tube fitting manufacturer

Ball valve and needle valve using method and USES: what are the different ball valve is evolved by the cock valve. It has the same rotated 90 °, the different is the cock body is ball, a round hole or channel through its axis. Spherical tube fitting manufacturer and opening ratio should be such, that is when the ball rotated 90 °, should all present in the inlet and outlet sphere, thus cutting fluid flow.
Needle valve: the valve is a throttling valve, adjusting precision is higher. Valve needle, along the flow direction of movement, change the flow area, to truncate or flow adjusting valve. Needle valve is a kind of fine-tuning valve, the valve plug for needle, mainly used for adjusting the gas flow. Fine-tuning require valves open mouth increases gradually, from closed to open for finely adjusted. Needle valve plug after quenching is commonly used in steel needle, and the seat is made of tin, copper and other soft materials. Asked needle valve and valve seat sealing work closely rely on the cone. Needle valve with the taper 1:50 and cone Angle of 60, cone surface after fine grinding. The valve stem and valve seat asked seal are realized by bellows.
The difference between the ball valve and needle valve, needle valve can adjust flow, 14 tube fitting the size of the ball valve can not adjust flow; Needle valve fully open need to turn the screws round and round the handle, and only turn 90 ° to ball valve. On the shape difference is more apparent, needle valve handwheel, ball valve has a hand. In liquid, air pressure control for flow adjusting the needle valve in the pipeline, if quick truncation flow ball valve.
Needle valve test pressure to high pressure in extinguishing the fire within 5 min, needle valve, pressure water cooling test makes its external surface temperature is less than 100 degrees; Cooling time is not more than 10 min, record the pressure water cooling surface of the valve. This process makes it less than 100 degrees. Check and adjust the test pressure pipe fittings manufacturer with 2.5.2.4 (4) is consistent, the reading on the record the level 4, determine the water inside the container to 18, record any external leakage of pressure relief devices, if the connection is as part of the standard design. This leakage is used to calculate all the leakage during the burning and cooling period. For the nominal pressure PN 100 (Class600) type needle valve, reduce and stabilize pressure is 0.2 MPa (2 bar), in 5 min time measured by the seat of the leakage. Increase and stabilize the test pressure to high pressure, 15, close the valve test according to the test pressure control valve to the fully open position. Stable pressure and the high test pressure, and measuring the leakage of 5 min time.