• Steam Trapping – Latest Trends

Importance of Steam Trapping

• Trap the Live steam and Remove Condensate Efficiently.

• It’s a crucial link between the steam and Condensate Loop

• What Considerations for selection of Traps -• Mainly – Application & Sizing • Air Venting

• Condensate Removal - at varied conditions

• Performance & Reliability – perform with minimum attention

Conventional vs Latest Trends

• Application - Header Drip legs

CONVENTIONAL TRAP INSTALLATION

1000 traps =5000 valves =5000 possiblestem and body

gasket leaks

PROBLEMS WITH TRADITIONAL TRAPPING

v Length of assembly - 600mmv Weight - 13.5kgv No of connections / welds - 21v No of components - 23v Materials of construction are variable with the

chance of corrosionv Time to install - 4 hours +v Valve leakage - 5 stems to leakv Heat emission - High

HIDDEN COSTS - PIPEWORK

v Each component must be specified/selectedv Each component must be purchased and specs

confirmedv Each component must be accounted for

v Each component may have a material certificatev Pipework must be designed and drawn

v This design must be approved

HIDDEN COSTS – WELDING

v Non Destructive Examination:-– Dye penetrant– Magnetic particle– Ultrasound– Radiography

v Sites think welders’ time is freev Welding could be sub-contracted

v Hot work permit - delay

Compact Trapping Station

• Overall length reduced to 160mm

• Only 1 component to install / select

• Only 2 welds to install in line

• All stainless steel construction for long life

• Time to install - less than 45 mins

• Weight reduced to only 4 kg

• Zero valve leakage - due to piston valve technology

• Heat emission is low - less surface area

TD Traps with swivel connectionCompact Trapping Stations for Main Line Drains

TRAP BYPASS VALVE

TRAP VENT VALVE

TRAP TEST VALVE

STEAM INLET

CONDENSATE

Universal Thermodynamic Trap

( UTD3 )

Pipeline Connector (PC01N) ----having Inlet & outlet isolationpiston valve ((integratedin singlestem-piston)

COMPARISON:PC1+UTD / CONVENTIONAL

Estimated weight : 13 kg 4.0 kg

Assembly Parts & Labor5 ea. 600# rated globe or gate valv es 1 ea. Line strainer8 ea. Sch 80 nipples 16 ea 1/2’’ welds2 ealine “tee” 1 ea. Steam trap1 ea. elbow

CONVENTIONAL PC1+UTD

720mm 160 mm

245mm

Conventional vs Latest Trend

• Application – Steam Tracing

COMPARISON: COMPACT / CONVENTIONALFOR STEAM TRAP ASSEMBLY FOR LP TRACING LINE

Estimated weight : 13 kg 4.0 kg

CONVENTIONAL PC 35 +UBP21CV

720mm150 mm

Ø

200mm

Steam Condensate

Inlet

Outlet

Bypass Valve

Thermostatic Trap with un built check valve

Pipeline connector having trap upstream isolation valve

Model: PC35 with UBP21CV

Model: PC35 with UBP21CV

Glandless Piston valve for upstream isolation valve

Steam from the tracing line

Condensate from the trap Universal Balanced Pressure

Thermostatic Trap with in built check valve (UBP21CV)

Glandless Piston valve for Bypass

Pipeline connector (PC35)

Stalling Conditions on Plate Heat Exchangers and Air Heater Batteries.

• Conventional – Ball Float Steam Traps

• Latest – Automatic Pump Traps

Heat Exchanger

P2

P1

Product Temperature Input

Stall conditions

Heat Exchanger

Stall conditions

P2

P1

Product Temperature Input

Exchanger waterlogging

Exchanger waterlogging causes:

• Reduced heat output

• Control valve hunting

• Product quality problems

• Unreliable process times due to temperature fluctuations.

• Corrosion

• Waterhammer

• Distortion and damage

• Freezing and thermal stresses of plant and piping.

• Unacceptable downtimes for maintenance and repairs.

Plate heat exchanger oversizing causes stall to occur at higher load conditions

• Waterhammer

• Escaping steam

• Frequent repairs

• Costly replacement

Air handling units: maintenance problems

‘Open University’ Project Slide 21

How the APT operates (1)

Condensate enters the body through the inlet swing check valve causing the float to rise.

The float is connected to the trap mechanism via a multi-link pivot.

If the upstream system pressure Ps is sufficient to overcome the back pressure Pb, the build up of condensate will be discharged through the opening two stage trap mechanism.

In this way, the float will automatically modulate according to the rate of condensate entering the APT, controlling the rate of opening and closure of the trap.

‘Open University’ Project Slide 22

How the APT operates (2)

With some temperature controlled equipment, it is possible for the system pressure (Ps) to be lower than the back pressure at (Pb).

If this occurs a standard trap will ‘stall’, allowing the condensate to flood the equipment being drained.

‘Open University’ Project Slide 23

How the APT operates (3)

However, with the APT, the condensate simply fills the main chamber - lifting the float until the changeover linkage is engaged, opening the motive inlet and closing the exhaust valve.

‘Open University’ Project Slide 24

How the APT operates (4)

The snap action mechanism ensures a rapid change from the trapping mode to the active pumping mode.

With the motive inlet valve open, the pressure in the APT increases above the total back pressure and the condensate is forced out through the trap seat into the plant’s return system.

‘Open University’ Project Slide 25

How the APT operates (5)

As the condensate level falls within the main chamber, the float re-engages the change over linkage, causing the motive inlet to close and the exhaust valve to open.

‘Open University’ Project Slide 26

How the APT operates (6)

As the pressure inside the APT equalises with the condensate inlet pressure through the open exhaust valve, condensate re-enters via the inlet swing check valve.

At the same time the outlet ball check valve ensures no condensate can drain back into the main chamber and the trapping or pumping cycle begins again.

Spirax condensate removal solutions-Automatic Pumping Traps

Condensate removal from multi-heater applications using the Automatic Pump Traps

Condensate removal from plate heat exchangers Automatic Pump Traps Trap Monitoring

• Why do we need to monitor Steam Traps?

Performance of Traps -- FM Energy Audit Findings

Current Scenario(FM Audit Findings and Data Base)• 85000 Steam Traps in Oil & Petro Chemical Industries

– At least 30 % need attention for s team loss !

• 1,00,000 Traps in Process Industries – At least 30% need attention for steam loss !

• As a very conservative figure, even assuming 20% as faulty traps, the steam loss at 6 bar pressure wastes @ 40 kg/hr / Trap ; would be1480000 kg/hr

• If we consider plants operating at an average of 12 hrs /day, 300 days a year that would mean overall steam loss of 5328000 Tons per year

Reasons for trap failure – our findings from customer complaints logged in the system

damaged seat16% air lock

6%

wrong alignment

6%SLR more than

crack open25%

strainer choked9%

normal wear and tear

5 %

float puncture12%

wrong application

21%

Steam trap failure

All types of steam traps failures can be classified into two broad categories

• Open condition (Steam Leak)

• Closed condition (Water Log)

Steam trap failure—open conditionIn this condition the trap leaks steam

• Leaks can be detected visually for traps discharging to atmosphere.

• Difficult to differentiate the flash steam from live steam.

• Impossible to detect in traps discharging to closed circuit.

Red light

Sensorexposed

R16CAutomatic

Tr apMonito r

Failed Open -causes

• SLR unit remains more than crack open • Trap is not properly aligned that results in

leakage • Seat is damaged .

Failed Open - Repercussions

• Wasted Steam = Wasted Fuel = Wasted Money• Steam in condensate line • Pressurisation of condensate line• Excessive back pressures acting on other traps

(group trapping)• Failure to maintain constant pressure /

temperature• Reduced pressure differential across good traps• Unsightly escaping steam• Steam starvation if supply is tight.

Steam trap failure –Failed Closed

• Leaks can’t be detected visually.

• Process temp. is not attained which gives the hint of a trap failure.

• Bypass is opened resulting in steam and condensate loss (process)

• Wet steam in process.

Obstruction

Orange Light

Sensordetects

loweredtemperature

Closed failure-causes

• Choking of strainers• Mechanical failure (Float puncture in ball float

traps)• Air lock (due to absence of TV)• Stall• Higher back pressure on steam traps• Wrong sizing of steam traps

Failed closed - Repercussions

• Bypass needs to be opened which results in steam and condensate loss and we have seen it increases the fuel bill by huge amount

• Irregular Temperature Control• Product Spoilage• Decrease in Heat Output• Damage to Plant Equipment

Steam wastage through leaking steam trapsTrap size

Avg. ori fice size in steam traps (mm)

Steam loss ( kg/h)3bar g 6 bar g 8 bar g 14 bar g

DN15 3.0 8 13 20 38

DN20 5.0 24 40 58 100

DN25 7.5 55 100 130 200

DN40 10.0 98 180 220 380

DN50 12.5 155 200 370 580

Trap monitoring methods

• Visual Inspection.• Temperature checking done manually (hot or cold

condition checked)• Sight glass. It enables the maintenance personnel to

visually check the health of the traps.• Ultra sonic method. • Spirax Spiratec Wired Steam trap monitoring system

Limitations of manual checking

• These methods are based on spot checking and the trap is believed to be “OK” until checked the next time.

• Manual checking is prone to errors and dependent on experience of the personnel.

• Generally a few traps are checked and the results applied to the whole lot.

• Some methods (ultrasonic) are very tedious and tiring and need training of personnel. It is very inaccurate if done by untrained personnel.

Current Scenario – Industrial Trap Monitoring• Industry focus on Trap Monitoring currently is once a

month at the best ( Many industries do yearly!)

• Existing solution - R 2 T trap monitor, Handheld Units ( acoustic)

• Shortcomings - Local display, wiring hassle, intermittent monitoring, No centralised data base to asses overallhealth of plant steam trapping – All resulting in huge energy loss and poor process and end product quality !

• No on line data base management system to provide proper MIS to assess energy loss hence oil / monetary loss of process plants!

- The solution???

Innovative Solution by Forbes Marshall

Forbes Marshall Innovative Solution• Wireless Trap Monitoring System (WTMS)

– WTMS is a network for monitoring the health of Steam Traps at dispersed locations in a plant.

– It is a wireless network of Steam Traps which• alerts when there is Steam Leak in trap.

• Alerts when trap water logs without condensate removal.• Monitors condensate temperature online.

Features of WTMS:• First in India.• Online energy loss or savings due to Steam Trap Leak.• Wireless Trap Monitoring System enables

– Immediate action by end user.– Reduction in Steam Loss.– Reduction in product rejections and process downtime.

• Centralized web based Graphical Interface• Traps Database Management according to Area, Type, Faults, Pressure &

Temp, Sizes.• Online Data analysis gives Steam Loss, Monetary Loss – Daily, Monthly,

Yearly basis.• Trap Health Analysis.• Different Analysis Reports enables user to take decision on Plant

Maintenance.

Benefits of WTMS

• Prompts immediate action by end user.• Reduction in Steam Loss.• Reduction in product rejections and process downtime.• Wireless Network of Traps – No need of cabling to

remote trap locations• Centralized web based monitoring enables reduced

operator interference and data available on the internet any time.

• Battery operated – no need of any power source, plus long battery life – 4 to 5 years.*

• Different Analysis Reports enables user to take decision on Plant Maintenance.

• Application -• Multi Utility Reactors in Pharma Industry • Textile Dyeing Industry

• Conventional - Ball Float Traps with condensate Drained

Specific Concernsin Condensate Recovery

in Bulk Drug/API/Chemical Plants

• Single Jacket / Coiled Multi-Utility reactors• Separation of heating and cooling utilities • Fear of Contamination of condensate due

mixture of cooling utilities with it.• Boiler Pitting due to contaminated

condensate• Batch type processes – Varying loads

Spirax Solution:Condensate Recovery System

with UAM & CCDS

• UAM will separate condensate from other utilities & enable recover and reuse condensate & its heat based on Temperature.

• CCDS will separate condensate from other utilities & enable recover and reuse condensate & its heat based on Conductivity.

Utility Automation Module

Why UAM?• Certain process reactions requires both heating as well as

cooling cycle• General opinion is that , this condensate can’t be recovered• Separation possible by channeling condensate & cooling media

into different return lines• Constantly sensing the temperature and separating heating &

cooling media• Controller (R2V) will compare the set point and temperature

sensed by RTD & accordingly controls the valve and also monitors trap Failure.

• Control Valve (PAV) then channelize the heating & cooling media into different return lines

`

OPEN

The Cycle continues….

• The same cooling cycle follows and brine is let in which is between -5’C to -20’C

• The left over brine in the jacket gets mixed with the incoming steam and the condensate temperature which is below 95 ‘C is drained thru the cooling utilities PAV and the purer condensate is recovered.