What are the problems with PVC pipe fittings and how to deal with

What are the problems with PVC pipe fittings and how to deal with

The advantage of PVC pipe fittings is that it has been popular over the years and is used in many places. PVC pipe fittings can be used in drainage, food, chemicals, mud, heating and cooling, wastewater, ultrapure liquids, gases, compressed air and vacuum systems. When PVC pipe fittings are produced, there are some problems due to mass production. Therefore, everyone must pay attention when using them. But pay attention to the problem? How should these problems be solved? Next we will analyze these problems and solve them.

A list of this article:

What problems can the pipe fittings have?

How to solve these problems?


What problems can the pipe fittings have?

(1) There are black decomposition lines in PVC pipe fittings

(2) Discoloration of the pipe or occurrence of burnt area

(3) Peeling on the surface of the pipe

(4) Pipe warpage deformation

(5) The surface of the pipe is rough and dull

How to solve these problems?

1. There are black decomposition lines in PVC pipe fittings.

1) The injection temperature is too high. When the black line is not serious, the temperature can be lowered. If it is serious, it must be stopped for cleaning.

2) The round gate is too small. Improve the gate.

3) The mold is poorly vented. Trim the mold to improve the exhaust.

2. The pipe is discolored or burnt

1) Temperature control fails and local overheating occurs. Replace the malfunctioning temperature control device.

2) The material temperature is too high. Reduce the temperature of the fuselage, screw speed, reduce back pressure and other means to reduce the material temperature.

3) There is stock in the fuselage of the fuselage. Clean the barrel and screw.

3. Peeling on the surface of the pipe

1) Excessive lubricant in the formulation. Reduce the amount of lubricant used.

2) Insufficient injection volume. Increase the amount of feed.

3) The gate is too small and generates too much frictional heat. Modify the mold and properly enlarge the gate.

4) The holding time is too short. Extend the holding time.

5) The mold and insert temperature is too high. Properly reduce mold and insert temperatures.

4. Pipe warping deformation

1) Insufficient set time. Increase clamping and cooling time.

2) The wall thickness of the pipe is not uniform. Reduce the mold temperature of the thick-walled part, reduce the injection pressure and the pressure holding pressure.

3) The ejector lever is not in the proper position. Modify the mold.

5. The surface of the pipe is rough and dull


1) The temperature is too low and the material flow is poor. Appropriately increase the barrel temperature of the injection molding machine.

2) Too much material is added. Properly reduce the proportion of return.

3) The mold is rough and the temperature is low. Trim the mold to increase the temperature.

4) Low injection pressure and slow speed. Increase filling speed and pressure.

5) The pipe with thicker walls is not sufficiently cooled. After demolding, the tube was placed in cold water for further cooling.


PVC pipe fittings have been very popular in recent years, and of course everyone must be very interested in it. Its price is not high and it can be used for a long time. However, various problems arise when producing accessories. How can these problems be solved? I hope this article can help you. If you encounter problems, you don’t need to panic. You can find a professional plumber to carry out maintenance. If you have any questions about PVC pipe fittings, you can consult us.

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