How to choose the material of building fasteners
1. Selection of building fastener materials: The steel pipe uses a 48*3.5mm welded steel pipe, and the strength of the steel used is Q235-A. The surface of the steel pipe should be straight and smooth, without cracks, delamination or hard bending. The newly used steel pipe should have a standard factory certificate. The building fastener must take samples of the incoming steel pipes in the early stage of construction, send them to the relevant national qualifications for verification, and conduct mechanical tests to see whether the steel pipe is resistant to bending and compression. If the test results meet the design requirements, it can be used in construction.
2. The construction of building fasteners uses steel plate fasteners, which should comply with the relevant provisions of the Ministry of Construction's "Standard for Steel Pipe Scaffolding Fasteners" JGJ22-85. The production license of some fasteners is provided by the manufacturer. The specifications of the fasteners should match the steel pipes, the fitting surface should be flat, the movable parts must be flexible, and the minimum distance at the opening of the steel pipe should be no less than 5 mm when clamping. When the bolt tightening torque of the steel pipe reaches 70N.m, it shall not be damaged. If old fasteners are used, the building fasteners must be sampled and sent to a testing unit with relevant national qualifications for anti-slip test. They can be used during construction only if the test results meet the requirements.
3. Before setting up the scaffold, maintenance, rust removal and uniform coloring should be performed, and the color should be beautiful. Paint the vertical poles, guardrails and kicking poles of the building fasteners yellow, paint the scissor braces red, and paint the bottom row of vertical poles and sweeping poles red and white.
4. The scaffolding board used is a bamboo scaffolding board, the thickness of which cannot be less than 50mm, and the spacing of the splicing bolts cannot be greater than 60mm, and the bolt hole diameter and bolts should be tightly combined.
5. The safety net used should be a tight-mesh safety net with a mesh size of 2000 mesh/100cm2 and strong wear resistance. If the weight of a 1.6×1.8m net is above 3 kg, the color of the net should meet the requirements of environmental effects. It is best to choose green and have flame retardancy. The safety net used must have a production license and quality certificate, as well as a permit issued by the construction safety supervision department.
