First, the requirements for erecting ground-supported scaffolding:
a) The scaffolding erection height should generally not exceed 20m.
b) The overall structure of the scaffolding should extend 300mm beyond both ends of the working surface in both directions, and 300mm beyond the working surface in both directions in both directions.
c) If the scaffolding exceeds three layers, it should be fixed to the ship’s structure with bracing. The longitudinal distance between each bracing should not exceed three layers (i.e., no more than 6m); the lateral distance should also not exceed 6m, and there should be at least two bracings. (See the diagram on the right.)
d) Bracing welding requirements: Bracing is required to fix the scaffolding to the ship’s structure. The bracing plates should be made of 10mm steel. The weld at the connection with the ship’s structure should be a double-sided continuous weld with corner wrapping, and the weld leg should be no less than 6mm. Strictly control the welding quality to prevent porosity, slag inclusions, weld beads, etc.
e) The distance between the scaffolding and the ship or other objects should generally not exceed 100mm, and in special circumstances, not exceed 300mm. If the ship’s shape changes and this requirement cannot be met, effective auxiliary measures, such as adding railings or safety nets, should be taken to prevent falls. The first safety railing should be approximately 500mm high, and the second approximately 1200mm high, and both should be sturdy and reliable.
f) For some special painting operations, protective padding should be added to areas where displacement and friction are likely to occur between scaffolding components. No part of the scaffolding should touch the working structure, and a distance of 150mm to 300mm should be maintained.
g) Emergency passages and work walkways on and off the scaffolding should be kept clear and not obstructed.
Second, Requirements for the Setting Parameters of Components for Ground-Based Scaffolding
1) Uprights
a) The vertical deviation of the entire scaffolding uprights should not exceed L/1000 mm.
b) Except for the top step of the top floor, all other joints on each floor and step of the uprights should be connected using butt-joint couplers.
2) Horizontal Bars
a) A small horizontal bar should be installed at each main node and fixed to the main horizontal bar.
b) The main and small horizontal bars should be kept horizontal; the horizontal deviation should not exceed 5mm/m.
3) Scaffold Boards
a) The height of the scaffold board from the working surface should not be less than 300mm.
b) The working surface width of the scaffold board should generally not be less than 600mm, and should not be less than 300mm in special circumstances.
c) The maximum gap between two parallel scaffold boards should not exceed 20mm.
d) The scaffold boards must be laid neatly and tightly, and no gaps are allowed.
e) After laying, the scaffold boards must be bound and fixed with multiple strands of wire, with the wire folded towards the inside of the scaffold board.
f) For structures with large linear curvature, the scaffolding should be appropriately widened as needed to ensure safe operation.
4) Ladders and Safety Nets
a) Ladders must be erected between each floor and each side of scaffolding, and the ladders must be securely fastened.
b) When using inclined ladders, handrails should be installed on both sides of the ladder, and the ladder should be reliably fixed to the crossbars. The incline should generally not exceed 45°.
c) Where there is no working platform on the outside of the inclined ladder, two guardrails should be installed along the direction of the ladder, with heights of approximately 500mm and 1200mm, respectively.
d) Safety nets should be installed horizontally on all scaffolding starting from the second floor. The safety net ropes must be securely tied, and an additional net should be added every 5 floors. The installation of safety nets must be done simultaneously with the erection and dismantling process, ensuring that all installed safety nets are in good condition and that there are no other auxiliary steel pipes or other obstacles within the distance between the horizontally installed nets and the upper uprights, ensuring that workers are protected from other injuries and do not fall directly to the bottom of the scaffolding.
e) When horizontally installing safety nets, the netting radius should generally not be less than the fall radius of the working position, and the deflection of the safety net should be within 1/4 of the support spacing.
Post time: Dec-30-2025