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Mandrel is used for assembling with other parts, so that the mandrel must with certain matching precision and surface contact strength as well as enough stiffness and abrasion resistance to meet operating requirements. Hydraulic pipe bending mandrel is one of the key parts of pipe bending machine, it is for purpose of preventing pipe inner wall form wrinkling and controlling ovality during cold bending process of pipe bending machine.
The outside pipe wall at the bend position will produce tensile stress, and the inside of the pipe wall will produce compressive stress。The permanent deformation can be obtained if there is enough force to make the outer steel plate reaches its offset limit. If the inner pipe wall at the bend position has been pressed, the pipe wall will wrinkle or crease. Intentionally and unintentionally cause wrinkles in the oil and gas pipes are not allowed.
In general, the hydraulic pipe bending mandrel made with bad material will be broken. The main problem that caused mandrel broken is its materials, as well as the thickness and size of the pipe, design of the mandrel and the bending machine itself.
The hydraulic pipe bending mandrel we produce with wedge-form force transmission mechanism: powerful and reasonable distributed clamping force, intense self-locking function; Clamping cylinder inside placed: compact and reasonable structure, powerful clamping force; Hydraulic motor travelling setting: this setting is for walking function realization, working position can be controlled precisely by the control system; Scale polyurethane clamping shoes: reasonable design, easy for assembling and disassembling, high abrasive resistance. Our mandrel never fractured during construction process.