1. fully welded ball valve test:

    (1) Strength test: strength test using water as medium; welding sleeves on both sides of the high-pressure valve - duh cap. The valve open position to 45 ℃, the injection of water into the ball valve by pressure test on the sleeves. Boost to 1.5 times the nominal pressure valve, pressure 15min; no leakage is qualified.

    (2) Tightness Test: Mu-tight test using nitrogen as medium; the ball valve is closed. From the sleeves pressure test valve to inject nitrogen inside the ball. Ball pressure was raised to 1.1 times the nominal pressure, cavity pressure release valve hose Walter containers that hold water for testing. The insertion depth of 1cm; produce no bubbles within 5min qualified.

    2. pipeline fully welded ball valve (Buried fully welded ball valve) installed

    (1) lifting: lifting should be the correct way valve, in order to protect the valve stem, do not sling tied to the hand wheel, gear box or actuator. Protective cap sleeves at both ends of the valve before soldering not removed.

    (2) Welding: Buried fully welded ball valve and trunk pipeline connection to take welding. Weld quality must meet the "disk flexor fusion welded joints radiography" (GB3323-2005) Ⅱ grade standard sheet, usually a welding and can not guarantee all qualified, so manufacturers should be required when ordering valves at both ends of the valves 1.0m long sleeves, if there is enough length of weld failure will be cut off and re-welding the weld failed when the ball valve and pipe welding, the valve should be at 100% of the fully open position, so as not to damage the valve ball welding slag splashing, while ensuring internal valve seal temperature up to 140 degrees Celsius, cooling can take appropriate measures when necessary.