At present, there are two kinds of fasteners used in China: malleable cast iron fasteners and steel plate pressed fasteners. Due to the mature manufacturing technology of malleable casting fasteners, there are national product standards and professional testing units, and the quality is easy to guarantee.
Malleable casting fasteners should generally be made of malleable cast iron with mechanical properties not lower than KTH 330-08. Castings shall be free from cracks, blowholes, shrinkage cavities, sand holes or other casting defects that affect the use. Sticking sand, riser residue, caulking, wool and scale that affect the appearance quality shall be removed.
The joint surface of fastener and steel pipe should be strictly shaped to ensure good contact with steel pipe. When the fastener clamps the steel pipe, the minimum distance at the opening should not be less than 5 mm The movable part of the fastener should make it rotate flexibly, and the gap between the two rotating surfaces of the rotating fastener should be less than1mm.
Extended data
operating characteristic
1, excellent fracture resistance-all steel cold pressing
Advanced structure, all steel plates are formed by cold pressing, and the strength and toughness exceed national and international standards, completely eliminating the hidden danger of scaffolding collapse caused by the fracture of old cast iron fasteners.
2. Excellent skid resistance-large bonding area
Ensure that the steel pipe and the fastener are in the state of surface joint with the largest joint area, overcome the point or line joint between the old fastener and the steel pipe, and eliminate the hidden danger of steel pipe sliding, thus ensuring and improving the overall mechanical properties and safety performance of the scaffold.
3. Strength resistance-new connection
It ensures that the fastener can always be fixed vertically, correctly and firmly under the condition of steel pipe displacement, and eliminates the possibility of steel pipe slippage.
4. Strong rust prevention-passivation treatment
The whole piece has been passivated and galvanized to prevent corrosion, and its corrosion resistance has been greatly improved, and its service life is far longer than that of old fasteners.
5, fast and portable-structural optimization
Fasteners are light and beautiful, with faster loading and unloading speed and lower labor intensity.
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