Manual Valves
12/07/2016
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The management staff of trained PGTech intensive operation mechanism of the type of valve and by the experience gained over many years working in related fields, we present an overview of the mechanisms operation of the valve body type do take mosaic materials for customers, as well as the technicians doing the same field.
According to the engineering school, Valves (Valve), a common name for a device with a feature motion mechanism opens and closes a path to allow, block or control the flow of fluids .
There are many different types of valves The different brands are used in industrial applications worldwide. The following article will cover PGTech general mechanisms and the most typical functions of the valves are used in steam systems, such as ball valves, butterfly valves, globe valves, gate valves.
Manual Van Under Construction Type
- Van turned the corridor to stop the flow (ball valves, butterfly valves)
- Valve functions as a 'sign' or 'plug' in the hallway to stop the flow (Van Cau)
- Valve function "inserted" into the aisle to stop the flow (Valve Gate).
- Valve function 'pinched' against passage from the outside to stop the flow (foot valve).
Ball valves
Ball valve interrupts the circulation solution is very good. A rotating operation (90 °) can help close or open the valve completely. This feature helps minimize operating time of the valve and reduce the possibility of leakage due to class reliability from the valve mattress.
Ball valves can be divided into two categories: traffic restrictions and open the whole line - reduced bore and full bore. In terms of passage of the valve is limited, when the valve opening is smaller than the diameter of the pipe; the entire road open valve, the valve opening is the same size as the diameter of the pipe. Ball Valves Full bore type generally valuable because they reduce pressure drop through the valve.
The movement of the valve
Balls Van (Van Bi) usually are recommended for use only in a fully open position or fully closed. It is not appropriate to adjust the flow by keeping an open section for ball valves with soft valve seats using circular ring shape. When used in the open position partly, pressure is applied to the part of the valve, which can cause valve deformation. If the substrate is deformed valve, its closed system is weakened and as a result, the valve will leak.
Butterfly valve
In the operation mechanism of the butterfly valve, the flow is adjusted through a drive mechanism is held in the center of the valve by a lever arm. Similar to the ball valve, the valve operating time is short because of the valve mechanism is simply rotate a quarter turn (90 °) to open or close the passageway.
Obtain special butterfly valve is structurally simple, light weight, and compact design. The size is usually very small interface, reducing the pressure through a throttle butterfly valve is much smaller than the demand (see below). Materials used for the components of the valve may limit the application of the valve at higher temperatures, or some kind of liquid. Butterfly valves are often used on applications for water and air, and in applications with larger pipe diameter.
The globe valve is suitable for use on a wide range of applications, from controlling the flow rate to help either closed or open flow.
In this contest bridge valves controlling the flow rate is determined not by the size of the opening of the valve seat, which is due to pick up the rhythm of the valve button (the distance from the location of the valve is lifted from the valve seat) . The valve features even when the bridge is used in place partially open, there is less risk of damage or closing the valve by valve liquid than other valves. In many aspects of the application, the first type of needle valves are particularly suitable for controlling the flow rate.
Other points to consider about the pressure drop through the valve in the valve is larger than many other types, since it is shaped S. Time of valve operation and longer because the valve body must be turned several times to open and close valves, and this can cause leakage of the buffer (buffer latch). Furthermore, users must be careful not to leave the valve shaft too far because of the possibility it could damage the surface of the valve seat.
valve Gate
The construction of a gate valve is similar to that of a floodgate (sewer discharge): Traffic is controlled by raising or lowering the valve, which are generally under 3 modes: strong, flexible, and splits . Two categories help prevent deformation of the first valve body and the valve due to different operating conditions.
Like ball valves, gate valves are often not used to regulate the flow. One of the reasons for this is because the valving element can be damaged when the gate valve is opened only partially. Similarly, ball valve also limits the pressure drop through the valve when the valve fully open. However, put the valve into a fully open position or close requires processing to be shot multiple times, which often makes the gate valve with the longest operation time of the valves mentioned in articles about this valves.