Butterfly valve folding common failure

Installation and maintenance
1. During installation, the disc should stop in the closed position.

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

3. Butterfly valve with bypass valve should be opened before opening the bypass valve.

4, should be installed according to the manufacturer's installation instructions, large weight butterfly valve, should be set up a solid foundation.

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

2. The appearance of the valve must be checked before installation, and the nameplate of the valve should comply with the provisions of the current national standard "General Valve Logo" GB 12220. For the working pressure is greater than 1.0MPa and in the main pipe to cut off the role of the valve, should be installed before the strength and strict performance test, qualified after the use. During the strength test, the test pressure is 1.5 times of the nominal pressure, and the duration is not less than 5min. The valve shell and packing shall be qualified without leakage. Tightness test, test pressure is 1.1 times of the nominal pressure; The test pressure shall meet the requirements of GB 50243 standard for the duration of the test, and no leakage of the disc sealing surface shall be considered as qualified.

Key points of product selection
1. The main control parameters of butterfly valve are specifications and sizes.

2, butterfly valve is a single plate type air valve, its structure is simple, convenient processing, low cost, simple operation, but the adjustment accuracy is poor, only suitable for ventilation and air conditioning system as a switch or coarse adjustment of the occasion.

3, can be manual, electric or chain operation, 90° range arbitrary Angle fixed.

4, because of the single shaft single valve plate, bearing force is limited, in the condition of large pressure difference, large flow rate when the valve life is short. The valve has closed and ordinary type, insulation and non insulation.

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

Installation matters
Butterfly valve has simple structure, small volume, light weight, fewer of their component parts, and is the key of a few parts to constitute the butterfly valve, open time is also very convenient, you just need to switch to choose to ninety degrees, the butterfly valve control of the fluid is very good, can increase the flow at any time or reduce flow, the valve when the transportation of any fluid has a certain amount of resistance, 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 resistance to the fluid only need to reduce its thickness.

The elastic seal has the defect that is limited by temperature.

The application range of butterfly valve is also relatively wide, if used to control the flow, you need to choose different types and the size of the body, because the butterfly valve itself is more suitable for some large caliber valve in the design. Butterfly valve is not only widely used in petroleum, gas, chemical, water treatment and other general industries, but also used in the cooling water system of thermal power stations.