1. Thermal expansion
seamless pipe 16Mn material after straightening head and tail were cut early, simply cut necking and space segments and pulling the tail section cracked, no more cut; the end face to ensure smooth, not skewed;
2. Finishing classes at the test bench to be treated pipe expansion material 16Mn seamless surface inspection, the outer folding, inner folding, crack, less the number of external scarring and shallow depth of grinding to clean, as compared with outer flap multiple or deep grinding can not directly sentenced to waste, can not be used diffuser material; grinding the rear wall thickness than the negative deviation and fill with welding Shuhei;
3. Thermal expansion operatives came to power after the tubing rack, check 16Mn seamless tube inner and outer surfaces, found missed outside off, cracks and other defects with the grinding wheel clean, depending on the grinding depth with welded wire reinforcing and Shuhei ;
4. The tube wall thickness and material support by length measurement and make a record, according to the specifications 16Mn seamless tube wall thickness and length selection system expansion specification (φ273,325,377,426), to ensure that the finished product after the head and tail cut lengths not less than 6 m
5. Encountered stiff head tube to be marked in a stiff head parts, pipe expansion process, the stiff head when approaching the site to slow forward speed, an increase in temperature;
6. After completion of the pipe expansion of the inner and outer surfaces to be checked, not to eliminate defects marked on 16Mn seamless and recorded in production records; capable of grinding to go clean after grinding annealing furnace;
7. The thermal expansion of working class before the start of expanding the system to measure the thickness of the material before the three pipe, 16Mn seamless expansion of the system and then measure the wall thickness, wall thickness adjusted according to changes in velocity and temperature expansion of the system;
8. To 16Mn thermal expansion of two flat, not allowed to be expanded to the level when the system seamless docking;
9. After each expansion after a 16Mn seamless tube wall thickness to be measured after the expansion, according to standards and specifications determined to do production records.
