What should I pay attention to when assembling PVC pipe threaded joints?

Publish Time: 2019-11-01     Origin: Site

The advantages of PVC pipes are extremely obvious, so many PVC pipes are now used. At the same time, there are many threaded joints used in these pipes. PVC threaded couplings provide a reliable, leak-free function. However, sometimes it may leak or break due to improper operation during installation. Therefore, we need to pay attention to some issues that need to be paid attention to during installation.

 

The following are some precautions for PVC joint components:

 

Do not overtighten PVC threaded joints

Use sealant

Use the same type of connector

 

Do not overtighten PVC threaded joints

 

Tighten with your fingers once or twice. each continuous thread has a slightly larger diameter than PVC previous thread on the outer threaded pipe joint. the internal thread gradually becomes smaller. because the thread is tapered, additional rotation can cause the inner thread part to stretch or bear "pull force ". then the threaded joint will split like a wedge driven by a sledgehammer prying the stump open.

 

The strain variable increases as the pipe size decreases. Therefore, smaller diameter threaded joints are more susceptible to cracking than larger threaded joints. Due to the low torque resistance of the small diameter joints, it is also easier to over-torque.

 

Use sealant

 

Do not use Teflon tape, Teflon paste or pipe paint, be sure to use a sealant. Teflon tape, Teflon paste and pipe coatings are suitable for metal pipes and fittings. Metal-to-metal joints are more difficult to tighten than plastic joints; the surface is subject to wear without the aid of lubricants such as Teflon or pipe coatings. PVC joints do not require this lubrication.

 

When the Teflon tape is wrapped around the plastic external thread, strain and tensile stress are increased. The tendency of most installers is to erroneously wrap several layers of tape around the external threads, further increasing stains and stress. Teflon paste and pipe coatings, like Teflon tape, will make the threaded joints smooth. Their use on PVC fittings can cause excessive torque.

 

When using threaded plastic fittings, use a suitable sealant. The correct sealant for threaded joints is non-hardened and compatible with plastics without adding slippage.

 

Non-hardening compounds enter the potential leak point under the action of water pressure, thus achieving a true sealing function. The tape and hardening paste allow a leak path to be formed when the joint is retracted, mechanically bent, or expanded as the temperature increases. The sealant must be compatible with the plastic. Many brands of pipe sealants contain oils, solvents or carriers that can damage plastics. The manufacturer must demonstrate that the proper sealant is not harmful to the joint material and will not contaminate the liquid in the pipeline.

 

Use the same type of connector

 

Do not use the Schedule 80 threaded connector in the Schedule 40 system. Use the same threaded fittings in the same piping and fittings.

 

Many plastic pipe system installers have problems with disassembly, and they believe that the accessories for the 40th plan are weak. Their conclusion is that the problem can be solved by switching to the "more powerful" timetable 80 accessories.

 

 

PVC pipe threaded joints are often used in pipes, and they are very useful, but if they are improperly installed, they are meaningless. So be sure to pay attention to these problems when installing, otherwise it will cause a lot of problems will be very annoying.

 

If you have any questions about PVC couplings, feel free to contact us and we will answer them for you. If you need to buy, I believe that we are professional enough here, you need the service I have here.


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