Common Classification of Fasteners and Screws

Common classification of fasteners and screws


1. Self-tapping screws

According to the standard, the reference standard for American self-tapping screws is ANSI/ASME B18.6.4, and the metric reference standards are GB845, G8846, JIS B115, JISB1122, JISB, JISB1127, JIS B1125, DIN7971, DIN7972, DIN7973, DIN7981, DIN7982, DIN7983, 1SO1479, 1SO1481, 1SO1482, 1SO1483, 1SO7049(P+), 1SO7050(F+), 1SO7051

Head type:

There are three head types:

The old national standard: round head, countersunk head and semi-sunk head.

The new national standard: pan-head, countersunk head and semi-sunk head, and the British self-tapping nails have various head types.

2. Wallboard nails

Reference standards, JIS B 1125, GB/T 14210-93C and customer specified standards.

Head type: The nail head type of the wall panel currently has a horn head (DW). But there are also large flat head washer (TW) and Warwick head (AF).

Wallboard nails mainly have two types of teeth. For fine and coarse teeth, the pitch and number of teeth are shown in the table below. Fine teeth are divided into double teeth and double teeth, double teeth and single teeth, and high and low teeth. Coarse teeth are single teeth.

Under normal conditions, the angle of Asan is 60°, and the angle of the tail tip is 25°±30°, but some tenants even ask for the angle of Asan to be 45°±50°

3. Tail screw

Reference standard: ANSI/ASME B18.6.4, DIN7504.

At present, the common head types of self-drilling screws are hexagon washer head, pan head and dry head.

The tooth type mainly includes BD tooth and CD tooth. The difference between them is that the tooth type of BD tooth is the tooth type of the AB tooth in the self-tapping screw, and the CD tooth is the mechanical tooth.

Length: When the called length is within 1-1/2in, it is a full tooth, when it is greater than 1-1/2in, it is a half tooth, and the tooth length is 1-12in.

4. Splint nails (fiberboard nails)

Standard: According to customer requirements.

At present, the common ones are flat head, pan head, and big flat head. The trough type is mostly Pozi trough, and quincunx trough.

Tooth type: the ass angle is 40°, one side is 25°, one side is 15°, so that the product has a certain self-locking function, the tail tip angle is 25°±3°, or 24°±3°, generally the tail tip angle of the short specified size is 34°±3°. The bottom of the three splint nails should be relatively smooth without iron filings. Because it is not smooth, it is difficult to screw the product into the hard wood, and there will be broken ends, that is, the screwing test may not meet the requirements, and if there is iron filings, it cannot be plated to the substrate during electroplating. When entering the wood, the iron filings fall off, which makes the substrate easy to corrode, causing the product to rust.

5. Machine screws

Reference standard: Metric system: GB65-85, GB67-85, GB68-85, GB69-85, GB818-85(P+), GB819-85(F+), GB820-85(O+), DIN963-85(F-), DIN964, DIN966-85(O+), JIS1111.96, American system: ANSI/ASME B186.3

Head type: Like self-tapping, there are three types of heads in the new and old international, the old international round head (R) countersunk head (F) and half countersunk head (O).

Tooth type: The tooth type of a machine screw is a mechanical tooth.