Steam trap test method

Steam traps are tested in the following ways:

1. Shell test a) Test media: water, kerosene, or other liquids with a viscosity no greater than water;

b) Test pressure: 1.5 times the nominal pressure;

c) medium temperature: normal temperature;

d) Apply test pressure to traps that are assembled and closed at the inlet and outlet ends. During the time specified in Table 1, the casing shall not leak and the internal parts shall not have residual deformation.

Nominal diameter/DN test duration/s

≤50>15

65～150>60

Note: When using steam, air and other gas tests, there should be safety measures, and approved by the relevant departments.

2. When the action test is used to connect the steam trap to the steam, the trap should be closed. When a certain load rate of hot condensate water is introduced, the trap should be opened (the time required for opening varies with the type of trap), and the condensate drains. The trap should be closed again. Perform at least 3 full cycles and this test is completed.

Mechanical traps with sealing sub below the sealed float and designed water seal function can be tested with air and water.

For disc-type steam traps, when the inlet is in the complete steam state, the frequency of valve flapping is not more than 3 times/min.

For subcooled traps, the degree of shutdown undercooling is not greater than the design given value.

3, the minimum working pressure test according to the provisions of 2 action test, while gradually reducing the test pressure, until the minimum working pressure. The trap should be able to open and close properly throughout the test.

4, the maximum working pressure test According to the provisions of 3.2 action test, while gradually increasing the test pressure until the maximum working pressure. The trap should be able to open and close properly throughout the test.

5, the highest working back pressure test Under the maximum working pressure according to the provisions of the 3.2 test operation, while gradually increasing the pressure at the outlet end of the trap, until the trap can not open and close properly. The maximum outlet pressure at which the trap can be opened and closed correctly is the maximum working back pressure.

6, the air capacity test will not exceed 0.3MPa air pass trap, the trap should be able to discharge air, allowing the trap to shut off briefly within 5min, but the closing time shall not exceed 1min.

7. Drainage temperature test Pass the steam to the trap to shut it off, then introduce the condensate at saturation temperature. If the trap cannot be opened immediately, wait until the trap cools slowly until the trap opens automatically. The inlet condensate temperature at opening is the valve opening temperature. Then gradually increase the temperature of the condensate until the trap closes automatically. The temperature of the inlet condensate at closing is the valve closing temperature.

8. The steam leakage test introduces hot condensate with a load rate of (6 ± 3)% to the steam trap at a given working pressure. At the same time, it sends saturated steam and drains the condensate drained into the trap to the specified capacity. In the barrel, the heat balance method is used to calculate the amount of steam leakage. The test method for steam leakage is as specified in Appendix A.

9. Thermal condensate discharge test The thermal condensate discharge is the weight of the hot condensate discharged per unit of time measured at a certain pressure differential and condensate temperature. Thermal condensate discharges under different pressure differentials should be measured at the same degree of undercooling. Under normal circumstances, the heat condensate discharge test can make the outlet end of the trap open to the atmosphere. Thermal condensate discharge test method according to the provisions of Appendix B.