Choosing the correct lifting equipment is essential. It greatly affects on-site productivity, safety, and efficiency. As an example, chain hoists, cranes, and slings can all be misused if not properly rated, sized, or placed. Chain hoists have weight ratings, slings have angle allowances, and cranes have lifting reach requirements. Choosing the wrong equipment can result in accidents and injuries.
When determining what lifting equipment to use, the load should be the first consideration. Ask yourself the following. How much does the load weigh? What is the shape of the load? Where is the load going? Lastly, how often will this be done? Answering the above questions greatly helps in narrowing down the list of potential lifting solutions.
Overhead Cranes
Overhead bridge cranes are the best lifting solution for a manufacturing bay that deals with heavy loads consistently. Once the tracks are installed, bridge cranes are designed to handle a lot of lifting with little to no ground space to spare. With bridge cranes, the cost of the equipment itself is a large trade off since you are committing to a long term installation. If there is uncertainty of how an area will be used in the next few years, consider other lifting equipment that has less of a commitment.
Gantry Cranes
The portable option of a gantry crane allows for similar functionality but with more flexibility. You can easily relocate a portable gantry crane to different sites, change the height of the beam, and bring the crane to the site to lift the load. A portable gantry system is advantageous for workshops that require infrequent large load movement, but a fixed system would be overkill, and for fabrication workshops that have movement of work throughout the site. A portable system does have limitations compared with a fixed overhead system, such as a limited lifting capacity and a requirement for level, solid ground to safely operate.
Jib Cranes
When the majority of lifting work is performed near a single location, such as feeding a machine or moving components that are within a workstation, the most economical lifting solution is most often a jib crane. A gantry crane would take up a significant amount of floor space, but a wall-mounted or floor-mounted jib crane with a 180- or 360-degree rotation does not. Jib cranes are widely used in engineering workshops, production assembly lines, and loading bays, when lifting operations are within the lift radius, and loads remain within the capacity of the jib crane arm.
Chain hoists and electric hoists
When the supporting structure is already built, and you need a mechanism to provide lifting, a hoist (usually mounted to a beam or a trolley) is the answer. Manual chain hoists are simple and reliable, and they do not need a power supply. This makes them useful in situations where electricity is not available or where there is not enough demand to justify an electric unit. Electric hoists are needed to perform lifting operations more efficiently, and they help minimize fatigue during the performance of repetitive tasks. Hoists, whether manual or electric, come in a wide range of capacities, and need to be matched to the task with due consideration. Otherwise, a hoist with insufficient capacity will, in addition to very quickly deteriorating, become a safety concern.
Lifting slings and accessories
Lifting operations are not complete without accessories, and they are by far the most error-prone. Chain slings are best used with heavy, rough, and hot loads, and they have a long useful life with the right maintenance. Webbing slings are lighter and do not damage surfaces of loads that are delicate or have a finishing, but they are more vulnerable to damage from cuts, abrasions, and UV, and therefore deserve a more thorough inspection prior to each use. The rated capacity of a sling is also highly dependent on the lifting angle, as a slingset at a 60-degree angle from vertical will have a significantly reduced capacity compared to the same slingset assembled in vertical configuration. This is the most common cause of error.
Shackles, eyebolts, and other hardware all have their own SWL ratings and all need to be within their LOLER examinations. No matter how appealing a piece of accessories is, if their certificate is out-of-date, they are illegal to use.
The one rule that covers all of it
Equipment on site should be appropriate to the lift. If the equipment on site does not suit the lift, the lift should not be adapted to the equipment available. Getting the right equipment should be the answer. This is where improvised rigging arrangements start, and adapted arrangements are where most incidents commence.
