assignment. Examole: Driller- at the drawworks controls to raise

kelly, shut down pumps, close the BOP and open the hydraulic valve on the choke line, commence circulation and controlling surface pressure.

- 2 -

Derrickman - at the choke manifold to ensure that return flow of mud is not restricted by closed valves, assuring that BOP is closed and choke line is open and operation of adjustable choke.

Motorman - at the hydraulic closing unit (BOPs) to ensure that unit operates efficiently. Ensure that spark arrestors on motors are working.

Roughneck - on the mud tanks. Ensure that returns are in order and to measure mud tank level.

Roughneck - on the rig floor to assist the driller or derrickman.

It must be assured that the choke line and choke manifold are completely and fully open before re-commencing the circulation in order that the formation is not broken down by sudden pressure loading.

5) DRILLERS INSTRUCTIONS CHART A Drillers Instructions Chart which is self-explanatory, will be provided and must be displayed in the doghouse or any other prominent position in proximity to the driller. - Re.fer Annexeii.

Comments on the Chart 5.1) Maximum pressure admissible on annulus: M. Ad. P The Aquitaine Representative will define the M. Ad. P after each casing job or after any change in the mud weight. This figure will be derived from the Leak off Test, or by making the necessary calculations. 5.2) Maximum pressure on annulus: M.W.P. The Aquitaine Representative will define M.W.P., which corresponds to the service pressure of the BOP or :the burst pressure of the casing whichever is the smaller. 5.3) Reduced flow rate to be used in control: Qr The reduced flow rate Qr, which is the flow rate to be used in. the control of a well during a kick/blowout situation is to be calculated at the start of each shift or after changing the bit. This is to be calculated at half the flow rate normally used during drilling. The new pressure loss (gauge surface pressure) at the reduced rate will be noted on the chart under CCP.

)

- 3 -

5.4) Observation of pressures The observation of pressures on the drill pipe and casing annulus with the well closed in are required for a duration of ten to twenty minutes. These should be recorded minute by minute. After the pressure rises rapidly to a point of equilibration) a slow rise of pressure is generally observed) which corresponds to the gas rising through the annulus mud column in a chimney effect. Reter Annexe III,form for calculations for controlling a well .

6) WELL VOLUMES A form to calculate the volume of mud in circulation will be displayed in the doghouse - Refer Annexe IV for example form. This form must be updated every 100 meters drilled or at the end of each shift if that shift drills more than 100 metres. During the controlling of a well in a kick/blowout situation it is necessary to know the approximate volumes of mud in circulation for the evacuation of gas and treatment of the mud with mud weighting material.

7) DRILLERS RESPONSIBILITIES It often happens that a kick/blowout occurs during the night hours when the driller and his crew are the only people on the well site. It is for this reason that crews must be sufficiently aware of the dangers that exist in drilling into any unexpected high pressure zone. efficient training in safety drills, job assignments and the correct filling out of the Drillers Instructions Chart and Well Volumes form be carried out by the driller, or by another crew member under the driller's supervision. The most frequent blowouts occur during tripping, either running in or pulling out of the hole. Swabbing and incorrect filling of the hole during pulling out, and pressure surges and incorrect mud returns during running in can reduce the hydrostatic pressure,damage formations and induce a well to flow with serious consequences. While pulling out of the hole, care should be paid to see that the well is not Swabbing (balled-up stabilizers or bit) and that the well is filled every 5/8 stands with a volume of mud

-4-

equal to the amount of metal removed from the hole. It is advisable that a small trip tank of 1m3 in volume equiped with a volume gauge is used during tripping out. If this is not available, measurements of the mud tank used to fill the hole should be made every 5/8 stands to ensure that hole is filling properly.

During running in excessive pressure surges should be avoided even at the expense of lowering the pipe more slowly. The mud returns and volume should be checked every 10 stands. To obtain better control of filling a hole while tripping out a pill of 112m3 (6/12 bbls) of heavy mud should be injected prior to starting the trip. The driller is the "man on the job" and must be made to realise his responsibilities to the safety of his crew and to the safety of the equipment and the well. This can only be done by efficient training, commensense and a thorough knowledge of correct safety procedures.

8) DERRICKMAN OR MUDMAN RESPONSIBILITIES Proper control, knowledge and reporting of the mud system and mud properties is essential to an efficient operation. A form for mud control is detailed in Annexe V. During drilling the derrickman or mudman must carry out the following duties: - Take the mud weight and viscosity every

15 minutes. - Measure mud tank levels every 15 minutes.

Take a water loss every 2 hours. - Notify driller and mud logger of any

transfer of mud to other tanks. - Notify driller and mud logger of any change

in volumes (losses or gains) or rheological properties.of the mud.

During tripping (to be carried out by a designated roughneck) - Control and measure volumes of mud required to

fill the hole while pulling out, and to control volume of mud returned during running in.

- 5 -

During kill procedures - Operation of choke manifold by derrickman or a designated roughneck.

- Take mud weight every 5 minutes.

9) MUD ENGINEER/TECHNICIAN

- Measure mud tank levels every 5 minutes. Ensure that everything is in order to commence adding barytes to the mud.

Where a mud engineer/technician is contracted from a mud Company (e.g. Baroid, Magcobar) he will supervise and provide instructions to the derrickman/mudman. He will also provide to the Aquitaine Representative a Daily Mud Report in which is listed the rheological properties of the mud, materials added, relative hydraulic and volume data and daily mud cost. The mud engineer should also be present during the conducting of blowout safety drills, and assume responsibility for tasks carried out on the mud tanks.

10) MUD LOGGERS Where a mud logging Company is contracted to carry out mud logging duties under the supervision of an Aquitaine Geologist the technicians shall be aware of the duties to be carried out in a kick/blowout situation. If possible mud tank level recorders installed with read-outs shall be available in the mud loggers cabin. Equipment continuously recording the mud weight returning from the well is also recommended. Co-ordination and co-operation between the mud loggers and the derrickman is essential. Any "drilling break" should not be penetrated by more than 3 meters and a 11 gas shows and "drilling breaks" should be reported to the Aquitaine Representative immediately. It is preferable to stop drilling and circulate any "drilling break" or shows even if time is lost, than to continue drilling into a reservior with unexpected high pressures which may result in a blowout.

- 6 -

11) CEMENTING OPERATOR/UNIT Where a cementing Operator and unit are located on the wellsite and where a kick/blowout situation occurs, the operator must be called immediately, the ma·chine started and pumps primed. The unit will previously have been hooked up to the kill line. Cement will be readied. Operator and unit will remain on standby until further orders are issued by the Aquitaine Representative.

12) EQUIPMENT FOR DETECTION OF INTRUDING FLUIDS &/OR GASES 11.1) Rate of penetration recorder 11.2) Mud density recorder 11.3) Shale density equipment 11.4) Chramatograph 11.5) Gas detector 11.6) Mud tank level indicators 11.7) Weight indicator 11.8) Pressure gauges 11.9) Mud return indicator

13) EQUIPMENT AVAILABLE FOR CONTROLLING A WELL

12.1) BOP stack - drawing to be displayed for each phase of

drilling. 12.2) Choke manifold - drawing to be displayed 12.3) Lower kelly cock - placed between kelly and Saver sub. 12.4) Upper kelly cock - placed between kelly and swivel 12.5) Drop-in type non-return valve during drilling of the

B!z" phase to be placed at top of drill collars. 12.6) Inside BOP valve to be situated on rig floor at all times 12.7) High pressure circulating head with swivel joint with

chiksan connection. 12.8) Sufficent number of 2" 5000/1000 psi chiksan joints

situated on rig floor able to be connected from standpipe

to drill string circulating head. 12.9) Degasser 12.10) Cementing unit (if on service contract)

12.11) Flare line

- 7 -

12.12) Trip tank of 1m3 (5/6 Bbls) to control fill up and return on trips

12.13) SOT Barytes (For offshore operations, pressure tanks to be full at all times)

12.14) 20T Cement 12.15) 9T Lost circulation material 12.16) One tank of mud in reserve weighted to a density of

1,40/1,50 SG (11,6/12,5PPG)

14) CONCLUSIONS It is nearly impossible to follow any safety procedures by letter as each case has different characteristics. The Aquitaine We 11 Safety Procedures wi 11 however be fo 11 owed as closely as possible. The ultimate responsibility for controlling a well is with the Aquitaine Representative at the well site and with the Toolpusher and Driller of the Contractor Company. It is with this aim that the Aquitaine Well Safety Procedures has been drawn up, to provide information and assistance to the personnel on the well site. It also must be remembered that it is not too soon to stop drilling on the "drilling break", mud losses or gains, or shows, and to circulate or put the well on security. It is much better to lose some drilling time rather than have a dangerous kick/blowout situation occur.

ANNEXE I

LEAK OFF TEST PROCEDURE

. )

LEAK nFF TEST PROCEDl'RE ANNEXE

1) PURDnSE: To test the resistance of the formation at the casing shoe depth. To establish a maximum allowable pressure. To verify the casing cementation.

2) NO~ENCLATURE

- The measured depth is the drilled length of the well bore measured from the rotary table.

- The vertical depth is equal to the projection of the measured depth onto the vertical passing through the rotary table.

- The weak point is the part of the open hole taking up mud when pressure testina. In homogeneous formations~ this point is located just below the last casing shoe.

"Re'' is the burst strength of the weakest casing section. If the mud density inside the casing is hiqher than the one on the outside, the maximum permissible pressure at surface is equal to the smallest value:

_BI _ Z di -de 1~10 10

Computed for each casing section~ Z(m) being the vertical depth of each section end, Re(Kg/cm2) being the burst strenght of each section.

W inj. is the mud weight (expected, measured or real) at which the mud leaks off into the formation.

- E.M.W. is the equivalent mud weight at which the cement or the formation will be tested.

- T.P. is the pressure to be applied at surface either to test the casing or to obtain the required E.M.W. For example, if the well is full of W = 1.15 mud, and if the casing shoe, located at Zs =

1 500 m, must be tested at the E.M.W. = 1.60, the T.P. to be applied wi 11 be:

T.P. 1500 2 = (1 .60- 1 .15) x -,a-= 67.5 kg/cm

- 2 -

I.P. is the pressure at surface at which the mud starts to leak off into the formation or into the cement behind the shoe.

F.P. is the pressure at surface at which the formation (or cement) may be fractured. Formation fracture is always followed by a sharp pressure drop.

NOTA

I.P. and F.P. are measured with the pump running at reduced flow rate to minimize and neglect the pressure losses.

3) PROCEDURE

Pressure test must be done using the H.P. unit, at reduced and constant flow rate. Volumes must be measured and plotted with the corresoonding pressures on the attached diagram.

Ouring the operation, watch the annulus between casings and bleed-off in case of pressure increase. Compare the pumped volumes with the calculated volumes.

-The oump must be stopped:

- either when T.D. is reached. - or when 3 or 4 consecutive plots are located off the normal

pressure increase line. The point of divergence is I.P., -or, if by inadvertence, fracture is reached (F.P.)

- After the pump is stopped, watch the pressure during 3 to 5

minutes for cement and formation tests, and 15 minutes after stabilization for casing test. Plot the pressure drop versus time on the diagram.

- Bleed-Off slowly while measuring the released volume.

4) RESULTS

-A casing pressure test is positive if the pressure is stabilized during 15 minutes at a value hiqher or equal to:

- 90 % of test pressure for pressures~ 400 kg/cm 2

- test pressure minus 40 kg/cm2 for pressures~OO kg/cm2.

- 3 -

- Regarding formation or cement test, make sure that the pressure stabilizes or tends to stabilize after 3 or 5 minutes. This stabilized value will be taken to calculate the corresponding E.M.W.

- The result of any pressure test is given as an equivalent mud weight (W test or W injection or W fracture)

Ex 1 - Cement test

Z shoe: 1 500 m; W = 1.15; TP = 67.5 kg/cm2

W test: 1 15 + 10 x 67 · 5 = 1.60 • 1 500

EX 2 - Leak off test

Z weak point: 850 m; IP: 40 kg/cm2 with W = 1.18

W i nj . = 1 . 18 + 1 01 x 8~~ = 1 . 40

Ex 3 - Unexpected fracture at shoe depth

Z shoe = 1 500 m; W = 1 .15; FP = 85 kg/cm2

10 X 85 W frac = 1.15 + 1 500 = 1.72

- 4 -

PRESSURE TEST REPORT F 15 bis/4 .so R.K.B. ELEVATION ~ MEASURED VERTICAL

WELL RIG DEPTH DEPTH Ground or M.L. M.S.L.

SHOE Zs- m

DEPTH (l)

TOOL ··--DATE OF TEST~ HOLE DEPTH : PRESUMED ,.

WEAK POINT Zi - rro

MUD CARACTERISTICS Type= AV= yp =--- Gels 0/10 · Mud weight

DURING TEST PV = W.L. =-- kg/1 W:

CASING D CEMENT D FORMATIOND

PLANNED ( 1 ~leO ) :

test in j • I Mox. Perm, Press, Estimated W inj. = D 0

TEST kg/ cm2 Desired EMW( 2) = Desired EMW (2)=

TYPE Planned testing pressure : Surf. pressure =(EMW-W)~ Surf. pressure (EMW·W) L 10 10

T. P.- kg/cm2 T. P. = kg/ cm2 1 P, or I.P, kg cJ.

PUMP: PLANNED PLANNED INJECTION LINE: FLOW RATE : MUD VOLUME:

Pumped (or released) Total pumped volume: TIME volume Pressure RESULTS

by step cumulated Total released volume :

Casing Stabilized P. Stab. Time: {Pos. D Result. 0 test Ne g.

zfCsg shoe D ) Cement T.P. = W .test = or lP. = L:"k po;otO

W. inj. = formation F.P. = W.frac.=

test kg/cm 2 10 p (= w + -z-l m

COMMENTS:

-

1) Specify he re Visa:

0 Bottom hole

0 Top of cement

0 Packer or plug 2) F.quivalent mud weight

Reference Note DPRO.'FOR 9 378 '"'" 'Wl2SNEAIPI·RGMN°959004024

- 5 -i""'

PRESSURE· TEST DIAGRAM

• Mud should be homogeneous, cleon and not gas• cut

Well : • Pump flow rote should be adjusted between 50 and 1 OD I mn (m ox, 300 I/ mn),

Measured depth : • Theorical compression is 4 to 5 I by kg/ cm 2 and - by 1 DO m3 compressed,

0 Casing : • Be careful not to confine an air plug in the circuit,

• Release the pressure slowly while measuring return volume.

Shoe measured depth :

~ ::>

"' "' ~ 0.

0. £ ::>

0...

. .,. ..

I I J J I I

Minutes after the pump is stopped

Pumped volume

I

ANNEXE II

DRILLERS INSTRUCTIONS

CHART

ANNEXE 2

COMPANY DRILLER'S PROCEDURES for well control

!DRILLING FAOM LAND OR fiXtD SUPPORT!

WELL I """ I ::::'.:: ~::• I Mo' .,.,,, I Mo~ .. :."• I ------~j __ .~:_:~ ____ _LI· .. ~··_·"-'"·~··"-' ----~~-p~·-----L--~----------~

1. At every bit change or crew change :

Cucu!.-Jte oil bottom /01 5 mflluft.•s at tt:duced flow rate and tecord pressure/ass fP, ,J.

2. If any of the following occurs during drilling, coring, or circulating

UJC!t.H.IW.' m dn!lim; mrt:

rn:tease of 1/.ow across .. \hale ~hakffr nr.:t£:215£! m pd ft:vef

Gas cur mud !Ctl.!<t!:.e m mud chlonde cunU:nt

fl,utwl Ot IIJ/,JI mud IOSS(!S ,,,

I I

l• P1ck. up k£•1Jy unt1l T.J 1S 3 If aoute rorary table .J • Shut uff mud pump · ctJeck tor well/low or lm.st:s. • NotJfy operotw and contfiJcfOr l uu! fJV\flt:r

r---------.----~

~-~==-=-·-, W_H_l _ _'::__S_~~-~-.-lf---, I H Wf t L ISH OW!NC ~ ~----IF-W_£_ll_I_S_l0_0_S_IN_G ___ ,

r

o III!SUITW Llnu/a//()1/ ~ 0JI£fl tin: L"lrUAt• /me flit' chv/<.t' 1 Lacuid/L' ,If tutiu(t'<i lluw rott:

• Clit.'CA for mull /11( tuvel, mud I lvt'lrJhl. one/ :,!wws b£11lil fully op~::n Cnt:ck for los:,r;s

• lk~.!lff!U OJWfdiJOfJ!:. • Close I fir {J,u; type W,11r !01 ur(fers

, ;!u,>/y<lu>ct/n <f,ui'"'"J/U<HCI!,nu<y '------------...J <111d rinl! fJ/fn f!r~s~ul~ for lb 1/Jifl~

lf CASJNG PR£SSVR( AEACHL5 P,,, I l lf CASJNG PRESSURE IS LESS THAN P," I

TOTAL 121

()/'~" •·lpt>l old<'> I o,!, ~"iJ •l>luol~"~ "~·, ''•'11'•' I I' ~I ll'd"r'·,/(,,,.,,_.1< JOilv'l<l >~1 /<,l/•.1·•1~<>>.s(<>J, IJ>•If·l~,""' ~')--~//,I'~,

i..Jv '"./ 1"1 ,. < ~·~ "' < ~, l>j /"<', ,,,,, . .s> I•• f> 11•>! 1"< \ ,_,.·~ 11 I~>' lh"n 1-, ,.

Qn· CiHmq pJt•Hure must 1/t'vN 01• tuyhn !IIJn ?, .. I (1) /11/fw t,o',>• ,,f /<ol·i//t,•,,t'o /,1/ 1•/1 /I•<' Jl'<•,lo,. ,•.of/, !'"''', ,,,•,. 11. I•· A<<·jl/!<t: h· .. ·t dl H.tiHe 111/lt' Wt'/1 11 /{,.,\•1"/ < ·<>·1: 11 m,,~ u,d,t lit.! .. ,,,,,,. '"''' "",,,/ )(., '" ,;,,,. r •!I I\ :1

(2) P~, can tn• ddNmlm·dtto~'f1/y . .-.ln•npvll•iHIIIJ ~~ ~/JI/td. /<(>~IJ tCJmiJ>Jf Ci:nlfi!JI''('iHHt' eqvJ/tcJ P,, . S

ftJr" /JI:I!Oil /if h·"' llllfWI•:l l/J1• 1/ul•rl ~!lflt' !llt'5lUit• 5/Juv.</ b(• du\·,,ru /lot P., '"'"'ii<Jkd .JlJv~t

3. If the well is not taking mud on trip, or flowing while out of the hole :

If HIE WHliS STABLE

Unlt!SS othl!fWIH' notlfit.'d

Hun ptfJI! !Jack ro bor1o111. /11 Urst• of losses kut•p ann,;hts lull d poss!IJie Resumf! C!fcu/,J/1119 ill recluc:ed 1/uw fiJff!, eventually Ufldt·r control at consfilfl/ DP jJff!!:>SU!e (CJuf!Ofl

~omf.! g;ts may etlfel rhe wt·ll !Jure)

~---------------'

Stop roppmg Ch~:ck lot well flow or IOBt:s

Notdy opNator and contracto1 Tool pusher

1r TH£ W[lL IS FlOWING 11 1111 ltUW IS •M 'IIA'rl"-1•

,f l!tl MvUI.AI'- IHAI 1<! ~

Mo~~ 1.' U/) r/111111/dt· {J,n/.. fJI~'l~/11<.' Voof, I *r------------'--1 111t.illffS/IIIIfJ

Wtf/, muumum delay, run f)lpt! f,ack. to /Jou,un. Ctwck mud gom

On bottom ptOCI'C'd us .JIJ(H't: ~ 2

~--------------_j

S rop tflppmg. Clust: the tx1g typv. S'luwly 1'/(1.,~· (lit' £/HI/..t•

Wisl! !or ordt!fs IJIL·vrl olf d c.!Sfllg pressurt: rt·,tchex P

NOTE Tfw Opt.•rutor Supervtsor m11st f11/ up the IJbOvt! shmlowt..•c1 spt~i:es as ollt.•n us llt'L't.•ssmy.

ANNEXE Ill

DRILLERS PROCEDURES

AND WELL cnNTROL WORK SHEETS

- 1 -ANNEXE 3

Driller's procedures and well control work sheets

IMPORTANT NOTES

The drilling crew are often alone at the well site when a well kicks, and the driller must act quickly and correctly. It is therefore essential that he be given simple, clear orders that he understands perfectly.

The "driller's procedures" proposed here apply to onshore or f1xed platform drilling. When drilling from floating vessels these procedures must be modif1ed to take account of the special circumstances relating to the sub-sea BOP stack, the type of vessel and its environment. These factors are discussed in Chapter 7.

The control procedure given here cannot be guaranteed to succeed unless the closed in annulus pressure is lower than Pin and the bit is close to bottom. Chapter 8 discusses the procedures required when these conditions cannot be met.

The assumption that the gas bubble is at the bottom of the hole is only justif1ed if the kick is detected immediately (for example by a drilling break).

An acceleration in return flow rate or a pit level increase often corresponds to the expansion of a gas bubble as it nears the surface. If this occurs one mud cycle after the bit gets on bottom or after making a connection, it is generally a small bubble which can be circulated out without back-pressure (well wide open or on a large choke). If not, the well should be closed in, the drill pipe pressure determined, and, if it is not zero, the normal control procedure put into action.

It should be noted that the presence of gas near the surface will increase Pa to such an extent that it may exceed Pin without fracture pressure being achieved at the casing shoe.

If an oil-based mud is used, any gas entering the well bore may dissolve completely in the mud. In this case the kick may not be detected until it almost reaches the surface, when the gas is liberated and the kick reveals itself violently. This dangerous situation is handled by closing in the BOP's and disposing of the gas through the flare line.

- 2 -

DRILLER"S PROCFDlJRl'S ANI! WELL CONTROL WORK SHEETS

DRILLER'S PROCEDURES

See Table IV

6.3. NOTES ON THE DRILLER'S PROCEDURES

6.3.1. Initial allowable casing pressure (P;11 )

The company drilling supervisor will set the initial allowable casing head pressure P;" after setting each casing string. after any change in mud weight or when any new information on formation strength becomes available.

It is not possible to lay down a standard procedure to be followed if P;11

is reached, and the drilling supervisor must therefore select a procedure suited to the particular circumstances and ensure that this is added to the "driller's procedures''.

· 6.3.2. Shut-in period and pressure measurements

A 10 to 20 m in shut-in period is normally sufficient to obtain the stabilised drill pipe pressure.

After a rapid rise to the stabilised pressure there is generally a period during which the pressure rises slowly and steadily as gas bubbles percolate upwards in the annulus and the mud in the well heats up.

The drill pipe and casing head pressures should be recorded every minute, using sensitive pressure gauges with a full scale range of no more than 1.5 to 2 times P;n·

6.3.3. Maximum casing head (annulus) pressure (PmaJ

The company drilling supervisor will set the value of Pnwx at the lower of the working pressure of the BOP stack or the bursting strength of the casing (see Chapter 2, Section 2.2).

3 -

TABIF IV


lDRILUNG FROM LAND OR FIXED SUPPORT)

WELL:

1. At every bit change or crew change :

Circulate off bottom for 5 mmutes at reduced flow rate and record pressure loss fP, ,).

I l-------1 . "~· {-------. I'"""' I !low

role

2. If any of the following occurs during drilling, coring, or circulating :

IF WEll IS STABLE

• Resume circulatiOn. • Check for mud pa level, mud

weight, and shows. • Resume operattons

• Increase in dnllmg mte • Increase of flow across shale shaker . • Increase in ptf level. • Gas cut mud • Increase in mud chloride content • Parttal or tot<1/ mud losses tu.

t kelly until T,J, ts 3ft above rotary table. I

f mud pump - check for well flow or losses. peraror and contractor Tool pushf:f

IF WEll fS FLOWING

• Open the ct1oke /me, thl-' choke

hemg fully open.

• Close thv bag rype.

• Slowly close tl1e (-{lOA e and record casmg end dnll p1pr: pressure for 15 mmuw~

IF CASING PRESSURE REACHES P,..

follow rhe mstructmns here under

Calculate PR 1 a~ follows

• nort the slab•lued dnll p1pt p1e~wrt

---------------· • add thtprtl:.utelosslt! rtauc~allow!ate

------------- • add the l!tp ffld'9"'

IF WELL !S LOOS!NG

Circulate at reduced flow rate

Check for losses

Watt for orders

!;,

TOTAL f2l


IF THE WELL IS STABLE

Unless otherwise nott!ied: Run pipe back. to bottom. In case of losses keep annulus full if pOSSible Resume circulatmg at reduced flow rate, eventually under control at constant DP pressure (Caution some gas may enter the well bore)

Stop tripping. Check for well flow or losses Notify operator and contractor Tool pusher.

IF THE WELt IS FLOWING

Male. e up an triSide back pressun• vulvL in drill string

With minimum delay, rurr ptpe back to bottom. Check mud gain

On borrom proceed as abO\'e ~ 2.

If TH( HOW !S INCH! A!ll~(, OA

If THl MUO (,A IN Hf A(;H{ ~

S rop tnpping. Close the bag type. Slowly clo~u the cf1of...e Wait for orders Bleed off if casmg pressure rNJc/ws.P,

NOTE : The Operator Supervtsor must ftl! up the above shadowed spac~:s as often as necessary.

- 4 -

DRILLER'S PJWCEDUJU·:S AND WELL CONTROL WORK SHf'ETS

6.3.4 Keeping the well full while tripping

Depending on circumstances the annulus will be filled after each stand is pulled, or at the most after five stands are pulled. The cumulative volume taken by the well should be calculated every 5 or 10 stands, and should be compared with the records of previous trips.

It is most important to measure the volumes accurately. If the drill pipe tends to pull wet it should be slugged with heavy mud before pulling out.

.#,"

6.3.5. Kick occuring with no drill pipe in the hole

The pipe should be run in the hole immediately with a back-pressure valve in the first stand, even if the flow is very slight. The subsequent procedure is the same as that given for a kick occurring while tripping.

If it is impossible to get any pipe into the hole, close the blind rams, ensure that the pressure does not exceed Pmax and wait for instructions.

6.4. WELL CONTROL WORK SHEET AND PUMPING PRESSURE PLOT

See Tables V and VI

6.5. REMARKS ON THE WORK SHEET

The well control work sheet is usually completed by the company drilling representative and the toolpusher. The work sheet shown in this book is a composite of various such sheets used in the industry.

Calculation of circulating volumes.

To avoid making any mistakes it is advisable to prepare sketches of the well and the drill string.

It is also recommended that the times and pump strokes required to reach particular changes in section are calculated in advance. The pressure changes occurring as the weighted mud reaches these points can then be anticipated.

TABLE V. \VELL CONTROL WORK SHEET

WEll WELL CONTROL WORK SHEET WRITER

DATE

I _ BASIC DATA Ill_ CALCULATION tiF CONTROL PARAMETERS

DEPTH SELECTED PUMP CONTROL PUMP RATE INITIAL MUD RfOV1RED MUD WEIGHT wr =WJ•10Pdt•S = ____ .u~- _.._ wr = WEIGHT

z MEASt.X<€0 VERTICAL

N' a, PUMP SPEEO PUMP PRESSI.JRE SEJ"ORE BARlfiNG IJILIO ffi1 PLJ•PdJ•S = -----·----- ··----- -PRJ = ____ .kglcm1

MD! m) Z(m) LINER U'fERS/SfflOKE ( f I mn) ( Str/min) wJ (kg{ll PUI-f? 1"!1€ S~ WHEN THE WEIGHlfO PRr Pl 1 x .:!!_!__ ; _____ X~ -PR, = ---- kg!cml MUD R£ACHES Tt-E Bll Wl ------·

-PUMP PRESSVRI: DECREASE VERSUS t.PR = PR 1 - PR r ------ -

aRQJLArro PRESsu:!E LOSSES R>R Or ANO w1 CIRCULATING PRESSURE LOSSES = . ---- _.,. .Lf'R = _lo;gJcml/kgll INITIAl

IHROOGH FOA0rANDW1 tNCRlAStNG WEIGHT OF MUD Wr-WJ ..

DRill PIPE THROUGH CHOKE liNE AND MANIFOLD

SAI'"ETY

NOR,....Al DRILLING KICK ASSEMBLY PRESSURf (CHOKE FULLY OPEN) MARGIN A = 4.2 ~ = i.2 - - A = ___ kg!! Plt OUANTITY CF BAAilE RECUREO

Cl~ CUlT ANDUNESlO Apc1 ( kg/cm2) 4.2- wr 4.2 HP PUMP PdJ s

lips (kg/cm2) THROUGH oNE uNE I THROUGH TWO uN:s

TOTAl WE!G!-ll C1' SA~IT£ B V tot X A = . -- ____ x __ -- - B = ---'• Plo t kg/etnll PL0 • Lips i li!glc:ml) I kg/eml I

t-Kl (F M\..10 cYCLES liJ BE U'-ED ~ -~--·

INCREASE IN M\..0 VvfiGH'I. P8" CYCLE Llw= ~-~ = --.-------- -~ - l:J.w :: _ kglcm2 I CYCLE .. N ------

(Jl

11 _ CALCULATION OF VOLUMES AND PUMPING TIMES 9AI.llliNG RAT€ c = -A.!_Q_J_ = ------ _x_- --- -- . - c = _____ kgtmin

N ------

ANNULUS SPACES LENGTH I AAN~US T01AL DRill STRING I lENGTH llmERN~ l lOlAl 1"\.JMf> PRf.SSLf!E: WHEN "'4U0 W2

W2 :WJ• f':.W =-- PR2 = PR1- LIPR x Llw : ___ kg/eml

--- VOLUME ANNULUS VOLUME INTERNAl P.EACHES THE an DIAMETERS I m I PER ).£TER VOlt.J.1E 00 1e ID f m ) PER METER VOLUME

----. f.fJm I I LITERS l OR l.etFT 1f1ml t UT"ERS l Plft·if" PRESS~ 'M-EN j...t_[: W)

w3 =~· t1w --- PR3 = PR2- LIPR x Llw : ___ kg/em2

F<~ACHES THE M

HOI..E_xrx; ___ ---- --·- ----- OP~-- ._x ____ ------ ----- IV_ Calculation of pump pressure at the end of the control period __ ,oc __ --- --- -- _x ____ ----- ---- -------'""----- --- ---·- -

__ , __ --- --- , __ , ___ rn~oeoMuM ~-- ~- '"•~~ '•fr•' UNEk --dl<:_ __ ------1---- ------·

oc __ , ___ ----------PRend = PRr + Apc1 X.::!!.!_ :-- + X--·- _, OP_ -1---- --- ----- --~---·------- ----

cASN::. __ x oc __ ---"--------- ----- THROU:~ iWO liNES -- -+- PRend=--- kgfcm2. ---___ xoc __ --- ---- ---V_ Checl< that open hqle is not fractured with the chosen· S · margin ---• DP--··- -- ------ INTERNAl. VOLUME.~--··----- ... Vdp = ___ p

_____ xOP~- ----- ___ , --~ -~~- = ___ f

ANNULUS VOlUME .. ..... -····V a llpc1 x:!'::!.:.- <:: Wtrae Wt.ac =---kg/£ MERNAl VOIJJME OF MUD IN PITS 10 BE WfJGHTED. _ ...... ___ = _____ f Weqv : Wr + 10

Zweok point w, CHOKE liNE - ·--· ------- --- ··- ----

THROUGH ONE liNE \'Veqv=--4-10 X--= ANNUlUS VOlUME V a TOTAL ~WoE TO Be WEIGHTED .... V tot : _____ f I CARRIED 0\-£R ON THE RIGHT J { EXClUDING lf-E RISER J THROUGH TWO LINES Weqv =-+ 10 ---- X--=-------

suRFACE ro err I "" TO suRFAcE TOTAl VI_ Weighting- up the mud in the riser {before opening the BOP's)

CIRCUlATING 't'OLUME -------- -·---·---

~=---·--- ~=---=-- V lot PUMPING T !ME: {minI --=---=- --- RISER VOLUME lv,=--l I o, a, a, NO OF PUMP STROKES ~---- V a V lot w -w1

.Ptstr- ----- .Pis!-;=--·-· - .flslr =--=---- REQUIRED WEIGHT OF BA RITE Br = Vr X 4.2 4_~ _ Wr :. --X 4 .. 2 4

_2

: __,.._ Br =---kg

-·

NBo SHADED AREAS MUST ONLY BE FILLED IN FOR FLOATING RIG

1.

2.

3.

4.

5.

6.

- 6 -

DRILLER'S PROCEDL'RES AND WFLL CONTROL WORK SHUTS

TAIJLE VI

PUMPING PRESSURE PLOT FOR HIE PEIUO!l DUIUNG WHICH

THE WEIGHTED MUD TRAVELS FROM Sl'RF·\CE TO THE lll'l

Oo the vertical pressure axis plot the value of P RI'

For the second cycle P Re'" etc.

On the horizontal pump strokes axis plot the number of strokes required to pump the mud from surface to the bit. Draw a vertical line from this point.

On this vertical plot the value of P "''for the second cycle P,-' ... etc.

Join the points plotted in I and 3.

Select the number of pressure steps desired and calculate the number of pump strokes for each stop, plot these values on the horizontal axis and draw a vertical line from each point

On the line drawn in 4 read olfthe drill pipe pressure to be maintained from the start of each step and write these figures on the plot. If it is desired to minimise the pressure overbalance at the formation, the drill pipe pressure to be maintained should be the average of the pressures at the start and end of each step. In this case the difference between the two pressures must be less than twice the safety margin (S) used in the calculations.

PR,kg, pn: -l-H-'- _ _j __ i i _ _LI : J ' 1-·- __ ,,. L L ' i

·· r : -;- j ..... L .. !-· ;_ !·' '

+ 1-.. ---· --- : ' ! . ···-- - i

--· T -~~ I --;- ... ...... .. •

.

·--- t:- 1·----· r- .... ....... ..... , .. , ----:·-· - ... ------ .... : ...... ·--- ·-·····- i ! ..._ ... c. .__, ___ . -- ,.--

. : .. . -·· i c ' ! +---"- r··--- i--+- - -· --· -,

--r--+- ·-t· !- r'-Lj. :-' J L i ' ! ... r ',J .. !-· - !-- j I· : ---. ' !

1- ... -l. . ·t-· . ··-·--- I '- ------ ___ i .. _, j· I ' I

.... f-- : .......... - ; !-· ) ... ; : ' ;-- -·- ! ----

! i i j-~L ; ···--'

-t +- ·--·~ r----·,- ----- H- i-'

i + + L i I ! ... ....... ! .. --'

I;

!-++ !+ -··t .. + r·-- !·--·L j : !

t----1-+ !-+- __ L_ -! •••. j •• _ _. __

1-· ! i

.... L .... L .... i : ~ -··'· i · I

t-----;---I

. ... j I

.... (.. ; - ~- __ , . ._, .. ··--- -r •... !. ••. ' I ; .. , .. ,. '

1- ··-···· ~+-:- -+· + f + ; : P,Uo/JP ~tr9ke~ ---j- .. , , I+· --l-~ ·-···· · + ! '- -;- -i-J . ! + t!m~.=~~;~ L_ ' ! .---L..~--1~

I I I - 7 -

DRILLER'S PROCEDURES AND WELL CONTROL WORK SHEETS

Calculation(){ circulating pressure at reduced rare.

If the circulating pressure at the reduced rate has not been measured, an approximate value can be obtained from Fig. 37, using the circulating pressure at normal pump rate as a reference point. •

If P RI was obtained directly using the initial annulus pressure method:

PLI = PRI- (Pdl + S)

circularing pressure kgj,cm~

300 250

200

150 /

i/

V I

I I 1/

I ~~~ V I{ I' V I I

1/ I / I I V V V I / I V I I

100 90

70 60

50 45 40 35 30

25

20

15

0

I .L

L

I I

I

V

I 11 I I

1/ _/_ jj_

L I

V !J

I If j

V 1/ lill V

;. V I J

il w I ,j I I

r- I--i -r- I--

V I V h I I I

~ I 1/

ll I

lilll I

1[}1 I lit

lJ I I) I

I ) I

lY VI I

IJ I I pumping rate I/

300 400 50o6oo : eoo: 1000 : :t~oo: :2 oo 3000 40 Ol1t 10 res/min . . . . . . pumps1=2eea

I 9

I

12 15 io · 5o 6o 8o 100 12o strokes/min 20 25 30

Fig. 37. - Calculation of circulating pressure (P Ll) at a reduced pump rate.

This chart may be entered with either pumping rate (litres min) or pump speed (strokes m in).

Example. Circulating pressure 150 kgjcm 2 at 2 000 litres/min. I. Find the point corresponding to 150 kgjcm 2 and 2000 litres/min. 2. Through this point draw a line parallel to those shown on the chart. 3. For a pump rate of 1 000 litres/m in using the normal circulating path, the

circulating pressure would be a little over 40 kg/cm 2 •

Weighting the mud. ·

Barite should be added to the mud at a constant rate. The best method of controlling the· procedure is to use a pneumatic silo and mud weight indicators.

- 8 -

DRILLER'S PROCEDURES AND WELL CONTROL WORK SHU~TS

The following procedure may be used if two circulating tanks are available: (1) While circulating the original mud using one of the circulating tanks, weight up the

mud in the second tank to the density required for the first cycle (W2 ) at the rate calculated. This gives the opportunity of adjusting the equipment to the required weighting rate.

(2) When the weighted mud reaches the density l¥2 , switch circulating tanks and note the pump stroke counter reading.

(3) Reduce the pumping pressure following the firSt line on the plot. Check the mud density in the suction pit to verify that the weighting-up rate is correct.

(4) When the weighted mud reaches the bit, keep the pumping pressure P R2 constant until the mud of density l¥2 has reached surface and the mud in the suction tank has reached the next higher density l¥3 .

(5) Reduce. .. the pumping pressure following the second line on the plot. Repeat steps 3 and 4.

NoTE. In certain situations the kick is circulated out before weighting up the mud, but the same weighting procedure is followed in either case.

6.6 EXAMPLES

Two completely different situations will be examined: a deep onshore well and a shallow well from a f1xed platform.

Example 1: Onshore well.

BOP's 10000 psi WP.

Well depth, Z 6120 m 9 %" casing shoe at 4 534 m 7" liner shoe at 5 688 m Hole diameter 5 3

//

Mud weight 1.76

Equivalent fracture density (leak-off test) I .90. The drill string comprises:

910 m of 5" 25.6 lb/ft drill pipe 1 I79 m of 3 1//' 15.5 lb/ft drill pipe 3 864 m of 3 1/ 2 " 13.3 lb/ft drill pipe

I 67 m of 4 1 I 2" OD x 2" ID drill collars.

A control rate of 400 litres/min has been chosen (pump speed 102 strokes/min at 3.92 litres/stroke).

The circulating pressure measured at this rate was 70 kg/cm 2.

Upon closing in the well after detcting the kick the stabilised well-head pressures were:

Pd 1 = 28 kg/qn 2

P. 1 =57 kg/cm 2

A safety margin of 15 kg/cm 2 will be used.

9

FIRST EXAMPLE


{DRILLING FROM LAND OR FIXED SUPPORT)

WELL; , ...... :::J% 0"'~':;!~' .::>G8::ltnl M''w"'"' 1.7bJ;~ •- "'~ UpciU..:Ion: -· X ..!.":. :'56$1 8m lMk•t>lftNl -·

.,,, .• , w'""' 1. '3 '· . 85""''""' oo1r ... liu~I'Y•N>r \

• 1. At every bit change or crew change :

Circulate off bottom for 5 mmutes et reduced flow rate and record pressure loss f':,).

,-- 17~.~~;1·- .. c ~-= {'' -~- ~" ;.-~ v:-~ .), ';j 2, '' ·--~10l,,l p (!?:~i~l flow ,.. . H

~" nrok• mii'M.I~ ·• < • '


• Increase in drilling rate. • Increase of flow across shale shaker. • Increase in pit level. • Gas cut mud . • Increase in mud chloride content. • Penial or total mud losses m.

t • Pick up kelly until T.J. is 3oft above rota!"'/ table.

I • Shut off mud pump · check for well flow or losses . • Notify operator and contractor Tool pusher.

~ 't ~ IF WELL JS STABlE IF WELL IS FlOWING IF WEll IS lOOSJNG

- Resume circulation. • Open the choke line, the choke , Circulate at reduced flow rate. • Check for mud pit level, mud

being fully open. , Check for losses. weight, and shows.

• Resume operations. • Close the bag type . • Watt for orders .

• Slowly close the choke snd record casing and drill pipe pressure for 15 minutes

~ ... I IF CASING PRESSURE -REACHES P," I J tF CASING PRESSURE IS LESS THAN Pm f

follow t~ instluctions here under . Aecoo1 ttm pres&vre ! ~~ '57!ilvm~

~~ e;~"ss1,;~:;d to ~f£* ~ces>llce Caicutale P111

u follow1

, nor. tt.. r~bt/Q.O dn/1 fNIH J~~ttUUr• P., -~~~~am~

~eep c.mm!'~ :r~~~ ~~~~ 1 IH/d tM IJIH$I,JfW luu If Fftiuc.d flow r.tl p

11 • 70 /vmL

.~c; c c;i,l ~l-t!D'll" , lddtMtnpi!Vrgm s .;~ 5.A<'1. I='

~~~·'· ·~Mo1~ oo ocder:£ TOTA.l/2J P., .113 .,/vnl"

• Bi2''f to l'"mf' o. ,\"'(\ ot'tlfC>Yj m11d. - Op1n •dJUillb~ Chok• •nd wrntlf/IMOUS/y IIM pump 11 trfftJCfri flow filii. •rJfU$1 chC>.II.f ID m11n111in 11 f;Dnlflnl ptfiS/Jf/1 ;o lUll lo P111 Do flDI lllh Clfl Dl C/IS/119 pi/IS$/JffJ l$111 liS tlm ptfJWfl ll MU~~~ P -•,

I The casing pressure must never be higher than Pmu I ( t j fn th~ case of tofaf losses fill up th.e annulus wtth mrrd or water m order to keep th~ level 1ft surflfctJ. If t111: we 11 JS flowmg. close Jt m as md1C1J/ed above. JJnd w;ur for msttuCtlons ;.

(2) P~, ~JJn be determined euily: whtm pumpmg is stilrted, *.aep const1nt c11sing pressure equ•lto P., + S fo1 IJ peflod of few minuttn The Slllnti pipe pressUIIJ should be close f(' the P,1 CIJ/I;ulllted tbove.


. Stop tripping . Check for well flow or losses. Nottfy operator and contractor Tool pusher.

,r t IF THE WHL IS STABLE IF THE WELl IS FLOWING :: ~=: ~L:;G~I~N~ER::~:G. OR 2 m

~ OA

Unless otherwise notified: IJ GAS FlOWS Make up an inside back. pressure valv

Run pipe back to bottom. In case of in drill string. losses keep annulus full if possible.

With minimum delay, run pipe back Stop tripping. Resume circulating at reduced flow to bonom. Check mud gain. Close the bag type. rate, eventually under control at Slowly close the choke. constant DP pressure fCaut1on: On bottom proceed as above § 2. Wait for orders. some gas may enter the well bore}. Bleed off if casing pressute

reachesP_.

NOTE: The Opetator Supervisor must fill up the above shadowed sp11ces liS often as necesSilry.

VVt.LL LUNIKUL WUKt\. ~Ht:tl. 1 IKZO,I tAt\l'vtt'LC

WEll ~ WELL CONTROL WOHK SHEET WRITER

DATE

I _ BASIC DATA Jll_ CALCULATION OF CONTROL PARAMETERS --

DEPTH SELECTED PUMP CONTROL PUMP RATE INITIAL MUD REQUIRED MUQ WEIGHT w, •w1•IO Pdi'S .1l6.n~ ._i_83 -w,

MEASURED VERTICAL WEIGHT

z G. 0 .-115_,.,=, a, PUMP SPEED PUMP PRESSURE &FORE BARITING t.IUO PR1 :Plt~":pdl•S :~8.+1_0_,+.15_

MO( m) Z(m) N' liNER liTERS/SfROKE ( f I mn) (Str/min) W) (kgfiJ -- PRJ

MW_ ~G12D ~ _!lE__ __3_" _ _3~1_ -4-00_ AD1,_ ].16_ PUI-1f> PRESsum;: WHEN THE WEIGHTED PR, :PLI X..:!!.!..__ ,]O .. x 1¥~ -PR, =B__I<g/ctnl MUD Rf:ACHE:S THE BfT Wl

- - -· ·- i---=---~ _+t3. ---13. CIRQJL.A.TIN3 PRESSl.f*: I.OSSES FOR Or AND W1 INITIAL CIRCUlATING PRESSURE lOSSES

PUMP PRESSURE DECREASE VERSUS llPR , PR 1 - PR r ~ ~ = 5:llc.g!cm2 /k.gtl THROUGH

~-FOROrANOWt INCREASING WUGHT OF MUO Wr-W, --t. g::.-- ::ere;;

DRill PIPE THROUG~i CHOKE liNE AND MANIFOLD

SAFETY

NORMAL ORtlUNG KICK ASSEMBlY PRESSURE I CHOKE FULlY OPEN I MARGIN A, 42 ~ = 4.2{~3--!.Jf CIRCUIT ANOUNESTO Pl 1 Apq I kg/cm2 I

OUA.NTilY CF BAR!lE ~Q.fREO - A , _()ju,.d HP PUMP --- Pd1 s · 4.2- wr 4.2 -1::83

Plo I kQ!c.m1. 1 ~ps {kg/cm2)

Plo• t.ps THROUGH ONE liNE THROUGH TWO LINES TOTAL WEIGHT <:F BAR!TE B Ytot x A /i7lfiJJx. 0.124 - B , 34350,.

f kg/cml) I kolcm1. J NO IF t-AUO cYCLES l0 BE u<:EO ~

::l.L+ :16 28 .15 123.-:116 INCREASE IN Ml() 'Hfi(.Ht PER CVQE t.w: ~ , - 6w ::;3Sk.9Jcm2 /C'fCLE

N .20 .. 0

11 - CALCULATION OF VOLUMES AND PUMPING TIMES 8•V<ITING RATE c = ~9_r__ ; 0.1~'1~ - c = 1_5__kglmin

--------·---· ANNULUS SPACES 'lENGTH I ANNULUS TOTAl ORILL STRING I lENGTH 'INTERNAL I TOTAl

PUMP PRESSLJIC ""titN ""~VD W2 wz .w1• t>w ,j.J35 PR2 • PR1 -t.PR x f>w ; .9Z') ____ kg"m1

1------- - VOLUME ANNULUS VOLUME INTE:RNAL 1-'EAC'ifS HIE BIT

OIAMET!:RS t m I PER METER VOllME. 00 I! ID I m l PER ME.lER VOLUME

w3 •WJ• f\,w ,1_83 ---- ·-1-llm l . I LITERS) OR lB!FT t/Jml IUTERSJ

PUM~ PRESSlft-'E wt-f;; N t..t.e w3 = 73 __ >gnm2

t«Jte5X.oc4Jg_ _-1£I _iLL __1353 .. 5,.*5~;Mji~i 41:-ACHES THE" f:'.IT PR3 = PR2- t.PR x t.w

_,oc ~ /2.•- S 3 ;~ . D cJ IV_ Calculation of pump pressure at the en:J of the control period I

s..x_.op~ :::zE5: JD.5: 3>7&2 1-t<.·.1.33 . . . UNER--•OC ! od\JL ~' I {b}__ 'i __ 331, , THROUGH ONE LINE ~-- ~- '"~' • --- kg fcm 2

+ -' OP 3.Y!L i115--4=. TI.?t 3361Z PRend: PRr + l!t.pc 1 X::!'!..!._:::--+ X--

CA$1-1G __ !!CC __ ==:========I=== THROU~t:TWOUNES -- ~ PRend=---kgfcm2

.... -•oc~ SY.2.. 0!'3 ,~,.. 3b21;: m ~1 c><m

INTERNAl VOLUME . . .. _ ...... Ydp = ~6'18L.r V_ Check that open hole is not fractured with the chosen ·s· margin 9 _o/~, DP .5__ _ _3_1_()_ Jj+ _ 12lGbO.

ANNUlUS VOlUME.. . _ ...... V a = 019~f llpc1 W• INTERNAl VOLUME CF MUD IN PlfS 10 SE WEIGHTED --·- ___ :: __9_521 f Wtrac Wfrac = --- kp/£

CHOKE liNE ...•.. 612D . . .. Weqv = Wr +10 X-

Zweak point W1

= 21'1000J THROUGH ONE LINE Weqv ::~-4- 10 x-=---ANNULUS VOLUME V a -15 5192.

TOTAL VOLUME K BE WEIGHTED ____ V tot

l CARRIED OVER ON THE RIGHT l l EXCLUDING THE R!SER I THROUGH TWO LINES Weqv =-+ 10 --- X--=---

'"'"" m •• I '" m ""'" ~ ro<>< VI_ Weighting- up the mud in the riser (before opening the BOP's)

CIRCUlAffNG VOL~E

PUMPING TIME (tT>In) ~).l/Ji~-~=-- ~j55JQD,j2g Vtot J]l(J'fL 6"93 Or ftOO Or 400 a, 4.00 - - RISER VOLUME jv,=-l]

HO OF PUMP STROKES ""-.m21.. ~ "-' _ ·15.5000· 39 ""'-:urcw.1aa;5 RCOUIAEO WEIGHT OF BARITE Br = Vr X 4.2 Wr- W 1 :::. --X 4.2 -----~ Br:: ---kg

.P!str 3.9'2. _ Rtstr 3.9~ -f/str 3.92, - 4.2-Wr 4.2-

NB' SHADED AREAS MUST ONLY BE FILLED IN FOR FLOATING RIG.

- 11


f't!MI'!N(; PRLSSl!Rf' PLOT FOR THE PFRIOIJ Dl'RIN(; WHICH

Till' WI!(;IITFil \1l'D TR:\VI'IS I·R<l'"1 SliRI·\CF '10 Till BIT

FiRST FXAMPLE

I. On the vertical pressure axis plot the value r1f f' "'. !:or the second cycle !' "~ ... etc.

2. On the horizontal pump strokes axis plot the number of strokes required to pump the mud from surface to the bit. Draw a vertical line from this point.

3. On this vertical plot the value of PR~· for the 'ec<lnd cyck !'"• .. c'tl'.

4. Join the points plotted in I and 3.

5. Select the number of pressure steps desired and calculate the number of pump strokes for each step, plot these values on the horizontal axis and draw a vertical line from each point.

6, On the· lined r:t wn in 4 read "IT the· drill pipe' prc"u re'" he 11111 i lli<tlltc'd fr<>m the· '1:1 rt nf each ,tcp and write these figures on the plot. If it is desired to minimise the pressure overbalance at the formation, the drill pipe pressure to be maintained should be the average of the pressures at the start and end of each step. lnthis case the difference between the two prc,surcs must be less than twice the safety margin (S) used in the calculations.

PR kgjcml I ! I example n°1

125

~ 110 i

107 \

104 101 98-,

~ 95 70660

90 87 11h30mi 84 ' ' 81 I

78 : I 75 ' I 73 15532

100 strokes

75 0 strokes

i 23h

50 J ' I ! ;

25 ' ' .

6832 strokj ~7 mtn

,,

0 1000 2000 3( 00 4000 5000 6000 7000 pump s~rokes

NoT!'. When using a mixed drill string this graphical method, which assumes the string to be of constant ID, may still be used providing that the mud weight increments are not too great, It is however recommended that calculations be made to check that this is indeed the case. In this example, with 910 m of 5" drill pipe at the top of the string, the pump pressure will be reduced by 6 kg/cm 2 after 2 000 strokes (7 840 litres). At this point, however, the weighted mud will only have reached a depth of I 048 m,corresponding to an increase in bottom-hole pressure of 3.7 kg/cm 2

• The net effect will therefore be a fall in bottom-hole pressure of2.3 kg/cm 2

• Since the chosen safety margin is 15 kg/cm 2 this error will be of no significance and the use of this simplifted graphical method is justiftcd.

~~~ )

- 12 :.:


Example 2: Fixed platform well. Water depth 115 m.

Well depth, Z 1 300 m 20" casing shoe at 600 m Hole diameter 17 1 I/ Mud weight 1.2

BOP's 2000 psi WP. Equivalent fracture density (leak-off test) 1.70. The drill string comprises:

1 165 m of 5" 19.5 lb/ft drill pipe 135 m of 8" 0 D x 3" ID drill collars

A control rate of 1 500 litres/min has been chosen (pump speed 30 strokesjmin at 50 litres/stroke).

The circulating pressure measured at this rate was 40 kg/cm 2 .

Upon closing in the well after the kick the stabilised wellhead pressures were:

Pd 1 = 20 kg/cm 2

Pal = 25 kg/cm 2

A safety margin of 10 kg/cm 2 will be used.

} I I {;

13

SECOND EXAMPLE


(OAILUNG FROM LAND OR FIXED SUPPORT)

WELL: 1""""'17"/.., !""'."..:••• L,..'65ml""'-." -'\.'W ··~·;~j Up<ht.Oo-n

y - . --- -,,.,. 60Dm !""•·••••""" 1.70 •,. '3Q).gJ,\ 1.40~}, lujl41'VI~·

• 1, At every bit change or crew change :

Circulate off bottom for 5 minutes 8( reduced flow rate and record pressure loss fP,,J.

I ·K- l:~~!:l·~·· c ~: r\6x 8 ~v~~s.o ··.:·eo I ~~~1 ·- • .. N~ nrok• mln~~"


• Increase in drilling rate. • Increase of flow across shale shaker. • Increase in pit level . • Gas cut mud . • lncreese in mud chloride content. • Partial or total mud losses 11/.

-+ , Pick up kelly until T.J. is 3 fr above rotary table . • Shut off mud pump - check for well flow or losses . • Notify operator and comf8ctor Tool pusher.

of • ' IF WEll IS STABLE lf WEll IS FlOWING fF WELL IS L.OOSING

• Resume circulation. • Open ihe choke line, the choke • Circulate ar reduced flow rare. • Check for mud pit level, mud

being fully open, • Check for losses. weight, and shows.

, Resume operations. • Close the bBg type . , Wait for orders.

• Slowly close the choke and record casing and drill pipe pressure for 15 minutes .

.,.., ~

I IF CASING PRESSURE REACHES P1,. l \ ff CASING PRESSURE IS LESS THAN Pm j

lohow the instructions here under : Record thia Pf"*'-''e I~. !

·Open t6e cioo~e rQ1dd lbeon~.,lm Ce!culete P!f1

as follows:

me. 'n nJ or beJow 3D Jc, ~. • n(t/W tn. 'r.Mrfld dnll ~ lW~ P_, .~O~fcnn•

• Rreo.k c;""!o.f;D,. oJ j<;r>r>0..fl~ 1 •dri thf pi'HW,.. lou •' rwJuc«i flow,.., P" .40~/orn~ •.S~gb~.no ' ,., .er· rirc. lo \;, s -.10!11§/=~ __J,_ffi,I!)e: d !0. !:e ~~~r .-J

• Wdthl tnpnwrgin

I P.,·~~ TOTAL QJ

- Op"' fldtu~t•bJ. chokl 1rtd umufiiMOIIIi-t lbl1 pump •t ,.due# flow r111, lriiu!' t;hob 10 m.mt•m• comllnt pll~l ~11 to P111 J>o not ''*• cu• Dl c11mg FliWt• 1!-1¥ fl t1111 ptiUUffiJ Ins~ P _..

l The casing pressure must never be higher than P ,..

(1} In th~ eau of total loSSf!S .fill up the IJnnufus with mud or watet tn orde1 to keep th~ lttveiiJt surf~Jce .•, /1 the well IS flowmg, close 1t m ItS mdlceted IJbove, and Wilt for mstrvctJOns

(2) P,tt ~M be dl!lter"!in~ eesily: when '!umping is startl!ld, kel!lp constant c•sing prf!lnurf f!lquafto P., + S lor • pe,od of lflw mmuus The stand p1pe pressure should be close to the P111 celculflt~ •bove


Stop tripping. Check for well flow or losses, Notify operator and contractor Tool pusher,

(' + IF THE WELL IS STABLE IF THE WELL IS FLOWING IF THf FlOW IS INCREASING. OR

·"' IF TH~ MUO GAIN RE ACMES rh' "' + Unless otherwise notified: If GAS fLOWS

Make up an inside back pressure vslv Run pipe back to bottom. In case of in drill string. lasses keep annulus full if possible.

With minimum delay, run pipe back Stop tripping. Resume circulating at reduced flow to bottom. Check mud gain. Close the bag type. rate, eventually under control ar Slowly close the chok.e. constant DP pressure (Caution : On boNom proceed as above §2. Wait for orders. some gas may enter the well bore). Bleed off if casing pressure

reaches P -·

NOTE: The Operstor Supervisor mvst fill up the Bbove shadowed sptJCtJS BS often as nectJssary,

WELL CONTROL WORK SHEET. SECOND EXAMPLE

WELL y WELL CONTROL

DATE

I _BASIC DATA

DEPTH

MEASUI18J MD( m)

VERTICAL Z(m)

SELECTED PUMP I

w liNER UTERS/STROI<E

CONTROL PUMP RATE IIN111AL MUD

Or (/I mn)

PUMP SPEED

{ Str /mini

WEIGHT

WJ (kgf!l

flOD_IJ30D _J_L!J~!-so_jl50D_I_3_G_lJ.2o __ CIRO.JLAJtt«:i PREssrnt tresEs FUR Or AND W1

tHRCWH

NORMAl ORILUHOIKICK ASSEMBLY CIRCUI! ANOLINESTO PL 1

HPPUMP ----

INITIAL

ORILl PIPE

PRESSURf

Pdt

CIRCUlATING PRESSURE LOSSES f0ROrANOW1

THROUGH CHOKE LINE ANO MANIFOLD (CHOKE FULLY OPEN I

Apq ( kg/cm2 l

SAFETY

MAROm

s lips (kg/cm2l !

Plo ,..,.m,+ =L;;: _i:a~~_l lliHUUUNUNtLINt I L~o _ I - --- --·· ----. --·- 'THROUGHTVVOUNES

40 11 _ CALCULATIDH OF VOLUMES AND PUMPING TIMES

AHHULUS '"."'" llENGI>l I ANHUlUSI tOtAl I DRilL STRING. 'lENGTH I'"'ERNALI TOTAl 1---.. - VOLUME ANNULUS VOLUME INtERNAL

OIAMEl'ERS ( m I PER METER VOLUME OD :.c 10 1 m J PER METER VOLUME

Ll!ml !UlERSI ORLBrFT li1ml IUttRS)

~~-:!:I!~ :; ~;;! .. ~s ~~s ~~ _9~n JoOOo-u···-·oc--,-·-·-- ----- ____ ocJ5_,_.3~- _-135_ _4_56. __ 615_

~~~;~=~~--6-=-0-0-_ ==_ --: --~------~-IN-tER-NAJ.-~-OlUM-E ._j. i_--__ j_Vd-p _:__L_11-~. ~fER~~~-~-: 300-· ----- - --- - :::u~::,;x:: WE~.,TEO v_a _ : ~~~i CHOKE LINE _ _

= 2.S:9K:SOt lOYAl VOLUME TO 8E WEIGHED .. _V tot 195lli ANNULUS VOLUME V a I CARR!EO OVER ON THE RIGHT )

{ EXClUO!~ THE RISER J

TotAL

PUI-!PING TI~E ( min l

SURFACE TO 8H BIT TO SURFACE C!RCU!.AllNG VOLLJ.iE.

-----··--··-- I ~ J1!tiJLLB_ ~ j951J1Q _fiG ~ :z;;q~~n= JI3 Or -'1500 Or .-1500 Or "15'00 ~j:l_ltDDJJ-2_ ~-d9.5iJJD= 39aK ~~.519zj .1' /str 50 .1' /str 50 .l'!str -1500

NO (F PUMP STROKES

NB' SHADED AREAS MUST ONLY BE FILLED IN FOR FLOATING RIG

WORK SHEET WRITER

Ill_ CALCULATION OF CONTROL PARAMETERS

REQUIRED MUD WEIGHT

PUMP PRESSUR:e el'J'OR€ SARITING MUO

Pl!l-4" PRESSURE WHEN THE WEIGHTED

MUD RE ACHES THE SIT

PUMP PRESSURE DECREASE VERSUS

INCREASING WEIGHT Of MUD

OUAN1'HY CF SARITE REWREO

w, =wpm.!'d~·S =1JO.u~ PR1 = PL1.-,Pdl • S =2,Q.JrD_ .1{)_

PRr = PL1 x .!'_!_ Wl

.<'>PR = PR 1 - PR r Wr-Wt

= ltD..x 1.;~ {Q ___ 4.8_

; /t£;3 - !1:20

A = '2 ~ = 4.21.43-1,2_0 · 4.2- wr . '-2 -AJt3

TOTAl WEIGHT <1' BARilF 8 : V tot X A :2.59/S):)._ fl.35 00 fF 1>4UO CI'ClES l0 8E u<:.EO E3J ~ !NCRf.ASE IN Ml,.() Wf!Gf-«. P8'f CYCLE /:J.W= ~ -:: J.J-3.-1 ... 20

SA~I11NO RAT€

N 3 ___ C:~Or

N- = n3s.x15DO ~

-wr ;~3

- F'RJ = Jfj__kglem2

-PR, = ...!:r2_ kg/o:m2

~ Affi =Q.9fkg!cm2/k.gd

- A ; _035_,,,/

- B :90.3_4:(2,,

- !J.w :}.7_ kglcm2 I CYCLE I

- c = lli_ kg /mm

poy.p F'I<£SSL.RE \'IHEN MlJO W2

VEAC.'-!£5 THE BIT w2 =Wt• tlW ={~7( PR2 = PRJ -.<'>PR X .6w ; ___f3_kg~<m2

PUMP PRESS- W>EN "-C WJ -1351 55 w3=W]_•l!.w =-·-'1 PR3 :PR2-.6PRxl!.w =--·--''''m'

RE•CHES "'' "'' w = . =: A.l/) PR ~ = 4 8 .lt}/""

IV_ Calculation of pump pressure at tha end of the control perind

PRend = PRr + ~pcl X :~ :: -- + X--

THROUGH ONE LINE ~--~ ~- PRend = --- kgfcm2

THROUGHTWOUNES -- _........ PRend::=---kgjcm2

V_ Check that open hole is not fractured with the chosen • S • margin

THROUGH ONE LINE

6pc1 Weqv: Wr + 10 ~oiot X~ OC:::::::: Wfr3c

WJ

Weqv :-4-10 ---- X--

THROUGH TWO liNES WeQv =-+ 10 ---- X -- = ----

Wtrac = --- kg/f.

VI_ Weighting- up the mud in the riser (before opening the BOP's)

RISER VOlUME lv,=-·-TJ REQUIRED WEIGHT OF BARfTE Br =V, X 4.2 Wr- Wl = --X 4.2 ----- _....,. Sr =---kg

4.2-W, 4.2-

-t:>

- 15 -


f>tl\11'1!'-l(i I'RESSl!l{f I'LOT !·OR THI· PERIOD Dl'JUMi WHICH

THF WFJOHTUJ \1l'IJ TRAVF.L' FR0\1 Sl'RI ACT TO THF BIT

SECO~O EXAMPLE

I. On the vertical pressure axis plot the value of P RI'

For the second cycle P Re"· etc.

2. On the horizontal pump strokes axis plot the number of strokes required to pump the mud from surface to the bif. Draw a vertical line from this point.

3. On this vertical plot the value of P Re' for the second cyck PR' ... etc.

4. Join the points plotted in I and 3.

5. Select the number of pressure steps desired and calculate the number of pump strokes for each step, plot these values on the horizontal axis and draw a vertical line from each point.

6. On till' linc.drawn in 4 read niT the drill pipe pressure· to he m;tintainc·d fmmthl' start nfcach step and write these figures on the plot. If it is desired to minimise the pressure overbalance at the formation. the drill pipe pressure to be maintained should be the average of the pressures at the start and end of each step. In this case the diiTcrence between the two pressures must be less than twice the safety margin· (S) used in the calculations. •

PR k9jcm4

example n°2

70 69

I-+-- 66 H-- 64 5200 r-. 62

63! 2hso 60 ;--59

51 -H-- 56 1040b - 55!6hsl 50 --+-- 51

49 ' : '156QO ' : 4~ 8h36 : '

strokes

strokes

strokes

I

' ' 40 '

I ;,

' ' ' ' ' ' ' ' ' ' ' ' '

50 : 100 150 I 200 228 stroke 0 80 160 pump strokes

Steps drawn at the average of the pressures at the start and end of each step.

ANNEXE IV

WELL VOLUMES FORM

I PHASE: DEPTH :

Volume mud 1n Circulation:

Volume mud rn reserve:

Volume Casing ( int')

Volume open hole

I VOLUME WELL EMPTY

Volumes

Drill Collars

Vol ext'

Vol int.' Vol. metal

Drill Collars

Vol ext.' Vol. int.'

Vol. metal

Drill P1oe Vol. ext' Vol. int'

Vol metal

Dri!l Pioe

Vol ext r

Vol mt r

Vol metal

Drd I P112e Vol ext r

Vol int' Vol met a!

( bbls/ft )(I /m)

(bbls/ft )( 1/m) (bbls/ft.) ( 1/m)

D1splacement drill string (Vol ext.')

Volume lntenor

Volume metal

VOLUME I

VOLUME

ANNULUS

INTERIOR

VOLUME MUD IN WELL

I Author • N. CA MP BE L L

I Droft,ng J.M.B

metres

d:

d

DATE,

=

=

ANNEXE 4

I

Vol. Ext'. Vol. lnt'. Vol. Metal

(m)( ft)

(m )(ft) (m )(ft)

I Dot• SEPTEMBER, 1978 I o ... g No 16285

j_Report No : lsai• Pion~ '! I

' I I

ANNEXE V

MUD CONTROL FORM

ANNEXE !i

MUD CONTROL FORM DATE: I TIME WEIGHT VISCOSITY FILTRATE SAND TANK LEVELS LOSSES GAINS ADDED r1UD PRODUCTS AND COMMENTS l (MARSH) (CC/30') CONTENT TANK 1 TANK 2 TANK 3 SURFACE OR SUBSUF

I

' I

DRILLER :

DERRICKMAN:

PUMP NO LINER SPM FLOW RATE DESAND (HRS) DESILT(HRS)

I I

I /

I I I ' ! ! I I

. I

ANNEXE VI

KILLING A WELL 11 DRILLERS METHOD 11

Where:

A B B R E V I A T I 0 N S

SIDPP = Shut in drill pipe pressure SICP = Shut in casing pressure (annulus) di = Initial mud weight (SG or PPG) dr = Mud weight required (SG or PPG) Z = Depth (metres or feet) Q = Flow rate during drilling Qr = Reduced flow rate (normally half of drilling flow rate) CCP = Pressure loss at reduced flow rate (constant Circulating Pressure)

M.Ad.P = Maximum admissible pressure under a closed BOP in respect to fracturing the formation at last casing shoe depth.

M.W.P = Maximum well pressure allowable under a closed BOP in relation to BOP pressure rating or casing burst pressure. May also be M.Ad.P.

SG = Mud weight in Specific Gravity PPG 2 = Mud weight in Pounds per Gallon (US)

Kg/cm = Kilograms per square centimeter. 1/m = Litres per metre.

bbls/ft= Barrels per foot Vint = Volume interior Van = Volume annulus Vtot = Volume total in circulation CDPP = SIDPP + CCP + S = Pressure loss at reduced flow rate plus shut

in drill pipe pressure plus pressure safety factor= Pressure required on stand pipe to begin2killing the well.

= Pressure s2fety factor. Usually 14 Kg/cm (200 psi) or 5 Kg/cm (70 psi) per 1000 metres (3300 feet) of depth.

s CDPPr = Surface pressure loss after addition of barytes when such

PR A

B N d

c de qv 4.2

new mud is at bit. = Pressure reduction by each point mud is raised. = Quantity of barytes required to raise initial mud weight

to required mud weight = Total volume of barytes required. =Number of cycles of circulation chosed to kill the well. - Number of points mud weight is raised each cycle of circulation. = Rate at which barytes is added to the mud system. = Mud weight to pressure at given depth. = Density of barytes in SG.

- 1 -ANNEXE 6

KILLING A f'lELL BY USING THE 11 DRILLERS METHOD 11 AFTER SHUT IN PRESSURES

HAVE BEEN OBTAINED 1) EVACUATION OF FLUID AND/OR GAS THAT HAS ENTERED A WELL (SEE NOTE BELOW)

1.1) Open the choke manifold 1.2) Recommence circulation at half the normal flow rate

as that used in drilling and keep this flow rate constant (see Drillers Instructions Chart for:Qr).

1.3) Simultaneously operate the adjustable choke to maintain a constant back pressure on the annulus equal to the SICP plus a safety factor of 200 psi (14 kg/cm2)

1.4) When the annulus pressure is stabilised note the pressure on the drill pipe and maintain at a constant pressure by using the adjustable choke until one cycle of circulation is completed and the intruding fluid and/or gas is evacuated from the well.

2) CALCULATE THE MUD WEIGHT REQUIRED TO CONTROL A WELL 2.1) Pressure on drill pipe with well shut in = SIDPP in

kg/cm2

Safety factor: Depth of well:

200 psi (14kg/cm2) Z in meters

Weight of mud in circulation: Initial mud wieght: di Weight of mud required: dr Therefore: dr = di + 10 SIDPP + 14 in Specific Gravity

z 2.2) Fabricate a volume of mud equal to the volume of mud in

Circulation at the mud weight calculated at dr.

3) KILLING THE WELL 3.1) Pump the mud at mud weight dr, maintaining a constant

. . 2 pressure on the annulus equal to SIDPP + 14kg/cm by using the adjustable choke.

3.2) When the volume of the interior of the drill pipe has been pumped note the pressure on the drill pipe and maintain at a constant pressure during the rest of the circulation and until the well has been killed .

. . . . /2

- 2 -

NOTE: It is important to evacuate the fluid and/or gas that has entered the well before adding barytes to the mud.

4) PRESSURES Pore pressure can be calculated as:

Ppore = z x di + SIDPP in kg/cm2 10

or Ppore = Z x di 0,052 = SIDPP (Psi) in psi Mud weight required can be calculated as: dr = di + 10 SIDPP = 14

z in Specific Gravity

or dr = di + SIDPP + 200 in P.P.G. 0,052 z

Circulation pressure required to kill a well

CDPP = CCP + SIDPP + S Quantity of Barytes reouired to kill a well

A = 4,2 dr - di 4,2 - dr

or A = 4,2 dr - di 4,2 - dr

Total Barytes required

B = Vtot x A in

in kilograms per litre

x 350 in lbs per bbl.

kilograms if Vtot is in 1 i tres or B = Vtot x A in pounds if Vtot is in bbls.

Where: Ppore = Pore pressure Z = Depth in meters SIDPP = Shut in drill pipe pressure di = Initial mud weight dr = Required mud weight CDPP = Circulation pressure required CCP = Pressure loss at reduced flow rate S = Safety factor, usually 200 psi (14 kg/cm2) A = Quantity of Barytes required Kg/l or lbs/bbl B = Total quantity of Barytes required, kg or lbs Vtot = Total volume of mud in circulation

NOTE 1 kg/cm2 = 14,2233 psi 1psi = 0,0703 kg/cm2.

ANNEXE VII

12 11 3000 PSI WELLHEAD

Australian Aquitaine Petroleum Pty. Ltd.

RECOMMENDED WELLHEAD ARRANGEMENT

12"3000 FOR DRILLING

Hydril GK

12" 3000

Pipe rams

12l .. HOLE 4

Flow nipple 8"or10"

Shoffer /Comeron Double

12" 3000

Blind rams

Kill line 2" 3000 Mud Cross 4 "or 3" 3000

Choke ltne

2" plug

·.-._·.

Spocer Spool

2" valve

Line to rig floor (Drillers position) wtth Martin Decker gouge or similar to monitor annulus pressure if well is shut in.

Casing spool 13~" x 9i" 3000 1----___;-4

13 3" c . 8 ostng

f---N_. _c_A_M_P_e E_L_t4

_oa_,._. _s E_P_r_l_9_7 a--i-0-wg::.__N_o_., -' 6_2_8 -6----1 ANN E X E

Drafting• S. W. S. R•port No.' Soi• Pion • :::s:z::II ..__ __________ _.;~___:. ____ ...J......:.:;...----.. ___ ___l....:.::..;,.:.....;,.;,:;.;_ ___ ...J__...:....::.__."

ANNEXE VIII

12 11 3000/10" 3000 WELLHEAD

A us t ra!Jan Aquitaine Petroleum Pt v L td


12" 3000 I 10"3000 FOR DRILLING 8 .!_u HOLE 2

Hydri I 12" 3000

Pipe rams

F I o w n i p p I e 8 " or 1 0 "

NOTE : Adapter flange or mud cross mo y be used as cross- over rrom 10" 3000 or 12" 3000

Shoffer I Cameron Double

12" 3000

B !in d rams

12"3000

i Kill l1ne 2" 3000 Mud Cross 4" or 3" ::

3000 choke :: Line to r1g floor (Drillers position) or above cellar level wi'th Martin Decker gauge or similar

2" pi ug

C 9 s.. 7";sl" astng spool 8 x 2

10" 3000

Conductor 131." 8

I ine 1 1

11 10" 3000 11

~ to monitor annulus pressure if well is shut in.

9 ~" c 8 asing

Author N. CAMPBElL Doto SE PT 19 7 8 Owg No. 16 2 8 7 ANNEXE ~------------~---------------~--------------~

Drothng S. W S. Report No · Bost Pion~

ANNEXE IX

10" 5000 PSI WELLHEAD

Australian Aquitaine Petroleum Pty. Ltd.


10" 5000 FOR DRILLING al." 2 HOLE

2" plug

H yd r i I

10 "

GK

5 000

Pipe rams

Ring gasket R54

S ha ffer I Cameron Double

~IT><l1 2"5000

10" 5000

Blind rams

Mud Cross

10" 5000

Spool 7"

10" 5000 X J2" 3000

R 54

R 54

1 "

1 Line to rig floor (Drillers position) with Martin Decker gauge or

• similar to monitor annulus 1 pressure if well is shut· in.

0><1J G..-=--2 --

2 "5000

R 57 ,--.1.----4.....1--.

R 57 .---.1..----I-J........, Testing flange 12" 3000

2" plug

3 •" 13 8" •casing

5 ' •' ' ' 9-" casing

8 ' '

hanger

J31._" X 9:?_" 3000 8 8

Avtfto" 'N'CAMPBELL·. Dote• SEPT. 1978 D wg No., 1 6 2 8 8

Drafting• S.W.S. Report No.: 8ai• Pion •

ANNEXE X

SAFETY CONTROL FORM

- 1 -

ANNEXE 10

SAFETY CONTROL FORM

To be completed each week and at after each change in the BOP or H.P. System.

A. DISPLAYS

Are the following documents displayed at indicated places:

l. 1•/ell drill inq program chart (except for tight hole).

2. BOP's and choke manifold drawings.

3. Driller's orocedures (model F 8 bis) filled in by Operator's Supervisor.

4. Mud system drawings.

5. Pump liners, maximum nressure, volume per stroke.

6. ~~ud vo 1 umes and inventory.

6.1 Volume and weight of active mud. 6.2 Volume and weight of reserve mud. 6.3 Barite inventory (or Calcium Carbonate). 6.4 Bentonite inventory. 6.5 Lost circulation materials inventory. 6.6 Cement inventory.

7. Mud oit level control instructions.

8. Alert instructions for the on-site geologist.

9. Addresses and telephone numbers of Operator's and Contractor's Suoervi sors.

B. CONTROL EQUIPMENT

1. Can qas seoarated from the mud be safely discharged and flared?

2. Is the flare located outside the restricted area?

3. Are the flare stack and flare line well anchored?

4. Has the degasser been operated in the last two weeks or at specified intervals?

- 2 -

5. On each trip or every two days, are the ram-type BOP's operated with reduced flow rate established through chokes?

6. Is the annular preventer operated no more than once a week?

7. Are both main and remote BOP hydraulic control systems in workinq condition?

8. Is the BOP emergency closing system in working condition?

9. If this system is hand operated, are the number of turns clearly labeled on the hand wheels?

10. Are valves on SOP's, choke manifold and fittings greased and operated once a week?

11. Is the kelly-cock orerated and greased on each trip?

12. Are BOP bolted flanges checked every month?

13. Are BOP's correctly centered and anchored (no vibration)?

14. Are BOP's, fittings and choke manifold tested under pressure after work on this equipment, after a casing job, before entering a reservoir or periodically (every month unless otherwise specified)?

15. Are extra parts for chokes available?

16. Does the accumulator capacity oermit one closinq and one opening of the entire BOP components?

17. Can all preventers be closed in less than 20 seconds?

18. Can accumulato~s be recharged in less than 10 minutes?

19. Can the annular preventer closing pressure be adjusted?

20. Are there devices to ignite the flare (flare gun)?

21. Are explosimeters available to check cellar and sub-structure atmosphere?

22. On the rig floor, are two inside BOP's available and are they properly maintained, and provided with the right subs to be stabbed on drill pipes and drill collars?

c.

- 3 -

23. Is there one properly maintained high oressure circulating head with rioht subs?

24. Are there five (5) 5~000 psi WP (or more) chiksan units with fittings to be nippled up to the stand pipe~ the circulating head or the choke manifold?

25. Is there a device to cut the loggin9 cable?

26. Is there a pair of bronze sledge hammers?

DETECTION EQUIPMENT

1. Is the possum belly tank nippled up and in use?

2. Is the mud oit level recorder working?

3. Is the total-gas detector properly nippled up?

4. Is the drilling rate recorder working?

5. Is the extra detection equipment provided for in the drilling and mud-logging contracts in working condition?

D. PERSONNEL TRAININ~

1. In order to check competence and skill of mud-logging crews, mud engineers and drilling crews~ are alert drills held once a week, times and recorded on the daily report?

If not held weekly~ indicate frequency.

E. TRANSPORTATION

Means of transoortation and time necessary to supply the following items to the rig:

1. H.P. pumping unit.

2. Mud products.

3. Cement.

tlf aquitaine - 4 -

I F12BIS /6-791

SAFETY CONTROL SHEET FOR BLOW OUT PREVENTION ON LAND RIG

PERIOD: MADE UP BY : WELL :

TO COUNTRY

DISPLAY 8 CONTROL EQUIPMENT OF DISPLAY

YES NO

DOG GEOLOGY MUD HOUSE LAB. 7 13 20

YES NO YES NO YES NO 8 14 21

3 9 15 22

4 10 16 23

5 11 17 24

6 12 18 25

DETECTION EQUIPMENT 19 26

YES NO CODES YES NO D PERSONNEL TRAINING

4 CODE YES NO

2 5

3 FREQUENCY:

E TRANSPORT DAY

MEANS DELAY

2

3

_ SUGGESTIONS

DATE AND SIGNATURE OPERATOR'S SUPERVISOR

.ANNEXE XI

GENERAL S.AFETY RULES

1 ' J

1. SMOKING

- 1 -GENERAL SAFETY RULES ANNEXE 11

AFTER SPUDDING IN, SMOKING WILL NOT BE PERMITTED WITHIN A RADIUS OF lOO FEET OF THE I~ELLHEAD. 910KING ON RIG FLOOR, ~~UD T.A.NKS, AROUND BOP AND MUD PU~1PS \~ILL NOT BE PERMITTED

2. l~ELDING

PERMISSION FOR WELDING AND OXY-ACETYLENE CUTTING WITHIN A RADIUS OF lOO FEET OF THE WELLHEAD MUST BE OBTAINED FROM THE AQUITAINE REPRESENTATIVE.

3. EQUIPMENT

SAFETY GUARDS WHERE PROVIDED, MUST BE INSTALLED ON MOVING MACHINERY.

4. ENGINES

THE MAIN RIG ENGINES MUST BE EOUIPED WITH SPARK ARRESTORS AND HAVE AUTOMATIC SHUT DOWN.

5. PERSONNEL

SAFETY HATS AND SAFETY BOOTS MUST BE WORN AT ALL TIMES. NO UNAUTHORISED PERSONNEL \~ILL BE PER~1ITTED ON THE \~ELL SITE WITHOUT APPROVAL FROM THE AQUITAINE REPRESENTATIVE AT THE WELL SITE.

Encl. Hydrill Testing and Rotating/stripping pressures

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HYDRIL BLOW-OUT-PREVENTERS TESTING PRESSURES

(from Hydril information)

The indicated pressures are average required pressures and are listed only as a guide to the proper setting of the regulator valve. The actual pressure required to make a seal will vary slightly for each individual packing unit. The pipe sizes listed are the optimum causing the least strain on the packing unit.

WHEN ROTATING OR STRIPPING THROUGH A HYDRIL BOP:-

Use only the minimum closing pressure required to hold well pressure. When stripping, a small amount of leakage should occur around the drill pipe for lubrication purposes. The small amount of leakage also assures the operator that the light holding pressure is being applied. Leakage is especially important when rotating for the purpose of removing heat produced by friction of pipe rotation on packing unit.

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TESTING llYDlUL EOP' s

Size Recommended size Recommended Recommended Blowout pipe on which closing pressure closing pressure Preventer to close for listed pipe on open hole

)

1rsr..:6-2000 2.7/8" 450 1000

GK-6-3000 2.7/8" 450 1000

GK-6-5000 2.7/8" 450 1000·

GK-7 .1/16-:10,000 2.7/8" 750 1150

i HSP-8-2000 2.7/8" 550 1050

GK-8-3000 3.1/2" 450 1050

GK-8-5000 3.1/2" 550 1150

rrc,..:.9.:..1o, ooo i )

3.1/2" 570 1150

~~P-10-~000 3.1/211 550 1150 i .

3.1/2" 550 1150 GK-10-3000

GK-10-5000 3.1/2" 550 1150

GK-11-10,000 3.1/211 600 1150

i

I GK-12-3000 .4.1/2". 550 1150

GK-13.5/8-5000 4.1/211 650 1150

GK-13.5/8~10,000 4.1/2 11 550 1150

I GK-16-2000 I 4.1/2 11 500 1150

_GK-16-300 4.1/2" 550 1150 i l u.tZ-16. 3/4-5000 •' 4.1/2" 600 1150

I GK-18-2000 4.1/2 11 600 1100 1

~fSP-20-2000 4.1/211 550 1100

i ;

NT Minerals and Energy · •A• Northern Territory Government ) lnfoCentre NT Minerals and Energy...

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Transcript of NT Minerals and Energy · •A• Northern Territory Government ) lnfoCentre NT Minerals and Energy...