Different arrangements carry forces differently

A beam suspended from an upper connection and a spreader supported by inclined upper slings do not behave in the same structural way. Compression is a principal force in a spreader. The actual arrangement must match its design and instructions.

Within the range of Slings and lifting accessories, these devices can control inward pull, maintain separation or accommodate asymmetric loads. Moving a connection or using a different hole changes the configuration and requires confirmation that the arrangement is permitted.

Information needed for selection

The load’s weight, centre of gravity and lifting point characteristics must be known. Beam self-weight, lower accessories and crane capacity also matter. Everything suspended from the crane uses part of the available capacity.

Headroom can constrain the solution. Allowance is needed for the hook, connections, slings, beam and load, as well as nearby obstructions. A beam may approach an overhead crane’s structure before the hook reaches its upper travel limit, so the hook limit alone is not sufficient clearance information.

Load distribution and stability

Several attachment points do not guarantee equal forces at every point. The centre of gravity, stiffness of the workpiece and arrangement geometry determine distribution. An apparently symmetrical layout can conceal unequal loading, particularly when the load itself is not symmetrical.

Replacing long slings with a beam can also change stability. Where lifting points sit below the centre of gravity, a competent assessment is particularly important to establish whether the load may tilt or rotate. An improvised trial cannot replace that assessment.

Identification and inspection

Identification, capacities and permitted configurations must be legible and consistent with the documentation. Checks address distortion, corrosion, local damage, welded details and connections, including moving components on adjustable beams.

Damage or inconsistent documentation requires the device to be set aside for competent assessment. Repairs, welding or alterations can change its strength and conditions of use. Storage and handling should prevent impacts and deterioration that could compromise the next lift. These principles do not provide a method for designing a lifting beam.