The section bending of the elbow is generally carried out by cold section bending. In the case where the factory lacks cold section bending, the hot angle bending is allowed, but the water gas pipe is not hot-bent, and the 20th steel pipe is not suitable for medium frequency bending. Stainless steel tubes and alloy steel tubes should be cold-bent. If hot bending is necessary, stainless steel tubes should be heated to avoid carburization, while alloy steel tubes with a higher tendency to harden should not be watered and cooled. The copper tube should be partially annealed before cold bending.
The profile bending radius of frpp pipe elbow is generally not less than 3 times the diameter of the elbow. In the place where the pipe arrangement is relatively compact, under the premise of ensuring the quality of the elbow, the elbow with less than 3 times the outer diameter of the elbow and a small profile bending radius is allowed. Should be shaped elbows.
Bender operators should be familiar with the structure, performance, and operating procedures and rules of the elbow design. For the cored pipe bending machine, the inner diameter of the elbow and the working part of the plug should be coated with an appropriate amount of lubricating oil. For the cored pipe profile bending machine, the end of the mandrel of the mandrel should be cut beyond the center line of the die perpendicular to it, and the advance value is generally determined according to the test. The new installation and commissioning of the pipe profile bending machine can be selected by reference.