(1) Attention shall be paid to the placement of workpieces to ensure uniform heating and prevent overheating. When using gas furnace or natural gas furnace, pay attention not to make nozzle or flame directly heat the workpiece.
(2) For shaft and slender rod workpieces, pay attention to the placement of workpieces to prevent deformation.
(3) When fully annealed and charged, generally small and medium-sized carbon steel and low-alloy steel workpieces can be directly loaded into the furnace that has been heated to the annealing temperature without controlling the heating speed; they can also be charged at low temperature and heated with the furnace. For large parts with medium or high alloy or complex shape, the furnace shall be installed at low temperature, the temperature shall be raised in sections, and the heating rate shall not exceed 100 ℃ / h.
(4) For the stress relief annealing of large workpieces, the furnace shall be installed at low temperature, and the temperature shall be raised slowly to prevent the thermal stress due to too fast heating.
(5) Normalizing air cooling shall be placed on the flat ground as far as possible; no matter what kind of workpiece, it shall be opened up and placed in the dry place for air cooling during air cooling, and shall not be stacked or overlapped, and shall not be placed in the wet place or the place with water, so as to ensure uniform cooling speed and uniform hardness.
(6) Workpieces with different materials but the same heating temperature can be heated in the same furnace.
(7) For workpieces with different section sizes, when heating in the same furnace, small pieces shall be placed at the outer end of the furnace.
(8) Generally, the water temperature shall not exceed 40 ℃, and the oil temperature shall not exceed 80 ℃
On 2018-08-08 11:45:46
