| 1 | Match the frame to the cylinders | Check cylinder diameter, height, valve position, quantity, and filled weight against the frame’s internal dimensions and rated capacity. | Confirm that cylinders sit upright without forcing them into place. Allow clearance for valve protection and ensure the maximum gross load is not exceeded. | A correct fit reduces movement, impact, and instability during lifting or road transport. | Critical |
| 2 | Evaluate the frame material | Review the structural steel grade, tube or angle thickness, corrosion protection, and material traceability. | Ask for material certificates where required. Inspect for uniform sections, adequate wall thickness, smooth edges, and a coating suitable for the operating environment. | Appropriate material strength and corrosion resistance help preserve load capacity and service life. | Critical |
| 3 | Inspect welding quality | Examine weld continuity, joint design, penetration, surface finish, and the fabricator’s welding inspection records. | Look for cracks, undercut, overlap, excessive spatter, visible pores, incomplete fusion, and sharp weld projections. Request visual inspection records and, for critical joints, suitable non-destructive testing. | Defective welds can reduce structural strength and may fail under vibration, impact, or repeated lifting. | Critical |
| 4 | Check cylinder-retention systems | Assess chains, straps, clamps, support bars, locking pins, and the number of restraint points provided for each cylinder. | Restraints should be adjustable, secure, easy to inspect, and capable of preventing both vertical and lateral movement. Contact surfaces should not damage cylinder walls. | Reliable restraints reduce the risk of cylinders falling, rolling, or striking one another. | Critical |
| 5 | Verify protective features | Review valve guards, top and bottom rails, impact protection, anti-slip supports, and measures that prevent cylinder-to-cylinder contact. | Confirm that valves remain protected during handling and that the frame has no exposed sharp corners or protrusions likely to damage cylinders, lifting equipment, or workers. | Protective components help prevent valve damage, impact injuries, and accidental gas release. | Critical |
| 6 | Assess lifting and transport safety | Check lifting lugs, forklift pockets, base stability, center-of-gravity information, tie-down points, and compatibility with the intended vehicle or handling equipment. | Lifting points should be clearly marked and free from deformation. Forklift pockets should provide adequate clearance, and the loaded frame should remain stable when moved. | Proper handling features reduce dropped-load risks and help prevent tipping during loading, unloading, and transport. | High |
| 7 | Confirm compliance and maintainability | Review applicable transport, lifting, pressure-gas, workplace-safety, and local regulatory requirements before purchase. | Obtain drawings, rated-load information, inspection instructions, coating details, replacement-part availability, and a documented inspection schedule. | Compliance documentation and maintainability support safe use, periodic inspection, and long-term operating cost control. | High |