Question 60

The Correct Answer is C **Explanation of Correct Option (C): It will protect the upper part of a load** A spreader bar (or lifting beam) is specifically designed to distribute the lifting force over a wider area, preventing the lifting slings from squeezing, crushing, or damaging the load. When lifting long or sensitive cargo, the slings connected to the main hook would naturally exert inward tension as they lift. The spreader bar keeps the attachment points fixed at the width of the load, ensuring the slings remain vertical or close to vertical. This configuration prevents the compressive forces that could damage the edges, walls, or structure (the upper part) of the cargo, making protection the primary purpose. **Explanation of Incorrect Options:** **A) It will increase the lifting radius:** The lifting radius is the horizontal distance from the center of rotation of the crane to the center of the hook/load. Adding a spreader bar does not change the geometry of the crane boom necessary to increase this distance. **B) It will protect the slings:** While a spreader bar keeps the slings positioned properly, its primary function is load protection. Slings are robust lifting gear; they are protected by wear pads or edge protectors, not by the introduction of the spreader bar itself. The bar's design focuses on preventing damage to the cargo. **D) It will increase the lifting capacity:** The lifting capacity is determined by the crane's rating, its configuration (radius, boom angle), and the strength of the rigging components (slings, shackles). A spreader bar adds weight (tare weight) and must be factored *against* the crane's capacity. It does not increase the maximum weight the system can safely lift.