Low middle pressure Ball valves-China Balancing valve-Safety Valve

Low middle pressure Ball valves inspecting and testing

Methods & Procedures for shell test:
Covering the entrance and exit of the valve, pressing the gland tightly to make the disc be in intermediate positions. Full filling with medium in the shell body to reach testing pressure gradually. Inspecting for the shell including the gland and union between the body and cap to see if there is leakage when reaches to stipulated time.
Testing temperature. Testing medium .Testing pressure. The shortest continued time and allowed leak rate on shell test and seal function test as following sheet.
Methods & Procedures for Seal function test:
Covering the two ends of the valve to make the disc be slight opening position and to reach to testing pressure with full medium in the shell body. Releasing the pressure of one end when closing. Doing the same with another end .Being tested by seal function to make sure without any leakage before selling into the makets.
Testing temperature. Testing medium. Testing pressure. The shortest continued time and allowed leak rate on shell test and seal function test as following sheet.

Item	Enforce standerd		allowed leak rate
Shell test	Testing pressure	2.4	no leak(no obvious dropping of surface wet)
	Continued time	15
	Testing temperature	≤125 °F （52 ℃）
	Testing medium	water
Seal function test	Testing pressure	2.4	noleak
	Continued time	15
	Testing temperature	≤125 °F （52 ℃）
	Testing medium	water