Butterfly valve daily use failure elimination method

Update:04-06-2020
Summary:Failures and elimination methods of butterfly valves in daily work: 1. Before installation, please confirm whether the ...

Failures and elimination methods of butterfly valves in daily work:

BUTTERFLY VALVE(LEVER) FRPP

1. Before installation, please confirm whether the performance of the product and the direction of the medium flow arrow are consistent with the working conditions, and insert and wash the valve cavity, and there is no foreign matter attached to the sealing ring and the butterfly plate. It must not be closed before cleaning. Butterfly plate, so as not to damage the sealing ring.
2. It is recommended to use the special flange for the disc valve, that is, the HGJ54-91 socket welding steel flange.
3. The position installed in the pipeline, the best position is vertical installation, but not upside down.
4. The flow needs to be adjusted during use, and a worm gear box is used for control.
5. For the disc valve with more opening and closing times, open the worm gear box cover in about two months, check whether the butter is normal, and maintain an appropriate amount of butter.
6. Check the tightness of each connecting part, that is to ensure the bee nature of the filler, and to ensure the flexible rotation of the valve stem.
7. The metal seal butterfly valve product is not suitable for installation at the end of the pipeline. If it must be installed at the end of the pipeline, it needs to be equipped with an outlet flange to prevent the backlog of the seal ring and excessive position.
8. The installation and use of the valve stem regularly checks the valve's use effect, and finds the fault and eliminates it in time.
9. See the table below for details of possible failure elimination methods: common failures and solutions of butterfly valves

Possible failure

1. Debris on the butterfly plate and sealing surface
2. The closing position of the butterfly plate and sealing surface is not correct
3. The flange bolts installed on the outlet side are unevenly stressed or not according to the requirements of Figure 1
4. The pressure test direction is not in accordance with the requirements of Figure 1.

Elimination method

1. Eliminate impurities and clean the inner cavity of the valve
2. Adjust the adjusting screw of the worm gear or electric actuator to achieve the correct valve closing position
3. Check the mounting flange surface and bolt compression country, should be evenly compressed
4. Apply pressure in the direction of the pointed seal

Method for eliminating leakage at both ends of valve

1. The sealing gasket on both sides fails
2. Uneven or non-compact tightening of the pipe flange
3. The upper and lower seal gaskets of the seal ring are invalid

Elimination method

1. Replace the gasket
2. Tighten flange bolts (evenly stressed)
3. Remove the pressure ring of the valve, replace the sealing ring, and invalid gasket

Butterfly valves can be divided into offset plate type, vertical plate type, inclined plate type and lever type according to the structure. According to the sealing form, it can be divided into soft sealing type and hard sealing type. The soft seal type generally uses a rubber ring seal, and the hard seal type usually uses a metal ring seal. According to the connection type, it can be divided into flange connection and wafer connection; according to the transmission mode, it can be divided into manual, gear transmission, pneumatic, hydraulic and electric.