Why steam trap survey?

Transcription

1 Why steam trap survey? Why does our customer need to have a steam trap survey regularly? Leaking steam trap wasting steam away steam boiler keep producing steam that will be wasted away Blocked steam trap will create condensate flooded inside the steam heating equipment Heating efficiency of the steam heating equipment drops steam boiler keep producing steam that will be wasted away in a non-efficient heating system Replacing the faulty steam trap means productivity increases & saving cost!

2 Why is steam trap always faulty Why steam trap is always? faulty after sometimes? Dirt steam trap blocked (plugged) Sudden pressure surge damage the steam trap mechanism Oversize steam trap the condensate capacity coming into the steam trap is much-much lower than the real condensate capacity of the steam trap resulting valve & seat chattering frequent chattering contact between valve & seat will wear the steam trap mechanism faster!

3 How to conduct a steam trap survey? How to conduct a steam trap survey? Visually check! Whether the stop valves at the upstream & downstream of the steam trap have already open Check the steam trap with a thermometer/thermal imager 1. If cold Could be steam trap is plugged close or no steam coming into the system at all 2. If hot Could be steam trap is working properly or steam trap is fail open (leaking) Check steam trap with ultrasonic checker To see whether the steam trap is operating properly

4 Visual checking What about visual checking # 1? Check whether the steam trap is installed in a closed loop condensate system If YES Please check is there any sight glass installed at the outlet of the steam trap Check whether the steam trap outlet is installed in an open loop condensate system (the condensate is drained out from the steam trap to the open atmosphere/drainage) Condensate closed loop Condensate open loop

5 Visual checking What about visual checking # 2? Check whether the steam trap piping consist of: Inlet stop valve, Y-strainer, outlet stop valve & bypass valve or NOT Scenario # 1 Scenario # 4 Scenario # 2 Scenario # 3 Scenario # 5

6 Visual checking What about visual checking # 3? Check whether the stop valves at the upstream & downstream of the steam trap have already open If there is a bypass stop valve Make sure the bypass stop valve is closed 6

7 Visual checking What about visual checking # 4? Check steam pressure at the inlet of the steam trap (P-I) In the below sketch The P-I pressure is the same as the steam pressure inside the heat exchanger (steam heating equipment) Check condensate lift/back pressure at the outlet of the steam trap (P-O) In the below sketch The P-O pressure is the same as the back pressure of the condensate inside the pipeline going to the condensate return line If the steam trap outlet is open to atmosphere (drain out to drainage) P-O = 0 bar 7

8 Temperature checking What about temperature checking # 1? Check the steam trap temperature with thermal imager

9 Temperature checking How to know the steam trap temperature is OK? Please check the steam trap temperature based on the below table of Pressure-Temperature relationship of saturated steam NOTE: If the temperature of the steam trap is below 100 C Something is wrong!

10 Temperature checking What about temperature checking # 3? If steam trap temperature is COLD (below 80 C) It could be: Steam trap is blocked/plugged by dirt (closed) It will create condensate flooded at the upstream of the steam trap Check also the temperature of the steam piping before the steam trap as a counter-check FLOODED Steam trap Is cold

11 Temperature checking What about temperature checking # 4? If the temperature of the steam trap is HOT Proceed with ultrasonic steam trap checking

12 The noise coming out of a steam trap? How to check the noise coming out of various type of steam trap with ultrasonic checker? Inverted bucket steam trap operation Intermittent (on-off) Thermodynamic disc steam trap operation Intermittent (on-off) Thermostatic bellow & Bimetallic steam trap operation Intermittent (on-off) Float & thermostatic steam trap operation Continuously

13 Inverted bucket ST ultrasonic checking Inverted bucket steam trap ultrasonic checking? The noise comes out of the ultrasonic checker must be intermittent We can see also the dial movement at the indicator of the ultrasonic checker Steam trap is closed Steam trap is open

14 Inverted bucket ST ultrasonic checking Inverted bucket steam trap ultrasonic checking? We have to put the sensor probe at the outlet connection of the steam trap

15 Inverted bucket ST ultrasonic checking Inverted bucket steam trap ultrasonic checking? We can see also the dial movement at the indicator of the ultrasonic checker Could be the steam trap is OVER-sized This will create steam trap wear faster!

16 Inverted bucket ST ultrasonic checking Inverted bucket steam trap ultrasonic checking? We can see also the dial movement at the indicator of the ultrasonic checker

17 Inverted bucket ST ultrasonic checking Inverted bucket steam trap ultrasonic checking? We can see also the dial movement at the indicator of the ultrasonic checker To check whether the steam trap is still OK Close the stop valve at the outlet of the steam trap for sometimes (to let condensate built-up inside the trap body) Open the stop valve Check whether the steam trap is OK now by draining the condensate intermittently!

18 Inverted bucket ST ultrasonic checking Inverted bucket steam trap ultrasonic checking? We can see also the dial movement at the indicator of the ultrasonic checker

19 Thermodynamic disc ST ultrasonic Thermodynamic disc checking steam trap ultrasonic checking? The noise comes out of the ultrasonic checker must be intermittent We can see also the dial movement at the indicator of the ultrasonic checker Steam trap is closed Steam trap is open

20 Thermodynamic disc ST ultrasonic checking Thermodynamic disc steam trap ultrasonic checking? We have to put the sensor probe at the outlet connection of the steam trap

21 Thermodynamic disc ST ultrasonic checking Thermodynamic disc steam trap ultrasonic checking? We can see also the dial movement at the indicator of the ultrasonic checker

22 Thermodynamic disc ST ultrasonic checking Thermodynamic disc steam trap ultrasonic checking? We can see also the dial movement at the indicator of the ultrasonic checker A good steam trap cycle about 5 6 X per/minute Bad steam trap cycles about more than 10 X per/minute NOTE: If thermodynamic disc steam trap is installed outdoor It is better to have a rain cover on top of the trap (IF NOT the steam trap will open & close very fast during raining)

23 Float steam trap ultrasonic checking Float steam trap ultrasonic checking? The noise comes out of the ultrasonic checker must be continuous We can see also the dial movement at the indicator of the ultrasonic checker Steam trap is open continuously

24 Float steam trap ultrasonic checking Float steam trap ultrasonic checking? We have to put the sensor probe at the outlet connection of the steam trap and at the thermostatic air vent element location NOTE: Air vent is the thermostatic element (bellow or bimetal)

25 Free float steam trap ultrasonic checking Free float steam trap ultrasonic checking? We have to put the sensor probe at the outlet connection of the steam trap and at the thermostatic air vent element location NOTE: Air vent is the thermostatic element bellow or bimetal)

26 Float steam trap ultrasonic checking Float type steam trap ultrasonic checking? We can see also the dial movement at the indicator of the ultrasonic checker

27 Float steam trap ultrasonic checking Float type steam trap ultrasonic checking? We can see also the dial movement at the indicator of the ultrasonic checker Mostly, float type of steam trap will discharge condensate continuously! So it is a bit difficult to differentiate is: The steam trap is working OK or The steam trap is leaking (blow thru)

28 Float steam trap ultrasonic checking Float type steam trap ultrasonic checking what happen if we are not sure the steam trap is OK or leaking? 1. Set the ultrasonic detector sensitivity adjuster to 50 % only 2. Point the probe of the ultrasonic checker at the steam trap outlet connection (point # 1) Record the result 3. Point the probe of ultrasonic checker at the downstream pipe after the steam trap (about cm distance) Record the result If the noise is lessen steam trap is in good condition If the noise is the same Steam trap is leaking Test Point no 1 Test Point no cm

29 Float steam trap ultrasonic checking Float type steam trap ultrasonic checking? We can try this too: 1. Close the isolation valve after the steam trap for sometimes 2. The condensate will build-up inside the float steam trap 3. Open the isolation valve after the steam trap 4. Observe the noise of the steam trap if the noise become bigger after sometimes the steam trap is leaking

30 Thermostatic steam trap ultrasonic checking Thermostatic steam trap ultrasonic checking? The noise comes out of the ultrasonic checker must be intermittent We can see also the dial movement at the indicator of the ultrasonic checker Steam trap is closed Steam trap is open

31 Thermostatic bellow ST ultrasonic checking Thermostatic bellow steam trap ultrasonic checking? We have to put the sensor probe at the outlet connection of the steam trap and at the thermostatic air vent element location

32 Thermostatic bimetal ST ultrasonic checking Thermostatic bimetal steam trap ultrasonic checking? We have to put the sensor probe at the outlet connection of the steam trap and at the thermostatic air vent element location

33 Thermostatic steam trap ultrasonic checking Thermostatic steam trap ultrasonic checking? We can see also the dial movement at the indicator of the ultrasonic checker

34 Thermostatic bimetal ST ultrasonic checking What is the most application of thermostatic bimetal steam trap?? Thermostatic bimetal steam trap are mostly used for superheat steam application Since the superheat steam piping is very dry We can spray the thermostatic bimetalic steam trap with water to check whether it is working or not Superheat lines do not theoretically have condensate in them and therefore should not require the use of steam trap. The primary reason for steam traps on the superheat system is the cold water start-up load It can be heavy because of the large size of the main.