1. Traditional fastener-type steel pipe scaffolding is used, with steel pipes and right-angle, turning, and butt-joint fasteners. The extension of the scaffolding uprights must be done using butt-joint fasteners. The ground bracing, horizontal tie rods, and scissor bracing of the scaffolding are all made of steel pipes, and their extensions are all fixed with lap fasteners. The lap length is not less than 1m, and three fasteners are used. Considering the mature construction technology of fastener-type steel pipe scaffolding and the familiarity of the operators with this technology, the horizontal pipes of the beam and slab bottom formwork are directly fixed to the scaffolding uprights.
2. Scaffolding material acceptance
(1) The steel should comply with the current national standards “Carbon Structural Steel” GB/T 700 and “Low Alloy High Strength Structural Steel” GB/T 1591.
(2) The steel pipes shall meet the requirements for Q235 ordinary steel pipes specified in the current national standards GB/T 13793 “Straight Seam Electric Welded Steel Pipes” or GB/T 3092 “Welded Steel Pipes for Low-Pressure Fluid Transportation,” and shall also meet the requirements for Q235A grade steel in the current national standard GB/T 700 “Carbon Structural Steel.” Steel pipes with severe corrosion, bending, flattening, or cracks shall not be used.
(3) The maximum weight of each steel pipe shall not exceed 25 kg, and Ф48×3.0 steel pipes shall be used.
(4) The dimensions and surface quality of the steel pipes shall meet the following requirements:
a) A product quality certificate shall be provided;
b) A quality inspection report shall be provided, and the steel pipe material inspection method shall comply with the relevant provisions of the current national standard “Metallic Materials – Tensile Testing Method” GB/T 228.
c) The surface of the steel pipe shall be straight and smooth, and shall not have cracks, scars, delamination, misalignment, hard bends, burrs, indentations, or deep scratches;
d) Deviations in the outer diameter, wall thickness, cross-section, etc., of the steel pipes shall comply with the provisions of the current standard “Safety Technical Specification for Construction Coupler-Type Steel Pipe Scaffolding” JGJ130-2011;
e) The steel pipes must be coated with anti-rust paint.
(5) The inspection of old steel pipes shall comply with the requirements for new steel pipes and shall also meet the following requirements:
a) The surface rust depth shall comply with the provisions of the current standard “Safety Technical Specification for Construction Coupler-Type Steel Pipe Scaffolding” JGJ130-2011. Rust inspection shall be conducted annually. During inspection, three severely rusted steel pipes should be randomly selected. A transverse section should be cut and sampled from each severely rusted section for inspection. Pipes with rust depth exceeding the specified value must not be used.
b) The bending deformation of the steel pipes should comply with the current standard “Safety Technical Specification for Steel Pipe Scaffolding with Couplers in Building Construction” JGJ 130-2011.
c) Drilling holes in the steel pipes is strictly prohibited.
(6) Steel castings should meet the requirements of ZG 200-420, ZG 230-450, ZG 270-500, and ZG 310-570 steel as specified in the current national standard “Cast Carbon Steel Parts for General Engineering” GB/T 11352.
(7) The steel pipe couplers for the scaffolding should comply with the current national standard “Steel Pipe Scaffolding Couplers” GB 15831.
(8) The acceptance of scaffolding couplers shall comply with the following provisions:
a) Couplers for new scaffolding shall have a production license, a test report from a legally authorized testing unit, and a product quality certificate;
b) Couplers for old scaffolding shall be inspected for quality before use. Couplers with cracks or deformation are strictly prohibited from use, and bolts with stripped threads must be replaced.
c) Couplers for both new and old scaffolding shall be rust-proofed;
d) Couplers used in the support structure shall not be damaged when the bolt tightening torque reaches 65 N·m.
(9) Welding electrodes used for connections shall comply with the provisions of the current national standards “Carbon Steel Welding Electrodes” GB/T 5117 or “Low Alloy Steel Welding Electrodes” GB/T 5118.
(10) Ordinary bolts used for connections shall comply with the current national standards “Hex Head Bolts, Grade C” GB/T 5780 and “Hex Head Bolts” GB/T 5782.
(11) The manufacturing quality of combined steel formwork and accessories shall comply with the provisions of the current national standard “Technical Specification for Combined Steel Formwork” GB 50214.
3. Re-inspection of Scaffolding
The following indicators shall be re-inspected for steel pipe scaffolding couplers: mechanical properties of coupler material, appearance, weight, torque test, mechanical properties of right-angle couplers, mechanical properties of swivel couplers, and tensile properties of butt couplers. Specifically, the testing is based on GB15831-2023:
a) Right-angle coupler testing: anti-slip performance, anti-destruction performance, torsional stiffness performance
b) Swivel coupler: anti-slip performance, anti-destruction performance
c) Butt coupler: tensile performance
d) Base: compressive performance
Steel pipe: Testing is based on GB/T 3091-2015 “Welded Steel Pipes for Low-Pressure Fluid Transportation” mechanical properties (yield strength, tensile strength, elongation after fracture), and the bending test
Post time: Jan-15-2026