Ball valve design recruitment

Turn it off. The design of ball valve is very intuitive. The handle of the board is perpendicular to the pipeline (transverse to the pipeline), indicating that the water is stopped and the water is flowing along the pipeline (parallel). Reminder: the ball valve should be opened and closed several times a year to prevent the valve core from rusting.

Valve is a pipeline accessory, which is used to open and close the pipeline, control the flow direction, and adjust and control the parameters (temperature, pressure and flow) of the conveying medium. According to its function, it can be divided into cut-off valve, check valve and regulating valve.

Valve is the control part in the fluid conveying system, which has the functions of cutting off, regulating, shunting, backflow prevention, pressure stabilization, shunting or overflow pressure relief. The valves used in the fluid control system, from the simplest cut-off valve to various valves used in the extremely complicated automatic control system, have quite a variety of varieties and specifications.

Valves can be used to control the flow of various fluids, such as air, water, steam, corrosive media, mud, oil, liquid metal and radioactive media. Valves are divided into cast iron valves, cast steel valves and stainless steel valves (20 1, 304, 3 16, etc. ), chrome-molybdenum steel valves, chrome-molybdenum steel valves, dual-phase steel valves, plastic valves, non-standard customized valves, etc.

Extended data:

Classification of valves

(1) Valve for cutting off and opening medium.

The flow passage is a straight-through valve with small flow resistance, and it is usually chosen as the valve to cut off and open the medium. Downward closing valves (globe valves, plunger valves) are rarely used because their flow channels are tortuous and their flow resistance is higher than other valves. When high flow resistance is allowed, the valve can be closed.

⑵ Flow control valve.

Usually, the valve that can easily adjust the flow rate is selected as the flow control valve. Downward shut-off valves (such as globe valves) are suitable for this purpose, because their seat size is proportional to the stroke of the closing member. Rotary valves (plug valves, butterfly valves, ball valves) and flexible body valves (pinch valve valves, diaphragm valves) can also be used for throttling control, but usually they can only be used in a limited range of valve diameters. Gate valve is a kind of circular valve seat with disc-shaped gate, which can control the flow well only when it is close to the closed position, so it is usually not used for flow control.

(3) Valves for reversing and shunting.

This valve can have three or more channels according to the need of reversing shunt. Plug valves and ball valves are more suitable for this purpose, so most valves used for reversing and shunting choose one of these valves. However, in some cases, other types of valves can also be used for reverse and shunt, as long as two or more valves are properly connected to each other.

(4) Valves for suspended particulate media

When there are suspended particles in the medium, when the closing part slides along the sealing surface, the valve with wiping function is most suitable. If the reciprocating motion of the closing member relative to the valve seat is vertical, particles may be trapped, so this valve is only suitable for basically clean media unless the sealing surface material allows particles to be embedded. Ball valve and plug valve can wipe the sealing surface during opening and closing, so they are suitable for media with suspended particles.

At present, whether in the pipeline system of petroleum, chemical industry or other industries, the use, working frequency and service of valves are constantly changing. In order to control or eliminate even low leakage, the most important and critical equipment is the valve.

References:

Baidu encyclopedia-valve