Normally, a load is lifted rather than raised with hydraulic jacks. Hydraulic lifting is only used when lifting with conventional lifting equipment is not possible. In practice, only a small percentage of vertical load movements are carried out using hydraulics—and for good reason. Hydraulic lifting is generally slower, more complex, and involves greater risks.
Safety Starts with Stability
When lifting a load with hydraulic equipment, the stability of the hydraulic cylinders is critical.
If the supporting surface is soft or uneven, the cylinders may not stand perfectly vertical. As a result, the heavy load can become unstable or tilt, increasing the risk of the load slipping or falling from the cylinders—with potentially serious consequences.
Even when the ground is firm and level, a load can still become unstable. For example, if one side of the load is heavier than the other, the hydraulic cylinders supporting the lighter side will extend more quickly. Hydraulic oil naturally flows along the path of least resistance.
The solution is to adjust the oil flow so that the cylinders lifting the heavier side receive more hydraulic pressure. By balancing the oil flow between all cylinders, the load can be raised evenly.
Stability Is Difficult to Monitor
When raising a load with hydraulic cylinders, it can be difficult to see whether all cylinders are extending at the same rate.
With conventional lifting equipment, an unbalanced load is usually easier to recognise and correct. During hydraulic lifting, differences in cylinder movement are often less obvious, making continuous monitoring essential.
Safety Around Hydraulic Hoses
The safety risks are not limited to the hydraulic cylinders themselves.
A damaged hydraulic hose—or one that is not rated for the required operating pressure—can fail suddenly. If this happens, hydraulic oil can be released at pressures of up to 720 bar.
A high-pressure hydraulic oil jet can penetrate up to 33 cm into soft tissue, such as a hand or leg. These injuries are extremely serious because the human body cannot break down hydraulic oil, and immediate medical treatment is essential.
For this reason, hydraulic hoses should always be inspected regularly for signs of wear, damage, or deterioration.
Annual Inspection and Proof Load Testing
Hydraulic lifting equipment—including the pump, hoses, and hydraulic cylinders—must undergo annual inspection and proof load testing.
These inspections should be carried out by a certified organisation employing suitably trained technicians.
During the inspection, the equipment is checked for leaks, damage, and wear. During proof load testing, the equipment is tested under a prescribed proof load of 105% of its rated capacity to verify that it continues to operate safely.
Experience Is Essential
Because of the many safety considerations involved, hydraulic lifting should only be carried out by experienced personnel.
For this reason, hydraulic lifting operations are often entrusted to specialist companies with the necessary expertise and equipment.
When operators are trained to use hydraulic lifting systems themselves, they are typically trained by manufacturers such as Holmatro. During lifting operations, the operator uses a control panel to regulate the hydraulic pressure supplied to each individual cylinder, ensuring that all cylinders extend at the same rate and the load remains stable throughout the lift.
Knowledge file Safe Lifting
Use lifting equipment safely and correctly. Learn how to sling loads properly and how to inspect, examine, and certify lifting equipment to ensure safe and responsible lifting operations.
