Classification and use of marine valves
Sep 06, 2021
According to the channel direction of the stop valve, it is divided into:
1) Straight-through globe valve
2) Direct-flow stop valve: In direct-flow or Y-shaped stop valve, the flow passage of the valve body is in a diagonal line with the main flow passage, so that the damage degree of the flow state is smaller than that of the conventional stop valve, so the pressure loss through the valve is also corresponding Is too small.
3) Angle type stop valve: In the angle type stop valve, the fluid only needs to change its direction once, so that the pressure drop through this valve is smaller than that of the conventional structure of the stop valve.
4) Plunger type globe valve: This type of globe valve is a variation of the conventional globe valve. In this valve, the disc and valve seat are designed based on the plunger principle. The valve clack is polished so that the plunger and the valve stem are connected, and the sealing is achieved by two elastic sealing rings sleeved on the plunger. The two elastic sealing rings are separated by a sleeve ring, and the sealing ring around the plunger is pressed firmly by the load exerted on the bonnet by the bonnet nut. The elastic sealing ring can be replaced and can be made of various materials. The valve is mainly used for "open" or "close", but it is equipped with a special form of plunger or special collar, which can also be used to adjust the flow rate. .
According to the position of the thread on the stem of the globe valve, it can be divided into:
1) Upper threaded stem stop valve: The thread of the stem of the stop valve is on the outside of the valve body. The advantage is that the valve stem is not corroded by the medium and is convenient for lubrication. This kind of structure is more common.
2) Bottom thread stem stop valve: the thread of the stem of the stop valve is in the valve body. The stem thread of this structure is in direct contact with the medium, which is susceptible to corrosion and cannot be lubricated. This structure is used in small diameter and low temperature places
