Butterfly valve is a kind of valve which uses circular butterfly plate as opening and closing parts and rotates with the stem to open, close and adjust the fluid passage. The butterfly plate of the butterfly valve is installed in the diameter direction of the pipeline. In the cylindrical channel of the butterfly valve body, the disc butterfly plate rotates around the axis, and the rotation angle is between 0 ~90. When the rotation angle is between 0 ~90, the valve is fully open.

Key Points of Construction and Installation

1) Installation location, height, import and export direction must meet the design requirements, the connection should be firm and tight.

2) All kinds of manual valves installed on the insulation pipeline shall not have downward handles.

3) Appearance inspection must be carried out before the valve is installed. The nameplate of the valve should conform to the current national standard "General Valve Mark" GB 12220. For valves with working pressure greater than 1.0 MPa and cutting off effect on main pipe, strength and tightness test should be carried out before installation, and the valves can be used only after they are qualified. In the strength test, the test pressure is 1.5 times of the nominal pressure, and the duration is not less than 5 minutes. The valve shell and packing should be qualified without leakage. The test pressure is 1.1 times of the nominal pressure in the tightness test, and the test pressure should meet the requirements of GB 50243 standard for the duration of the test, with no leakage on the valve sealing surface as the qualification.

I. Key Points of Product Selection

1. The main control parameters of butterfly valves are specifications and sizes.

2. The butterfly valve is a single-plate air valve, which has simple structure, convenient processing, low cost and easy operation, but its adjustment accuracy is poor. It is only suitable for the occasion of switch or rough adjustment in the ventilation and air conditioning system.

3. It can be operated manually, electrically or zipper, and fixed at any angle in the range of 90 degrees.

4. Because of the limited bearing capacity of the single-axis single valve plate, the service life of the valve is short under the conditions of high pressure difference and high flow rate. The valve can be 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.