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中文简体1. According to the channel direction of the globe valve, it is divided into:
1) Straight-through globe valve
2) DC globe valve: In the DC or Y-shaped globe valve, the flow channel of the valve body forms a diagonal line with the main channel, so that the degree of damage to the flow state is smaller than that of the conventional globe valve, so the pressure loss through the valve is also corresponding. 's small.
3) Angle globe valve: In the angle globe valve, the fluid only needs to change direction once, so that the pressure drop through the valve is smaller than that of the conventional structure globe valve.
4) Plunger globe valve: This form of globe valve is a variant of the conventional globe valve. In this valve, the disc and seat are usually designed based on the plunger principle. The valve disc is polished so that the plunger is connected with the valve stem, and the sealing is realized by two elastic sealing rings sleeved on the plunger. The two elastomeric seals are separated by a collar and compress the seal around the plunger by the load applied to the bonnet by the bonnet nut. Elastomeric seals are replaceable and can be made of a variety of materials, the valve is mainly used for "open" or "closed", but is available with special forms of plungers or special collars and can also be used to regulate flow .
2. According to the position of the thread on the stem of the globe valve, it can be divided into:
1) Upper threaded stem globe valve: The thread of the globe 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. This structure is relatively common.
2) Lower threaded stem globe valve: The thread of the globe valve stem is in the valve body. The stem thread of this structure is in direct contact with the medium, which is easily corroded and cannot be lubricated. This structure is used in places with small diameters and low temperatures.
There are many domestic manufacturers of globe valves, and most of the connection sizes are not uniform. Mainly divided into the following categories:
1) General class based on JB/T2203-1999 "Structural Length of Globe Valve". Most domestic safety valve manufacturers are designed and produced according to this standard. However, this standard is not perfect, and the specifications are incomplete. The maximum nominal diameter of the single gate globe valve is DN1200, and the maximum nominal diameter of the double gate globe valve is DN1500. According to the specifications of the globe valve produced by the factory and the information available, the nominal diameter of the angle-type globe valve is at least DN15, and the nominal diameter of the Z-type straight-through globe valve reaches DN2000. After research, the connection size of each manufacturer is not uniform, such as DN150Z type straight-through globe valve, Shanghai Liangzhong Valve Factory, Shanghai Globe Valve Factory and Shanghai Yaze Valve Factory are different. In order to have a unified standard, users can exchange the same specifications when selecting and installing, it is recommended that China General Machinery Research Institute revise JB/T2203-1999 "Structural Length of Globe Valves". It is recommended that design institutes and users select according to the standard, and the globe valve manufacturer designs and manufactures according to the standard.
