Product introduction
Classification and selection
1、Screw Nomenclature
Surface treatment+grade or material+font+head structure+size
Example: 304 stainless steel cross round head machine screw M5 * 16 nickel plated cross round head three combination screw M4 * 12
2、Typeface
3、Head Type
4、Screw Thread
Regarding tolerances
Nut:measured inner diameter=nominal diameter -pitch±0.2
Machine screw/tightening:measured outer diameter=nominal diameter-0.1~0.2
Fastener product process
Cold heading head type→thread rolling→heat treatment →surface treatment
Standard division
Comparison and difference between pipe thread and cone pipe thread
Pipe threads are mainly used for connecting pipelines,and there are two types:straight pipes and tapered pipes.
The internal and external threads are tightly matched,which can seal oil,water,and gas.
The pipe threads in our country basically followinternational standards and are measured in inches.The standards abroad are divided into 55°and60°.In China,pipe threads are cassified into three types,and somefactories still use this method to mark.
The holes of some pipe joints with G,Z,orZG.
Surface treatment process
Anglo American conversion system
Basic material description
Common standard thread pitch comparison table
Packaging display
