1, Valve Installation

Valve installation of the best use of the rings installed, the use of chain installation, attention to the valve coating to take protective measures. When the valve with bracket or transmission mechanism, the hanging rope should be fixed on the valve rings, can not be placed on the transmission mechanism, hanging rope or hoisting chain can not squeeze the external parts of the valve and extension rods, so as not to damage valve actuator, resulting in valve can not switch or switch difficult.

2, Valve welding

(1) After the valve is in place, in the valve preheating and welding, valve should be placed in full open position, otherwise, in the welding process, the ball valve ball and gate valve of the gate will be stained with solder slag, when put into production, these attached slag will scratch the seat seal, resulting in valve leakage, serious will lead to valve failure.

(2) The valve must be supported on the respective base or separately supported.

(3) After the valve welding, if the need to rotate the valve, you should use the manual grease gun filling and lubricating.

(4) To confirm the discharge port, discharge pressure mouth in the closed state.

(5) General ball valve installation without directionality, but should pay attention to the location of the operation side. Some ball valve installation with directional, must follow the valve body on the arrow logo to install, can not be reversed. For example, the Western pipeline of crude oil, part of the product oil station of the import and export side of the ball valves are two types of seat seals, one end of the use of dual-piston effect of the seat, the other end of the use of the vent-type sealed valve seat, if the reverse installation, after the valve will be automatically released pressure, pipeline accident.

3, after the valve welding requirements

(1) After the valve in the welding test pressure, should inject grease, to ensure that the valve sealing surface is filled with grease, will be welded to the valve seat sealing surface impurities with grease discharge.

(2) Check the valve status, to ensure that the external joints are locked, no loosening, to confirm the sewage outlet, pressure vent in a locked state, for pressure test preparation.

(3) operate the valve according to the pressure test plan, so that the valve is in the specified position.