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Failure method of slurry valve

2014-08-08 Number of attention:

Slurry valve is mainly used in aluminium plant. Slurry valve is designed as convex bottom structure and V body according to the actual situation. It also provides two working modes: lifting and lowering. The inner cavity of the valve body is equipped with anti-erosion and anti-corrosion sealing rings. At the moment of opening the valve, the valve body can be protected from being washed and corroded by the medium, and the sealing rings are specially treated to make the surface hardness reach HRC56-62, which has high wear resistance and anti-corrosion function. Disc seals are welded with cemented carbide according to the requirements. Seal pairs are sealed by wire to ensure the reliability of the seal and prevent scarring. Meanwhile, the design of short stroke valve disc is adopted. It is widely used in chemical, petroleum, metallurgy, pharmaceutical, pesticide, dyestuff, food processing and other industries. Various operating modes, such as manual, pneumatic (spring reset, double acting, with and without handwheels), electric, hydraulic, gear, etc.

Failure phenomenon

Reason

Elimination method

The handwheel is not flexible.

1. packing is too tight or packing pressure deflected.

2. there is damage or dirt on the thread of the stem or stem nut.

3. stem bending

4. there is dirt inside the bearing.

1. adjust the nut on the packing pressure plate.

2. remove and repair threads or remove dirt and oil.

3. correct stem or replace stem.

4. dismounting bearings

Leakage at packing site

1. packing is not compressed.

2. packing used too long and damaged.

3. the number of packing rings is not enough.

1. evenly tighten the nuts on the packing plate.

2. replace or increase fillers.

3. adding fillers

Leakage at the sealing surface of disc and valve seat.

1. There is damage on the sealing surface.

2. There is dirt between the sealing surfaces.

1. regrinding the cover

2. clean the sealing surface.

Leakage of connecting body of left and right valve body

1. the nut of the connecting bolt is not only twisted, but also unevenly distributed.

2. There is damage or dirt on the flange sealing surface.

3. Damage of gaskets

1. Tighten the nut evenly.

2. trim the cover or remove the dirt.

3. replace gaskets.