Longwall AFC changing - innovation

Armoured Face Conveyor (AFC) pans changing in a working Longwall face

using Monorail system-AN INNOVATIVE APPROACH

SINGARENI

COLLIERIES

COMPANY

LIMITED

ON THE OCCASION

OF OF

ENGINEER’S DAY

PRESENTATION OUTLINE

• About GDK.10A Incline

• Details of Panel No.7

• Reasons for replacement of AFC

• Conventional methods• Conventional methods

• Monorail transport system

• Sequence of Operations

• Safety & Advantages

• Conclusion

SALIENT FEATURES OF GDK 10A INCLINE

� Mine started on : 16-06-1985

� Introduction of Longwall : FEB, 1994

� No. of workable seams : 2 (No.1 & 2)

� Present working seam : No.1 Seam� Present working seam : No.1 Seam

� No of LW panels completed: 8

� Total production : 54 LT

� Balance reserves : 35.82 LT

� Balance life : 3.5 Years

� Project cost : Rs. 116.53 Crores

PRODUCTION PROFILE OF GDK-10A

(Coal production in LT)

Section 2003-04 (Achiev.)

2004-05 (Achiev.)

2005-06 (Achiev.)

2006-07 (Target)

HS 0.09 0.01 0 0

MM LW 4.00 3.48 4.16 5.00MM LW 4.00 3.48 4.16 5.00

RH 0.32 0.29 0.32 0.40

SDL 0.69 0.93 0.92 0.96

MM TOT. 5.01 4.70 5.40 6.36

TOTAL 5.12 4.71 5.40 6.36

Plan of No.1 Seam No.1 Seam

GDK 10A INC.

How a Longwall face looks like…

PANEL NO 7

Face Length : 116 m

Panel Length : 940 m

No of chock supports : 80 Nos

Shearer : 2 X 375 KW

AFC : 2 X 150 KW

BSL : 1 X 150 KWBSL : 1 X 150 KW

Lump Breaker : 1 X 90 KW

This panel was planned with uphill AFC transport toeliminate water problem. After a retreat of about 400 mit was decided to change the AFC pans as the conditionof AFC was severely deteriorated. Monorail system wasused for transport of AFC pans along the face.

Longwall Panel No.7

MAIN GATE (46L)

400m

TAIL GATE (49L) FACE STOP LINE

Uphill Transport is planned in this Panel

GOAF

REASONS FOR REPLACEMENT OF AFC PANS

� The quality of AFC pans was very poor.

� AFC components were supplied by 3 differentsuppliers.

� Percentage of AFC breakdowns was about22.5% of available working time and22.5% of available working time andresulted in loss of output of 20,000 Tons permonth.

� Slow face retreat caused strata controlproblems during periodical weightings.

Taking into consideration of the time loss,production loss and safety aspects, it wasdecided to replace the total AFC with new pans.

CONVENTIONAL METHODS AVAILABLE FOR AFC PANS CHANGING

The sequence of operations include:

- Extra cut in front of AFC

- Meshing of roof and face bolting

- Laying of track in front of AFC andinstallation of compact hauler

1

installation of compact hauler

- Dismantling of old pans, loading andtransport out bye and simultaneouslytransporting new pans to face andassembling.

This method requires extra time for giving extracut and meshing. Dismantling and removing ofold pans and assembling new pans may be donefrom any end.


1

This method does not require an extra cut but thesequence of operation include:

• Dismantling of Tail gate (TG) drive

• Installation of compact hauler

• Dismantling of old pans, loading and transport out byestarting from the Top gate end

Track extension in the place where old pans are


2

• Track extension in the place where old pans areremoved

• Removing all the old pans one after the other up to theBottom gate end and continuing track extension,

• Transport of new pans and unloading,

• Removing the track and assembling new pans startingfrom the Bottom gate end.

• Assembling TG drive.

In this method the old AFC will have to be completelyremoved before installing the new pans.

CONVENTIONAL

2


WHY MONO RAIL TRANSPORT SYSTEM IS SELECTED

� The conventional systems take around 15to 20 days time for changing total AFC.

� In conventional systems a clear space isrequired for laying curved track in Tail gatejunction and also for accommodating Taildrive.

� The roof condition in Tail gate and alsoalong the face was not good.

BAR CHART OF ACTIVITIES

S.NO. ACTIVITY DAY 1 DAY 2 DAY 3 DAY 4 DAY 5 DAY 6 DAY 7 DAY 8

1 FACE CLEANING & BAMBOO BOLTING

� Total changing of AFC pans was completedin 8 days.

1 FACE CLEANING & BAMBOO BOLTING

2 MONORAIL FIXING

3 OLD PANS REMOVING, TRANSPORT TO

TG AND LOADING

4 NEW PANS TRANSPORT TO TG, LIFTING

WITH MONO RAIL, TRANSPORT AND UN

LOADING IN FACE

5 PANS ASSEMBLING,TOP CHAIN

CONNECTION AND MONORAIL REMOVAL

8 TRIAL RUN

DESCRIPTION OF MONORAIL SYSTEM

Monorail transport system consists of thefollowing components:

1) Monorail

2) Bogie2) Bogie

3) Lifting arrangements

4) Winch or Hauler (Optional where the gradient is more and require more effort for pulling)

Plan showing the Total Face layout

with Monorail system

PANEL NO.7PANEL NO.7PANEL NO.7PANEL NO.7

MONO RAIL

• The monorails are made ofrolled section of ISMB150mm x75mm of 6 m length.

• They are anchored to the chockcanopies by chain links andcanopies by chain links andclamps.

• In gate roadway the monorail isanchored by a clamp to the eyebolt grouted in the roof.

• Monorail joints are clamped atthe top and welded at thebottom for smooth travel.

BOGIE

•Monorail Bogie was made of 15mmMS plates and rollers fitted withbearings.

•It has provision for fixing a ram orchain block for lifting purpose.

•Bogie moves on monorail.

BOGIE

PARTS OF MONO RAIL BOGIE

240 mm

BEARINGS

LIFTING HYDRAULIC CYLINDER

MONO RAIL BOGIE

3" X 6" RS JOIST

15mm MS PLATES

BOLT AND NUT

620 mm

3"X 6" RS JOIST

AND M25 BOLT

15 mm MS PLATE

M36X160 STRUD

BEARING

40mm0

100 mm

LIFTING HYDRAULIC CYLINDER

0

255 mm

040 mm

100 mm

120 mm

FRONT VIEW SIDE VIEW

LIFTING ARRANGEMENT

• Hydraulic ram or chain pulley block can beused for lifting purpose.

• It is fitted to the monorail bogie. Because of• It is fitted to the monorail bogie. Because ofheight constraint hydraulic ram is used.

• After lifting the AFC pans with the help ofram pressure, it is retained by closing On-Offvalves fitted to the connecting hoses.

WINCH (or) HAULER

• For pulling effort a winch or hauler is used.

• If the winch or hauler is erected in bottomgate road instead of top gate, rope has to bepassed through diversion pulley.passed through diversion pulley.

• 12mm or 16mm flexible rope is used withthe winch.

• Signaling arrangement provided all along theface to ensure safety of operation.

Transport of pans by pulling or pushing of

the bogie

Arrangement of diversion pullies

FACE CONDITION BEFORE CHANGING AFC

• There were total 70 pans in the face fromC7 to C76, excluding the pans of MG and TGdrives.

• Shearer was parked between C7 and C16.

Dismantling of old pans was started from TG• Dismantling of old pans was started from TGend, Simultaneously monorail was laid up toC17.

• After changing of pans up to C17, shearerwas taken down to C17-C26 and pansrequired for the other side of shearer wereunloaded at C27 and pulled through the gapbetween shearer and face.

• AFC pans were transported from surface toLongwall face through tail gate and kept underthe monorail.

• Pans were lifted with monorail bogie in TG.

AFC PANS CHANGING – SEQUENCE OF OPERATIONS

• Pans were lifted with monorail bogie in TG.

• Hauler rope was attached to the bogie and it waspulled. Bogie moved on the monorail from tailgate lifting point up to the unloading point in theface.

• Stop blocks were used to prevent run away ofbogie.

Monorail negotiating a curve in tail gate junction

Arrangement of monorail at face

curve

• New pan was unloaded at the site with thehelp of the same hydraulic cylinder.

• Old pans were lifted in the face, transportedwith the same bogie to tail gate and


with the same bogie to tail gate andunloaded in to the half tub.

• A loop line was given in tail gate forshunting the old pans loaded half tubs fromwhere they were transported to surface.

• Total 70 old pans were replaced with new pansstarting from tail gate end.

• Replacement of one pan took about 45 to 60minutes.


minutes.

• An average of 15 pans were changed per day.

• After completion of AFC pans assembling, topchain spreading and jointing was done and AFCtrial run taken. Mean while monorails weredismantled and normal production resumed.

SAFETY FEATURES

� Depending upon the load to be handled theanchoring, steel sections, bogies, lifting device andchains were designed, taking maximum factor ofsafety into consideration.

� Persons were not directly coming into contact with� Persons were not directly coming into contact withthe heavy materials while transportation.

� Anchoring of the monorails was at every 1.5 minterval increased the load bearing capacity.

� Sprags were applied immediately behind the bogietravel at the interval of 1.5 m to prevent therunning back towards down hill.

APPLICATIONS

� Monorail system of transport can be widely used inunderground mining works for loading, unloading,shifting of heavy machineries and equipment.

� Monorail system can be used at Longwall salvageand installation operations.and installation operations.

� Winder house and haulage installations forreplacing of gearbox, motor, drum, shaft etc.

� Pumping stations.

� Shaft insets for loading and unloading of materialsinto the cage.

ADVANTAGES

• More safety.

• Less manpower.

• Easy to handle.

• Faster system of transport / replacement of worn-out items.

• The monorail system can be fabricated and• The monorail system can be fabricated andinstalled at mine level with the help of workshop.

• The cost is very less when compared to othersystems.

• The workmen are more interested to use thissystem as less physical exertion is involved forhandling / transport of the material.

• The system can be further improvised byproviding motorised lifting device / bogie.

CONCLUSION

• The monorail system was found to be moreuseful for changing the AFC in a workingLongwall panel.

• Total AFC pans were changed within 8 daysusing 1200 man shifts against the normalusing 1200 man shifts against the normaltime of 20 days using 3000 man shifts, thussaving about 1800 man shifts and 12 daysproduction costing around Rs. 2 Crores.

• This system is more safe, easy to fabricate,install and operate.

THANK THANK THANK YOU

THANK YOU

Longwall AFC changing - innovation

Technology

Transcript of Longwall AFC changing - innovation