Forming Process of Prestressed Metal Bellows

Publish Time:2017/06/13 04:18 Author:admin Views:50 Origin:Site

Prestressed metal bellows is a complex shape, high performance requirements of a thin shell components. It has many manufacturing processes and complicated processes. Therefore, in the manufacture of bellows, the correct process design and implementation is essential.

Prestressed metal tube manufacturing process
Prestressed metal bellows tube is divided into two kinds of seamless tube and seamless tube.
Seamless tube billet manufacturing, according to different raw materials. Using different methods of manufacturing. Material plus the factory can provide wall thickness 0.1 ~ 0.3mm, diameter φ10 ~ 60mm long stainless steel thin-walled seamless tube. This seamless tube table and high finish, but the wall thickness tolerance (+/- 0.03mm), generally used to manufacture spiral corrugated pipe and the performance requirements of the ring bellows is not high. Metal bellows production plant can be used 0.8 ~ 1mm thick metal plate (with) material or wall thickness of 0.5 ~ 1mm standard thin-walled tube, after a number of drawing or spinning drawing process to produce a variety of corrugated pipe billet. This process can be used to produce high thickness, wall thickness tolerance (<= + / - 0.005mm), the length of the tube, for the manufacture of higher requirements of prestressed metal bellows.
The manufacture of slit tubes is generally made of the required thickness of the plate or strip, reel after the use of special welding butt welding. The quality of the seam is directly dependent on the quality of the board (belt) and the quality of the weld. In general, its wall thickness tolerance is easier to control.
1. Many times thinning and drawing process
Many thinning and deep drawing process is suitable for the manufacture of corrugated pipe billet with length less than 300mm. The process mainly includes blanking, multiple drawing, multiple heat treatment and multiple thinning and drawing.
2. Steel ball spinning thinning stretch manufacturing process and equipment
Steel ball spinning thinning deep drawing, is the rough in the high-speed rotation, by the punch, die and steel rolling between the rolling and thinning of a process. The high speed rotation of the punch (or die) causes the steel ball itself to rotate and rotate at high speed along the blank cycle. When the blank is subjected to axial feed on the punch, the material is subjected to positive force and tangential force Deformation.
3. Manufacturing process of welded tube
The use of welding method to produce bellows tube, is a high production efficiency, low cost, easy to control the wall thickness and adaptability of the process. Currently used for the manufacture of expansion joints with large diameter corrugated tube and the manufacture of hose tube. Corrugated tube tube welding, the current use of the main gas shielded DC argon arc welding, micro-arc plasma welding and laser welding process. Welding thickness of 0.1mm ~ 1mm, the material is 1Cr18Ni9Ti, 0Cr18Ni9, 00Cr17Ni14Mo2 and GH169 and so on.
4. Manufacture of multi-layer bellows tube
Multi-layer bellows has a high resistance to pressure, but also has a small stiffness and a large displacement, commonly used to make metal expansion joints and no leakage valve with bellows.
Expansion joints with multi-layer bellows, the diameter is generally more than φ80mm, and its tube is mostly in the welding tube billet, set aside the casing gap, respectively, the corresponding layer of the tube after the tube can be followed.
Valve with multi-layer bellows most of the inner diameter is less than φ60mm, the multi-layer tube bad, there are different manufacturing methods. One is according to the reserved casing gap, with the rolling or spinning process were to create the corresponding tube, the order of casing into a multi-layer tube. Another method is to use a basic tube, and then use the diameter reduction or expansion process, into the corresponding layer of the tube and then the order of casing into a multi-layer tube. As this modification is more accurate than the rolling, the diameter of the spinning pipe diameter is low, so the spacing of the reserved casing is slightly larger.
Multi-layer tube billet, in accordance with the bellows products on the inter-layer quality requirements are different, can be used under the hard casing and soft under the casing two methods. After the finished hard tube, clean the inner and outer surfaces, direct casing, and then solid solution or annealing heat treatment. This method because after the casing to go through the heat treatment and pickling and other processes, it is difficult to ensure that the inter-layer surface smooth and no extra layer between the layers, hard tube before the first heat treatment and pickling, in the smooth surface quality, and then soft State of the casing, can make the quality of the corrugated pipe products to be a reliable guarantee.