Making elbow using elbow machine and benefits

Making elbow using elbow machine and benefits  

Push elbow technology adopts special elbow pusher, core die and heating device, so that the blank on the die moves forward under the push rod, heating, expanding and bending.  This process.  The deformation characteristics of hot-push bend tube are determined by the volume variation of metal material before and after plastic deformation.  The diameter of the tube blank is smaller than the diameter of the elbow, and the inner arc is compressed during the deformation of the blank controlled by the core mold.  The flow of the metal compensates for the thinning of other parts due to diameter expansion, resulting in an elbow with uniform wall thickness.

Hot pushing elbow is on the basis of metal composite materials about volume will not change before and after plastic deformation regularity of pipe diameter, chooses the pipe diameter less than bend diameter, according to the hollow floor in control of the whole deformation process, the embryo is making inner arc shrinking liquidity metal materials, compensation to thinning by expanding the other location,  Thus, the elbow with beautiful appearance design, well-proportioned wall thickness and can continue to work is very suitable for mass production, so it becomes the key forming way of carbon steel elbow and alloy steel elbow, and is also used in the forming of some specifications and models of stainless steel elbow.

At the end of 1980s, I was exposed to the process of pushing steel elbow by mechanical + mould inner tube + medium frequency heating method, but later it was probably difficult to control the thickness of inner and outer side wall, so it was seldom used in practice.

The main parameters of the push elbow geometry are radius of curvature R, section irroundness perpendicular to the circle of radius of curvature (actual section diameter Ds - standard section diameter Db) and wall thickness δ.  The process parameters affecting the geometry of push elbow include the material of push blank, wall thickness and outer diameter, material and shape of mandrel head, heating temperature and its distribution, and propulsion speed.  Thermal power industry commonly used push elbow materials are WB36 and A335P22.  The material and shape of mandrel head is an important technological parameter, which is directly controlled by design and manufacture.