What Is Side Pull and How to Avoid It
Cranes are designed to perform lifts within the vertical plane, with any horizontal movement carefully planned and accomplished through the use of any boom extension capabilities. A side pull is a lift that is attempted with the object not directly below the hoist cables.
Side pulling or loading is an incredibly dangerous maneuver to attempt. Doing so risks damage to the hoist, shifting the load balance within the rigging, and creates an extremely hazardous work environment for nearby personnel. The most common injuries on job sites, according to OSHA, include:
- Falling or tripping
- Being struck by an object
- Caught in-between
Attempting a side pull increases the risk of all of these injuries.
Effect of a Side Pull on the Crane
When an object is lifted from an area off center from the boom or manually pulled off center by workers to reach a different position, a number of effects are placed on the crane.
- Having the lifted weight out of plumb with the crane shifts the center of balance significantly, which will increase the risk of the crane itself destabilizing and tipping over.
- Pulling from the side induces more stress on the wire rope itself. This causes the rope to dig into the hoist and trolley components, causing damage. And in the worst-case scenario, the rope itself could snap or sheer from the additional pressure. Even a slight angle can quickly add thousands of pounds of force.
- A side pull will always naturally form or want to create a pendulum action, with the load swinging from the fixed point. This swinging is widely dangerous to everything around and can be unpredictable.
Side pulling is never a good option. It introduces unnecessary risk for personnel injury and structural damage, as well as crane and rigging damage.
Prevention and Alternates to Performing a Side Pull
The most significant and first step to preventing a side pull is operator training. They should understand what a side-pull is, why it is so dangerous to perform, and the steps they need to take to ensure a vertical lift every time. Trust your operator if they voice concerns about a planned lift.
The second part of prevention comes from having a solid site plan, hazard assessment, and lift plans in place before the crane is ever on site. Mobile cranes you may be able to maneuver into a new position with some level of ease, but larger, more permanent crane installations are less adaptable. Either way, be prepared that you may need to readjust crane placement to lift around changing obstacles throughout a project.
Depending on your work site, one alternative may be the use of a portable gantry crane. These cranes allow objects up to 10,000 lb (depending on the model and need) to be lifted, turned, and moved in any direction so long as there is flat, stable ground for the crane to move along. They maintain a plump relationship between the object and hoist throughout any lateral arc.
Safety Devices for a Side Pull
As dangerous as side pulls can be, there are sometimes when there is no way around performing one to complete a job. If such action is authorized, a load moment indicator (LMI) should be installed on the crane.
This device will alert the crane operator if load conditions begin to exceed the capabilities of the equipment being used. They measure the load weight and multiply it by a measured radius of the side pull.
LMIs have the capability to take into account not only the angle of the side pull but also incorporate movements made by the crane. When these movements get close to the maximum safe allowance, they warn the crane operator, and in some installations, they can immediately halt the crane to prevent the threshold from being passed.
Comprehensive, Safe Crane Rental
No matter the job, using the right tool makes all the difference. Make sure you select a crane that fits your job site requirements for the safest and most effortless experience.
Serving the Carolinas for over 40 years, Parker’s Crane Service can help you get equipped with the right crane for the job. With a fleet of well-maintained hydraulic truck cranes, we offer not only the best equipment but can help with site installation, maintenance, and operation as well. Our crew is OSHA and MSHA compliant to ensure your site and crew safety.
We pride ourselves on safety and our Zero Accident Philosophy and conduct many detailed safety measures when performing a job to ensure that no project carries unnecessary risk. We perform the following for every single job we take:
- Pre-lift Job Assessments
- Daily Risk Assessments
- On-site Hazard Analysis
- Routine Management Audits