Xiamen Kemus Valve Co.,Ltd
Add: 5 floor, Zhimingxing Technology Building No 18, Honglian West Road, Siming District Xiamen China
1) Straight-through stop valve
2) DC type stop valve: In the DC or Y-shaped stop valve, the flow path of the valve body is inclined with the main flow path, so that the degree of damage of the flow state is smaller than that of the conventional stop valve, and thus the pressure loss through the valve is correspondingly Small.
3) Angle stop valve: In the angle cut-off valve, the fluid only needs to change in one direction, so that the pressure drop through the valve is smaller than that of the conventional structure. American standard bellows stop valve ZDAJ41W type 4) Plunger type stop valve: This type of stop valve is a variant of the conventional stop valve. In this valve, the flap and seat are usually designed based on the principle of the plunger. The valve flap is polished into a plunger that is coupled to the valve stem, and the seal is achieved by two elastomeric sealing rings that are placed over the plunger. The two elastomeric seals are separated by a collar and the seal around the plunger is pressed by the load exerted by the bonnet nut on the bonnet. The elastomeric seal can be replaced and can be made from a wide variety of materials. The valve is mainly used for "opening" or "off", but with a special form of plunger or special collar, it can also be used to regulate flow. .
the position of the thread on the stem
1) Upper threaded stem stop valve: The thread of the shutoff valve stem is outside the valve body. The advantage is that the valve stem is not eroded by the medium and is easy to lubricate, and such a structure is relatively common.
2) Lower threaded stem stop valve: The thread of the shutoff valve stem is inside the valve body. This type of stem thread is in direct contact with the media and is susceptible to erosion and lubrication. This structure is used in places with small calibers and low temperatures.
There are many manufacturers of shut-off valves in China, and the connection sizes are mostly not uniform. Mainly divided into the following major categories:
1) General class based on JB/T2203-1999 "Structural length of shut-off valve". At present, most domestic manufacturers of globe valves are designed and produced according to this standard. However, this standard is not perfect, the specifications are not complete, the maximum nominal diameter of the single gate stop valve is DN1200, and the maximum nominal diameter of the double gate stop valve is DN1500. According to the specifications of the shut-off valve produced by the manufacturer and the information obtained, the nominal diameter of the angle-type globe valve is DN15, and the nominal diameter of the Z-type straight-through globe valve is DN2000. According to research, the connection sizes of various manufacturers are not uniform. In order to have a uniform standard, the user can exchange the same specifications during the selection and installation. It is recommended that China General Machinery Research Institute revise JB/T2203-1999 "Structure Length of Globe Valve". It is recommended that the design institute and users choose according to the standard, and the manufacturer of the globe valve is designed and manufactured according to the standard.