pan head self tapping screws material, heat treatment, surface treatment
Pan head self tapping screws can generally be made of stainless steel, carbon steel, titanium, aluminum, copper, brass. The most frequently used materials are carbon steel and stainless steel.
Carbon steel pan head tapping screws are made of low carbon steel and have sufficient hardness for cutting or forming internal threads after heat treatment and surface hardening. Stainless steel self-tapping screws are generally made of 304HC, and some are made of 201, 316 stainless steel. Generally, the hardness required for cutting can be obtained after head and rolling thread.
For carbon steel pan head self tapping screws, the relationship between carburized depth, surface hardness, and core hardness is critical. If the carburized layer is too thin, the screwing effect of the screw is poor; if it is too thick, it will adversely affect its torsional strength and the toughness of the screw.
The surface treatment of most carbon pan head self tapping screws is galvanized and nickel-plated. Stainless steel and copper self-tapping screws are generally cleaned and degreased. The surface treatment of titanium and aluminum self-tapping screws is anodized, natural cleaning and degreasing. When there is a requirement for the strength of carbon steel self-tapping screws, attention should be paid to the problem of hydrogen embrittlement.
When the pan head self tapping screws is electroplated, it is necessary to pay attention to the thickness of the plating layer. The coating not only increases the size, but also the different plating materials affect the screwing and tightening torque of the screw. Because the aperture is very sensitive to normal screwing in and tightening. Therefore, the correct aperture size should be determined by experimentation. And the thickness of the coating used for the test should be consistent with the thickness of the actual plating, so as not to cause a deviation.
Carbon steel pan head tapping screws are made of low carbon steel and have sufficient hardness for cutting or forming internal threads after heat treatment and surface hardening. Stainless steel self-tapping screws are generally made of 304HC, and some are made of 201, 316 stainless steel. Generally, the hardness required for cutting can be obtained after head and rolling thread.
For carbon steel pan head self tapping screws, the relationship between carburized depth, surface hardness, and core hardness is critical. If the carburized layer is too thin, the screwing effect of the screw is poor; if it is too thick, it will adversely affect its torsional strength and the toughness of the screw.
The surface treatment of most carbon pan head self tapping screws is galvanized and nickel-plated. Stainless steel and copper self-tapping screws are generally cleaned and degreased. The surface treatment of titanium and aluminum self-tapping screws is anodized, natural cleaning and degreasing. When there is a requirement for the strength of carbon steel self-tapping screws, attention should be paid to the problem of hydrogen embrittlement.
When the pan head self tapping screws is electroplated, it is necessary to pay attention to the thickness of the plating layer. The coating not only increases the size, but also the different plating materials affect the screwing and tightening torque of the screw. Because the aperture is very sensitive to normal screwing in and tightening. Therefore, the correct aperture size should be determined by experimentation. And the thickness of the coating used for the test should be consistent with the thickness of the actual plating, so as not to cause a deviation.
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