Classification Of Stainless Steel Ball Valve

1. The stainless steel ball valves can be divided according to the structure

Floating ball valve

The ball of the ball valve is floating. Under the action of the medium pressure, the ball can produce a certain displacement and press tightly on the sealing surface of the outlet end to ensure that the outlet end is sealed. The floating ball valve has a simple structure and good sealing performance, but the load of the working medium on the ball is all transmitted to the outlet sealing ring. Therefore, it is necessary to consider whether the sealing ring material can withstand the working load of the spherical medium. This structure is widely used in medium and low pressure ball valves.

Fixed stainless steel ball valves: The ball of the ball valve is fixed and does not move after being pressed. The fixed ball valve is equipped with a floating valve seat. After receiving the pressure of the medium, the valve seat will move, so that the sealing ring is tightly pressed on the ball to ensure sealing. Bearings are usually installed on the upper and lower shafts of the ball, and the operating torque is small, which is suitable for high-pressure and large-diameter valves. In order to reduce the operating torque of the ball valve and increase the reliability of the seal, the oil-sealed ball valve appeared, which not only injects a special lubricant between the sealing surfaces to form a layer of oil film, which enhances the sealing performance and reduces the operating torque, which is more applicable High-pressure large-diameter ball valve.

Elastic stainless steel ball valves: The ball of the ball valve is elastic. The sphere and the valve seat sealing ring are made of metal materials, and the specific pressure of the seal is very large. The pressure of the medium itself cannot meet the sealing requirements, and external force must be applied. This valve is suitable for high temperature and high pressure media. The elastic sphere is made by opening an elastic groove on the lower end of the inner wall of the sphere to obtain elasticity. When closing the passage, use the wedge-shaped head of the valve stem to expand the ball and press the valve seat to seal. Loosen the wedge-shaped head before rotating the ball, and the ball will return to its original shape, so that there is a small gap between the ball and the valve seat, which can reduce the friction of the sealing surface and the operating torque.

2. Stainless steel ball valves can be divided into straight-through type, three-way type and right-angle type according to their channel position.

Three-way ball valve has T type and L type. The T-shape can connect three orthogonal pipelines with each other and cut off the third channel, which can split and merge. The L-shape can only connect two orthogonal pipes, and cannot maintain the third pipe to communicate with each other at the same time. It only plays a role of distribution.

The three-way ball valve adopts an integrated structure in structure, with a four-sided valve seat sealing type, fewer flange connections, high reliability, and a lightweight design.

The three-way ball core is divided into T type and L type, with long service life, large circulation capacity and low resistance

The stainless steel ball valves is divided into two types: single-acting and double-acting according to the action type. The single-acting type is characterized in that once the power source fails, the ball valve will be in the state required by the control system.

3. The ball valve can be divided into one-piece type, two-piece type and three-piece type according to its composition.

Using Instructions

1. Make sure that the pipeline and valve have been flushed before operation.

2. The operation of the valve drives the valve stem to complete rotation according to the size of the input signal of the actuator: when it rotates 1/4 turn (900) in the forward direction, the valve is closed. When the reverse rotation is 1/4 turn (900), the valve opens.

3. When the direction indicator arrow of the actuator is parallel to the pipeline, the valve is in the open state; when the indicator arrow is perpendicular to the pipeline, the valve is in the closed state.

Repair

Having a long service life and maintenance-free period will depend on the following factors: normal working conditions, maintaining a harmonious temperature/pressure ratio, and reasonable corrosion data