Common valve selection and application introduction Pneumatic valve how to choose correctly

Common valve selection and application introduction Pneumatic valve how to choose correctly

The stem axis of the globe valve is perpendicular to the sealing face of the seat. Stem opening OR closing stroke is relatively short, and has a very reliable cutting action, the valve is very suitable for the use of medium cutting or regulating and throttling. The gate valve is used as a cut-off medium, the whole flow is straight through when it is fully open, and the pressure loss of the medium running is small. Ball valve is evolved from the plug valve. It has the same rotation of 90 degrees lift action, the difference is that the plug body is a sphere, with circular through holes or channels through its axis.
Selection and application of common valves
First, the selection of gate valve application
The gate valve is used as a cut-off medium, the whole flow is straight through when it is fully open, and the pressure loss of the medium running is ** * small. Gate valves are usually suitable for operating conditions that do not require frequent opening and closing, and keep the gate fully open or fully closed. Not intended for use as a regulator or throttling. For THE HIGH speed flow MEDIUM, THE gate CAN cause the gate vibration in the condition of local opening, and the vibration may damage the sealing surface of the gate and seat, and the throttle will cause the gate to suffer from the erosion of the medium. From the structural form, the main difference is the form of the sealing element used. According to the form of sealing elements, gate valves are often divided into several different types, such as wedge gate valves, parallel gate valves, parallel double gate valves, wedge double gate gates, etc. ** Commonly used forms are wedge gate valves and parallel gate valves.
Two, the selection of valve application
The stem axis of the globe valve is perpendicular to the sealing face of the seat. Stem opening OR closing stroke is relatively short, and has a very reliable cutting action, the valve is very suitable for the use of medium cutting or regulating and throttling.
Once the DISC OF the GLOBE VALVE IS IN THE open condition, there is no contact between its seat and disc sealing surface, this valve is very suitable for cutting off or regulating and throttling the use of the medium.
Once stop valve is fully open, it will no longer have a contact between the seat and clapper sealing surfaces, and thus its sealing surface mechanical wear and tear is small, because most of the cut-off valve seat and valve disc is easy to repair or replace the whole valve sealing components without removed from the pipeline, doors and pipeline welding into one occasion is very applicable. The flow direction of the medium through this valve has changed, and the force is higher than that of other valves.
Commonly used globe valves have the following:
1) Angle globe valve; In an Angle globe valve, the flow changes direction only once so that the pressure drop through the valve is smaller than in a conventional globe valve.
2) straight flow stop valve; In A STRAIGHT FLOW OR Y-SHAPED GLOBE VALVE, THE FLOW PATH OF THE BODY IS DIAGONAL TO the MAIN flow, so that the damage to the flow state is smaller than in a conventional globe valve, and the pressure loss through the valve is correspondingly smaller.
3) plunger globe valve: this form of globe valve is a variation of the conventional globe valve. In this valve, the disc and seat are usually designed based on the plunger principle. The disc is polished into a plunger connected to the stem, and the seal is achieved by two elastic sealing rings on the plunger.
A SLEEVE RING SEPARATES AND COMPRESSES THE SEALING RING AROUND THE plunGER BY a LOAD APPLIED TO THE COVER BY THE COVER NUT.
Made OF A WIDE VARIETY OF MATERIALS, THE VALVE IS PRIMARILY USED “ON” OR “OFF” BUT IS EQUIPPED WITH a SPECIAL FORM OF plunGER OR SPECIAL SLEEVE RING AND CAN ALSO BE USED TO REGULATE FLOW.
Three, the selection of ball valve application
Ball valve is evolved from the plug valve. It has the same rotation of 90 degrees lift action, the difference is that the plug body is a sphere, with circular through holes or channels through its axis. The RATIO OF THE SPHERE TO THE CHANNEL OPENING SHOULD BE SUCH THAT WHEN THE BALL IS ROTATED BY 90 DEGREES, THE SPHERE SHOULD APPEAR AT BOTH THE INLET AND outlet, THUS CUTTING OFF THE flow.
Ball valves require only a 90 degree rotation and a small rotational moment to close tightly. Completely equal valve body cavity for the medium provides little resistance, straight through the flow channel. Ball valves are generally considered suitable for direct opening and closing, but recent developments have designed them to throttle and control flow. The main characteristics of the ball valve is its compact structure, easy to operate and maintain, suitable for water, solvent, so that the valve so the globe valve flow resistance two elastic sealing ring with acid and natural gas and other general work and has a very reliable cut off dynamic elastic sealing ring can be replaced.
How to select pneumatic valve correctly
First a brief introduction to understand the pneumatic valve
Pneumatic valve is the use of compressed air drive actuator of the combined group in pneumatic piston movement and force to beam and the characteristics of the curve track, drive tubular spindle rotation, compressed air disks to each cylinder, changed the direction of gas in and out of position to change the direction of spindle rotation, according to the requirement of the load (valve) the required rotation torque, adjustable cylinder combination number, Drive the load (valve) to work.
How to select pneumatic valve correctly
First of all, we need to know the choice of pneumatic valve is to do what is commonly used in general two kinds, switch type (put on/cut off), regulating type.
Selection of parameters,
① Product name and model
② Nominal diameter
Power supply voltage
(4) working pressure difference
⑤ Use medium
⑥ Connection mode
⑦ medium temperature
⑧ Work called pressure
⑨ Operation mode (normally open, normally closed)
⑩ Do you want to bring accessories so that we can make the right type for you?
experience
Generally, the diameter of the commonly used on-off valve is not large. We will choose the pneumatic butterfly valve with the large diameter of the pneumatic ball valve. Of course, this should also be determined according to the specific operating conditions on the site.