Annealing process for high-strength hardware bolts

Abstract

The invention discloses an annealing process for high-strength hardware bolts. The multiple hardware bolts are put into a high-temperature furnace for preheating treatment at first, and the preheatingtemperature is 120-160 DEG C; then the temperature inside the high-temperature furnace is controlled with the heating speed of 50-90 DEG C / h to conduct heating for 1-2 hours and then stop heating, cooling with the furnace is conducted for 10-15 min, heating is conducted for 1-2 hours with the heating speed of 50-90 DEG C / h, cooling with the furnace is conducted for 15-20 min, then heating is conducted with the heating speed of 100-120 DEG C / h till the temperature is 680-720 DEG C finally, and heat preservation is conducted for 2-3 hours; and cooling with the furnace is conducted for 1.5-2.5 hours, then the temperature inside the high-temperature furnace is controlled with the cooling speed of 10-30 DEG C / h to conduct cooling for 20-40 min, cooling with the furnace is conducted till the temperature is below 540-560 DEG C, and then the high-temperature furnace is opened and naturally cooled to the room temperature. In this way, the annealing quality can be greatly improved, the machining difficulty is reduced for the subsequent process, and the strength performance of the hardware bolts is further ensured.

Description

technical field

[0001] The invention relates to the field of hardware accessories, in particular to an annealing process for high-strength hardware bolts. Background technique

[0002] Hardware spare parts refer to machine parts or components made of hardware, as well as some small hardware products. They can be used alone or as auxiliary tools. Among them, hardware bolts are one of the typical representatives of hardware spare parts. The physical properties of bolts on the market It is difficult to make a breakthrough in terms of performance. If the material of the bolt is adjusted, the production cost will be greatly increased. However, the annealing process for hardware bolts is relatively traditional and the method is single. Therefore, it is currently necessary to improve the annealing process of hardware bolts to achieve traditional A breakthrough in the physical properties of bolts. Contents of the invention

[0003] The technical problem mainly solved by the prese...