Screw nuts are not unfamiliar to product designers. In […]
Screw nuts are not unfamiliar to product designers. In fact, from the beginning of the sensible screw has a preliminary understanding of everyday life can be seen everywhere, from housing decoration, small to computer mobile phones. But when we develop new products, there is always a kind of inexplicable embarrassment that we can't find, such as the size and thickness of the nut, the length of the screw, and the screw with special requirements.
Next, I will summarize the specifications and models of the nuts and screws that we often use in the structure of electronic products, so that we can find them better in the follow-up work.
01, screw production standard
GB - China National Standard (GB) ANSI - American National Standard (US Standard)
DIN-German National Standard (German Standard) ASME-American Association of Mechanical Engineers Standard
JIS-Japanese National Standard (Japanese Standard) BSW-British National Standard
GB - national standard is one of many standards in our country. In addition, there are industry standards, professional standards and some standards. National standards are divided into: GB (compulsory standard), GB/T (recommended standard) and GBn (national internal standard). What we usually see, like GB30, GB5783 and so on, are mandatory standards.
In addition to some basic sizes such as head-to-side, head thickness and so on, the main difference among the above standards is the threaded part. The threads of GB, DIN, JIS and so on are all in MM (millimeter) units, collectively known as metric threads.
Common screw classifications are as follows:
PA--round head pin screw
PB-round head flat foot screw
PT--round head pin screw
BA-Big Head Toe Screw
BT--Flat-footed Medium-foot Screw
KA-Flat-Headed Toe Screw
KB-Flat Head Flat Foot Screw
KT-Flat Head Interpodal Screw
PWA/WA--With Meson Pin Screw
PWB/WB--Flat Foot Screw with Meson
PWT/WT--Mesopin Screw with Meson
PM--Tooth Screw for Round Head Machine
KM-Flat Head Flat Foot Machine Tooth Screw
Hexagonal machine tooth screw
Code description: A-pointed feet; B-big head, flat feet; M-machine teeth; K-flat head; P-round head; T-intermediate feet; W-banded meson.