This standard specifies the classification, technical requirements, test methods, inspection rules, signs, packaging, transportation and storage of steel pipe scaffold fasteners. This standard applies to fasteners made of malleable cast iron or cast steel used in construction projects, such as steel pipe scaffolding, derrick, and formwork supports with an outer diameter of 48mm. It is also suitable for fasteners required in municipal, water conservancy, chemical, metallurgical, coal and shipbuilding projects. Fasteners with a steel pipe outer diameter of 51 mm can also be implemented with reference to this standard.