M3 M4 M5 M6 Black Hex Socket Head Cap Screw Combined Screw Captive Screws

A screw used for the relative position of a stationary machine. When used, the fastening screw is screwed into the screw hole of the mechanical parts to be fixed, and the end of the screw is pressed on the surface of the other mechanical parts, even if the former piece is fixed on the rear parts. Slotted and hexagon tightening screws are used for parts which are not exposed to the nail head, and the square head fastening screws are suitable for the parts which are allowed to be exposed by the nail head. The clamping force of the screws is the minimum of slotted screws, the largest square head screws, and the hexagon screws are centered. The taper end screws are suitable for the mechanical parts with small strength, and the taper end screws are suitable for the parts of the concave pits on the pressing surface. To increase the capacity of the transfer load, the flat-end screws (the pressure surface should be flat) and the concave end screws, are suitable for the hardness of the larger or often adjust the position of the parts; Long cylindrical end screws apply to tubular shafts (thin-walled pieces, The cylindrical end enters the hole in the tubular shaft to convey a larger load, but it should be used with a device to prevent loose screws.