PVC Bending-Heating

[manuel bonilla]

Is the use of heat for the purpose of bending a PVC pipe a correct procedure?

If it is, besides keeping the cross section intact, what would be other cares that need to be taken?

This is a widespread pactice in Costa Rica, but I really feel unsure if it should be done or how to do it properly.

 

[charlie]

Re: PVC Bending-Heating

Using heat is the only way I know of bending PVC. However, it is wise to follow the manufacturer's directions. That would require a heating box and plugs in order to heat the conduit evenly and at the correct temperature. The plugs will keep the inside diameter almost round at the bends.

I used to use a torch and the exhaust from the truck. Neither way is acceptable by the NEC, the manufacturer's instructions, or common sense. You will end up with a sloppy job and damaged conduit.

 

[sjaniga]

Re: PVC Bending-Heating

We use the Greenlee heat blankets and plugs, just be sure not to superheat the PVC, it will brown quickly, also, use a wet rag when you have the bend the way you want it, this will cool it and lock it in faster.

 

[goldstar]

Re: PVC Bending-Heating

Another good tip is to keep a spray bottle handy (like an empty Windex bottle) and a pair of work gloves (the PVC gets real hot to handle). Fill the bottle with cold water before you start heating your PVC and keep it close to where you're making the bend. Once you form the bend, spray water onto the bend and it will set up exactly as you want it to.

If you're using the Greenlee box heater and you keep your gloves and bottle inside the box during storage, don't forget to remove it before you turn on the heater. So far I've burnt up 2 pairs of gloves and 2 bottles !!!

[ July 03, 2003, 05:58 AM: Message edited by: goldstar ]

 

[bennie]

Re: PVC Bending-Heating

I like that spray bottle cooler, welding gloves also work good for handling the conduit.

 

[hbiss]

Re: PVC Bending-Heating

With large diameters like 4in you might want to use compressed air to pressurize the conduit while bending to maintain the dimensions. Those plugs have stems that can be fitted with an air fitting. All you need is a few PSI so a bicycle pump or a portable "flat tank" with a regulator work well.