Installation and maintenance of butterfly valves to troubleshoot

Common malfunctions

The rubber elastomer in the butterfly valve will tear, wear, age, perforate or even fall off during continuous use. However, the traditional thermal vulcanization process is difficult to meet the needs of on-site repair. Special equipment must be used for repair, which consumes a lot of heat and electricity, which is time-consuming and labor-intensive. Nowadays, polymer composite materials are gradually used to replace traditional methods, among which the most widely used is the Fuschlan technology system. The superior adhesion and excellent anti-wear and tear-resistant properties of its products ensure that the service life of the new component is reached or exceeded after repair, and the downtime is greatly reduced.

Installation and maintenance

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

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

3. For the butterfly valve with bypass valve, the bypass valve should be opened before opening.

4. The installation should be carried out according to the installation instructions of the manufacturer, and the heavy-weight butterfly valve should be installed with a firm foundation.

Construction and installation points

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

2. The valve must be visually inspected before installation. The nameplate of the valve should comply with the current national standard "General Valve Marking" GB 12220. For valves with a working pressure greater than 1.0 MPa and a cut-off function on the main pipe, the strength and tightness performance test shall be carried out before installation, and the valve shall be used only after it is qualified. During 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 should meet the requirements of the GB 50243 standard during the test duration, and no leakage on the valve flap sealing surface is qualified.

Product selection points

1. The main control parameters of the butterfly valve are specifications and dimensions.

2. The butterfly valve is a single-plate air valve with simple structure, convenient processing, low cost, simple operation, but poor adjustment accuracy. It is only suitable for switching or rough adjustment occasions in the ventilation and air-conditioning system.

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

4. Due to the single-axis 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 large flow rate. The valve is divided into closed type and ordinary type, heat preservation and non-heat preservation.

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

Installation matters

The butterfly valve is simple in structure, small in size, light in weight, and its components are relatively small. A few key parts can constitute a butterfly valve. It is also very convenient to open. You only need to select the switch to ninety degrees. The butterfly valve The control of the fluid is very good. The flow can be increased or reduced at any time. The valve has a certain resistance when transporting any fluid. The resistance of the butterfly valve mainly comes from its own, such as the thickness of the butterfly valve body. If you want to reduce the fluid The resistance only needs to reduce its thickness.

Elastic seal has the defect of being limited by temperature.

The application range of the butterfly valve is also relatively wide. If it is used to control the flow, it is necessary to choose different types and valve body sizes, because the butterfly valve itself is more suitable for some larger diameter valves when it is designed. Butterfly valves are not only widely used in general industries such as petroleum, gas, chemical, and water treatment, but also used in cooling water systems of thermal power stations.