1. ©2008 Armstrong International, Inc. Basic Steam Trap Operation

2. What MUST a Steam Trap do? A Steam Trap must remove condensate, air, and CO 2 out of the system as quickly as it collects. 2 “Expect many enjoyable experiences!” David M. Armstrong ®

3. 3 “Expect many enjoyable experiences!” David M. Armstrong ® Minimize steam lose Corrosion resistance CO 2 Venting Freedom from dirt problems Long life and dependable service Air Venting Operation against backpressure A Steam Trap Must Also:

4. 4 “Expect many enjoyable experiences!” David M. Armstrong ® What makes up a Steam Trap A Steam Trap has an orifice An orifice alone is not a steam trap –If flow changes, orifice is not correct –If pressure drop changes, orifice is not correct –The orifice must change size as conditions change Orifice Inlet Connection Outlet Connection Body

5. 5 “Expect many enjoyable experiences!” David M. Armstrong ® What makes up a Steam Trap A Steam Trap should have a valve –A valve may be fully opened and fully closed or modulated to vary the size of the orifice as conditions change Orifice Inlet Connection Outlet Connection Body Valve

6. 6 “Expect many enjoyable experiences!” David M. Armstrong ® What makes up a Steam Trap A Steam Trap should have an Operator –An operator senses when to move the valve and supplies the power to move the valve –Traps are different in the types of valve and the types of operator they use Inlet Connection Outlet Connection Body Valve Orifice Operator

7. Trap/Operator Types Mechanical Use difference in density between steam and condensate to operate valve. A float operates the valve. Thermodynamic Steam (flash) – flow operates valve Thermostatic Sense temperature change of condensate to operate valve 7 “Expect many enjoyable experiences!” David M. Armstrong ®

8. 8 “Expect many enjoyable experiences!” David M. Armstrong ® Thermostatic Trap Types Bellows balanced pressure –High capacity Wafer/Diaphragm balanced pressure –Low capacity Bi-metallic –High and low capacity

9. 9 “Expect many enjoyable experiences!” David M. Armstrong ® Bellows Balanced Pressure Steam Condensate Liquid fill Bellows Valve Seat

10. 10 “Expect many enjoyable experiences!” David M. Armstrong ® Bellows Balance Pressure Bellows Balance Pressure Modulation Poor Backpressure Good Dirt Fair Wear Fair Water Hammer Poor Freezing Good

11. 11 “Expect many enjoyable experiences!” David M. Armstrong ® Simple Bi-Metal Element High expansion metal Low expansion metal Cold Hot

12. 12 “Expect many enjoyable experiences!” David M. Armstrong ® Simple Bi-Metal Operation Valve inside trap Pressure holds valve closed; valve toggles Back pressure can blow trap open Opening and closing temperatures wide apart Must sub-cool deeply to prevent steam loss

13. 13 “Expect many enjoyable experiences!” David M. Armstrong ® Bi-Metal Disks Valve in outlet Pressure opposes closing. Does not toggle. Some thermodynamic action; roughly follows steam saturation curve. Acts as check valve when pressure is lost. Good for use in super- heated applications.

14. A.Trap body B.Disk bonnet C.Disk D.Inner seat ring E.Outer seat ring F.Inlet port G.Outlet port and groove Disk Trap Orifices in Series P2 A B C D E FG H D E F G H E D P1 P3

15. 15 “Expect many enjoyable experiences!” David M. Armstrong ® Disk Trap Start-up Condensate pressure pushes disk off seat Full capacity flow Two pressure drops

16. 16 “Expect many enjoyable experiences!” David M. Armstrong ® Disk Trap Flashing Steam Condensate near steam temperature flashes to steam in inlet port Pressure drops with flow through restriction under disk Pressure difference (P2 - (<<P2)) slams disk onto seats P1 P2 <<P2 P3

17. 17 “Expect many enjoyable experiences!” David M. Armstrong ® Disk Trap Closed P2 – P3 x disk area > P1 x inlet port area + P3 x outlet port area Closing force greater than opening forces so disk stays on seat Condensing flash steam above disk relieves pressure until opening forces are greater; disk snaps open A bleed groove is used to help with control of the pressure in the control chamber.

18. 18 “Expect many enjoyable experiences!” David M. Armstrong ® Disk and Seat Wear Disk slammed hard onto seats and rolls as it seats –Edge of disk wears rapidly –Edge of outer seat ring wears rapidly High velocity flow of condensate flash steam and dirt between disk and inner seat ring –Inner seat ring wears rapidly –Disk surface erodes rapidly Uneven contact of disk on seat causes wear Disk Wear Seat Wear Flat valve and seats require near perfect flatness to seal Two seats to seal

19. 19 “Expect many enjoyable experiences!” David M. Armstrong ® Thermodynamic Traps Bellows Balance Pressure Thermodynamic Traps Modulation PoorFair Backpressure GoodPoor Dirt FairPoor Wear FairPoor Water Hammer PoorGood Freezing Good

20. 20 “Expect many enjoyable experiences!” David M. Armstrong ® Mechanical Types Float & Thermostatic Inverted Bucket Linkage Fixed Pivot Air Vent Valve Valve Ball Seat

21. 21 “Expect many enjoyable experiences!” David M. Armstrong ® Simple Float Trap Fixed Pivot Air Vent Valve Valve Ball Seat Linkage

22. 22 “Expect many enjoyable experiences!” David M. Armstrong ® Float and Thermostatic Condensate enters Ball rises opening valve to full capacity Bellows cold; vent open to air and/or condensate flow Condensate flow decreases Ball moves downward; valve open less Valve modulates to balance outlet flow = inlet flow Steam enters; steam air mixture closes vent; temperature below saturation Start-Up Modulating Air Venting Air increases; temperature drops; vent opens Steam lost with air removal Dirt falls to bottom; may stop ball from dropping holding valve open; may plug valve

23. 23 “Expect many enjoyable experiences!” David M. Armstrong ® F&T Traps Bellows Balance Pressure Thermodynamic Traps F&T Traps Modulation PoorFairGood Backpressure GoodPoorGood Dirt FairPoor Wear FairPoorGood Water Hammer PoorGoodPoor Freezing Good Poor

24. 24 “Expect many enjoyable experiences!” David M. Armstrong ® Inverted Bucket A.Bucket B.Valve on linkage Sized for maximum flow at maximum pressure difference C.Air Vent D.Body Material based on pressure and cost E.Inlet D C B A E Bottom inlet – Top outlet Other configurations available

25. 25 “Expect many enjoyable experiences!” David M. Armstrong ® IB At Start-Up Low velocity flow Condensate fills body Condensate surrounds all internals; pressure same on all surfaces of all internals; no water hammer damage Valve wide open for maximum flow rate; quick drain Air pushed out ahead of condensate through wide open valve; quick vent Small dirt particles suspended in flow and flushed through valve Large dirt particles are too heavy to be carried to valve by low velocity flow around bucket lip, so they stay at bottom No strainer needed in most applications Condensate Valve wide open

26. 26 “Expect many enjoyable experiences!” David M. Armstrong ® IB Closed Start-up condensate accumulation gone Steam enters depressing water level in bucket When bucket approximately 2/3 full of steam, bucket becomes buoyant Bucket floats valve to seat Pressure difference pushes valve softly into seat Valve seats tightly Air passes through vent to collect at top of trap Condensate level Valve tightly closed

27. 27 “Expect many enjoyable experiences!” David M. Armstrong ® IB Filling Valve closed; condensate continues to enter trap; no condensate back-up Intermittent discharge but continuous drain Water condenses and displaces steam; water level rises Air continually rises through vent to top of trap If air accumulation becomes excessive, air will depress water level and open valve Condensate Valve tightly closed Steam

28. 28 “Expect many enjoyable experiences!” David M. Armstrong ® IB Opening Small dirt flushed Valve wide open Water level continues to rise Bucket 2/3 full of water loses buoyancy; bucket falls pulling valve wide open Air flushed out Full capacity flow carries small dirt particles to wide open valve to flush each cycle Pressure changes affect capacity only Steam in trap continuously; condensate and air discharged at steam temperature Cycle rate adjusts immediately with flow changes

29. 29 “Expect many enjoyable experiences!” David M. Armstrong ® IB Thermic Vent Bi-metal thermic vent Open at start-up for quick vent of air under bucket Closed at steam temperature; normal vent enough for operating air venting load

30. 30 “Expect many enjoyable experiences!” David M. Armstrong ® Inverted Bucket

31. 31 “Expect many enjoyable experiences!” David M. Armstrong ® Armstrong Promise We provide intelligent system solutions that improve utility performance, lower energy consumption, and reduce environmental emissions... while providing an “enjoyable experience”! 31 “Expect many enjoyable experiences!” David M. Armstrong ®

32. 32 “Expect many enjoyable experiences!” David M. Armstrong ®

33. ©2008 Armstrong International, Inc.