The use of fasteners should pay attention to details, performance is very important, regular maintenance is the focus, to ensure the normal operation of the machine.In order to prevent some problems with fasteners, the following points must be paid attention to during the daily maintenance of fasteners.
XNUMX. Pollution generated during rinsing.
Fasteners need to be cleaned with silicate cleaning agent after quenching, and then rinsed, so be very careful when rinsing to prevent residues.
XNUMX. Unreasonable stacking of fasteners.
The fasteners will show signs of discoloration after tempering, and there may be oily residues after soaking in ether, indicating that the surface of the fasteners is not clean.After analysis, it is indicated that the fasteners are stacked unreasonably when heated, which leads to slight oxidation of the fasteners in the quenching oil.
XNUMX. Surface residues.
There is a white residue on the high-strength screw, which was confirmed to be phosphide after analysis with an instrument.This reaction was caused because the acid washer was not cleaned and the rinsing tank was not thoroughly inspected.
Fourth, alkali burns.
High-strength screws are blackened by quenching heat and have a uniform and smooth oil-black outer surface.After testing, it was caused by alkali burns.Therefore, in steel fasteners, the surface alkalis cannot be removed in the quenching oil, so that the surface burns at high temperatures and aggravates the damage during tempering.It is recommended to thoroughly clean and rinse the fasteners before heat treatment to completely remove the alkaline residues that cause the fasteners to burn.
XNUMX. Improper rinsing.
For large-size fasteners, polymer aqueous solutions are often used for quenching. Before quenching, they are cleaned and rinsed with an alkaline cleaning machine. After quenching, the fasteners have rusted on the inside.Therefore, the rinsing water should be changed frequently to ensure that the fasteners will not rust during rinsing.
XNUMX. Excessive corrosion.
High-strength fasteners often see some black streaks. The black streaks are the contaminants of the surface residues and the quenching oil that has been dried. It is the evolution of the gas phase during the quenching process.Because the quenching oil is excessively aged, it is recommended to add new oil.