What is a Butterfly Valve?

Butterfly valve, also known as flap valve, is a simple structured regulating valve, which can be used for the switch control of low-pressure pipeline media. The closing valve (disc or disc) is a disk that rotates around the valve shaft to achieve opening and closing. Kind of valve.

Butterfly valve common fault

The rubber elastomer in the butterfly valve will cause tearing, abrasion, aging, perforation and even shedding during continuous use. However, the traditional thermal vulcanization process is difficult to meet the needs of on-site repair. Special equipment is used during the repair, which consumes a lot of heat and electricity, which is time-consuming and labor-intensive. Nowadays, the method of polymer composite materials is gradually used to replace the traditional method. Among them, Fu Shilan technology system is the most widely used. The superior adhesion and excellent anti-wear and tear resistance of its products ensure that after the repair, the service life of new parts is reached or even exceeded, which greatly reduces downtime.

Butterfly valve installation and maintenance

1. During installation, the valve disc should stop in the closed position.

2. The opening position should be determined according to the rotation angle of the butterfly plate.

3. The butterfly valve with bypass valve should be opened before opening.

4. It should be installed according to the installation instructions of the manufacturer. Heavy-weight butterfly valves should be provided with a solid foundation.

Key points for butterfly valve construction and installation

1. The installation position, height, and import and export directions must meet the design requirements, and the connections should be firm and tight. 2) The handles of all kinds of manual valves installed on insulation pipes must not be downward.

2. The appearance inspection of the valve must be performed before installation. The nameplate of the valve should comply with the current national standard "General Valve Mark" GB 12220. For valves with a working pressure greater than 1.0 MPa and a cut-off function on the main pipe, strength and tight performance tests should be carried out before installation, and only approved after use. In the strength test, the test pressure is 1.5 times the nominal pressure, and the duration is not less than 5min. The valve housing and packing should be qualified without leakage. During the tightness test, the test pressure is 1.1 times the nominal pressure; the test pressure shall meet the requirements of the GB 50243 standard for the duration of the test, and the leakage of the sealing surface of the valve disc is qualified.

Selection points of butterfly valve products

1. The main control parameter of butterfly valve is the size.

2. The butterfly valve is a single-plate type air valve, which has a simple structure, convenient processing, low cost, and easy operation, but has poor adjustment accuracy, and is only suitable for switching or coarse adjustment in ventilation and air conditioning systems.

3. It can be operated by manual, electric or zipper, and can be fixed at any angle within 90 °.

4. Due to the single shaft and single valve plate, the bearing capacity is limited, and the service life of the valve is short under the conditions of large pressure difference and high flow rate. The valve is divided into closed type and ordinary type, and heat insulation and non-insulation.

5. The electric butterfly valve has only two-position control. The electric actuator is the same as the multi-leaf valve.

Butterfly valve installation matters

The butterfly valve is simple in structure, small in size and light in weight, and its component parts are relatively small. Only a few key parts can constitute a butterfly valve, and it is very convenient when it is opened. You only need to select the switch to 90 degrees. The butterfly valve The fluid control is very good. It can increase or decrease the flow rate at any time. The valve has certain resistance when transporting any fluid, and the resistance of the butterfly valve mainly comes from itself, such as the thickness of the butterfly valve body. If you want to reduce the fluid The resistance need only be reduced in thickness.

Elastic seals have the disadvantage of being temperature limited.

The butterfly valve has a wide range of applications. If it is used to control the flow, you need to choose a different type and size of the valve body, because the butterfly valve itself is more suitable for some larger diameter valves when it is designed. Butterfly valves are widely used not only in general industries such as petroleum, gas, chemical, and water treatment, but also in cooling water systems in thermal power stations. ^[3]