Three kinds of classification and selection skills of the globe valve

Commonly used globe valves are as follows:

1) Direct-flow globe valve: In the direct-flow or Y-shaped globe valve, the flow channel of the valve body is slanted to the main channel, so that the damage degree of the flow state is smaller than that of the conventional globe valve, so the pressure loss through the instrument valve is correspondingly small.

2) Angle globe valve: In the Angle globe valve, the fluid only needs to change direction once, so that the pressure drop through the instrument valve is smaller than that of the conventional structure of the globe valve.

3) Plunger type globe valve: This form of globe valve is a variation of the conventional globe valve. In this instrument valve, the disc and seat are usually designed based on the plunger principle. The disc is polished into a plunger and connected to the stem. The seal is achieved by two elastic sealing rings placed on the plunger. The two elastic seals are separated by a sleeve ring and the seal rings around the plunger are compacted by a load applied to the bonnet by the bonnet nut. The elastic seal can be replaced and can be made of a variety of materials. The instrument valve is mainly used for "opening" or "closing", but a special form of plunger or special sleeve can also be used to regulate flow. Cut-off valve selection guide: the stem axis of the cut-off valve is perpendicular to the sealing surface of the valve seat. The relatively short stem opening or closing stroke and very reliable cut-off action make this instrument valve ideal for use as a medium cut-off or regulation and throttling. Once the globe valve disc is open, there is no longer contact between its seat and the sealing surface of the valve disc, and it has a very reliable cutting action, so this instrument valve is very suitable for cutting off or adjusting and throttling the medium. Once the globe valve is in the open state, there is no longer contact between its seat and the valve disc sealing surface, so its sealing surface is less mechanical wear, because most of the globe valve seat and valve disc are easier to repair or replace the sealing element without removing the entire instrument valve from the pipeline, which is very suitable for the occasion of the instrument valve and the pipeline welded into one. The flow direction of the medium through this type of instrument valve changes, so the flow resistance of the stop valve is higher than that of other instrument valves.