Bending Spring is a metallic, flexible spring used to bend PVC Conduit Pipes by providing them a stable internal structure needed to achieve a neat, distortion-free bend.
One of the ends of the bending spring is tapered, while the other has a ring end. The ring end is tied with a string to pull the spring out when the pipe gets bent. They are available in different sizes, e.g. 20 mm, 25 mm for different PVC pipe sizes.
Only good quality PVC Conduit Pipes can withstand the pressure required by the spring bending, while poor quality PVC Conduit Pipes will warp when pressure is applied. Pressfit manufactures three types of Bending Springs, namely: LMS Bending Spring, MMS Bending Spring, HMS Bending Spring in various different sizes.
During wiring installations, bends can be created directly with PVC bends. However, it is not a best practice as you will have to go through the hassle of applying PVC cement to the joints. Manual bends with bending spring give you a bump-free, smooth surface that is very helpful in pulling wires out during the wiring process.
Making them is very simple. Firstly, you need to mark the area where you want to create the bend. Insert the bending spring into the passage with the marked area as the center. Make sure you have a string tied with the ring end to make it easy to pull out the spring when the pipe gets bent.
You can soften the pipe by warming it with your hands or some other material. Hold the pipe where the marked area is at equal length with the hands. Now start bending the pipe, you can take the support of your thigh, knee, etc. Finally, when you get the angle you want for the bend, pull out the bending spring.