The structural forms of the stop valve body include straight through type, direct flow type and right angle type. Dalian marine valve through type is a common structure, but its fluid resistance is large. Direct flow fluid resistance is small, and it is mainly used for fluids with solid particles or high viscosity. The right angle valve body is mostly forged, which is suitable for the globe valve with small passage and high pressure.
1) Straight cut-off valve
2) Direct flow stop valve: in the direct flow or Y-shaped stop valve, the flow channel of the valve body and the main flow channel form an oblique line, so the damage degree of the flow state is smaller than that of the conventional stop valve, so the pressure loss through the valve is correspondingly small.
3) Angle stop valve: in the angle stop valve, the fluid only needs to change direction once, so that the pressure drop through the valve is smaller than that of the conventional stop valve.
4) Plunger type stop valve: this type of stop valve is a variation of the conventional stop valve. In this valve, the disc and seat are usually designed based on the plunger principle. The valve disc is polished into a cylindrical plug and connected with the valve stem. The sealing is realized by two elastic sealing rings sleeved on the plunger. The valve is mainly used for "on" or "off", but it is equipped with a special plunger or special collar, which can also be used to regulate the flow.
Stop valve refers to the valve whose closing member (disc) moves along the center line of the valve seat. According to this movement form of the valve disc, the change of the valve seat opening is in direct proportion to the valve disc stroke. Because the valve stem opening or closing stroke of this type of valve is relatively short, and it has a very reliable cut-off function, and because the change of the valve seat opening is proportional to the stroke of the valve disc, it is very suitable for regulating the flow. Therefore, this type of valve is very suitable for cutting off or regulating and throttling.