Features of stainless steel drill thread
1. Reference standards: ANSI/ASME B18.6.4, DIN7504.
The most common head types are hexagonal washer head (HW), pan head (P), and flat head (F).
3. The main tooth types are BD tooth and CD tooth. The difference between them is that the tooth type of BD tooth is the tooth type of AB tooth in self-tapping screws, while CD tooth is a mechanical tooth.
4.Length: When the length is within 1-1/2 in, it is a full tooth, and when it is greater than 1-1/2 in, it is a half tooth, and the tooth length is 1-1/2 in.
5. Introduction to BSD and CSD screws:
BSD screws should have different thread lengths and drill bit ends of different shapes. The drill bits are usually No. 2 or No. 3, and their design is adapted to different plate thickness conditions. When the nominal length is equal to or less than 1.50 inches, they are all full-thread screws. The thread space under the head, including the thread end, should be 1 pitch, and if possible, it should be smaller.
(2) CSD screws are machine screw threads with a diameter-pitch combination that approximates a uniform thread and a drill bit end of different shapes, with the end marked as No. 2 or No. 3. Their design is adapted to different plate thickness conditions. CSD screws do not require thread measurement, but should conform to the dimensions specified in the specification. CSD screws are usually used in places where machine screw threads are more advantageous than distance threads. CSD screws with a nominal length equal to or less than 1.50 in. should be full-thread screws, with the thread space below the head, including the thread end, being 1 pitch or less.