A basic lifting beam design plays a big role in major hoisting purposes. Few of the erectors and riggers involve a big part of lifting beams in general lifting operations. Technically discussing, a lifting beam design uses two places of arrangement with the object which is to be lifted that avoids over stressing in case a single attachment is used. Here, a straight pull is used instead of an oblique pull, when chokers are used.
It is also necessary to reduce unwanted erection stresses in some instances. Like for say, the oblique pull might create excessive compression in the top chord in case chord is unbraced laterally.
A little adjustment in the structure of a basic lifting beam can help in alleviation where optimum choker locations can reduce the stress while working for the erection phase.
Different Elements Used in a Lifting Beam Design
The commonly used elements associated with lifting beams are-
- Shackles are used for connecting the lines with a lifting beam design and come in different variations and capacities to meet the desired needs.
- The multiple loads used with the beams represent the average industry loads that are for comparison purposes only.
- Chokers are used to be wrapped around the object that is to be lifted. They are fastened to the lifting beam underside by using shackles.
- Slings are used for suspension of lifting beams from the main hook.
- Hooks are less popular to be attached to a lifting beam because the hole needed in a lug plate must be large enough along with a great edge distance on the lifting lug to accommodate hook profile.
- Hooks with the safety latches are used to prevent the lines or shackles from escaping the hook throat.
- Varied properties of a shackle to keep a close eye on are- load capacity, pin diameter, shackle length, diameter flange and jaws width.
While working with an optimum lifting beam design, it is important to carry a desired lifting beam capacity. It can be established by maintaining the governing geometry of a device which is maximum length and spacing of the bottom and top lugs.
Any beam limitation should also be taken into account, such as considering the line angle of the lifting beam design or using constant section beam.
In a Nutshell
There are several factors that must be monitored while looking for the static weight of the objects which is to be lifted. Here, cases might occur when an additional safety factor is added to the static load to get the safest results.
This blog has been penned down by author who is a trained engineer and blogger at Bishop Lifting Services. His writing skills are meant to demonstrate the exclusive features of diverse lifting beam designs.