Side overturning is the most dangerous accident for truck mounted crane operators. Unlike fixed tower cranes, a truck mounted crane relies on the chassis and outriggers to keep balance. Overloading, improper outrigger setup, uneven ground and wrong lifting radius are the top causes of side overturning. Below are practical safety rules to reduce overturning risks for your truck crane.https://www.hjtrailer.com/construction-machinery/truck-mounted-crane/dual-purpose-straight-arm-truck-mounted-crane.html
First, check the ground condition before lifting. Never set outriggers on soft soil, backfilled mud, sloped ground or hollow areas. Soft ground will let outriggers sink gradually under load. Place thick steel plates or hardwood pads under each outrigger base to spread pressure and avoid sinking. The whole truck chassis must be kept as horizontal as possible.
Fully extend and lock all outriggers. Many operators skip full extension to save time. Partially extended outriggers greatly shrink the stable supporting area. For straight boom crane and knuckle boom crane, all four outriggers must be deployed and locked. Adjust each outrigger individually until the chassis does not rock. Do not use tires to share lifting load; tires are not designed for supporting crane lifting force.
Strictly follow the lifting capacity chart. The rated lifting weight of the truck mounted crane changes with lifting radius and boom angle. Many buyers misunderstand the maximum marked tonnage as the load available at any position. When the boom extends farther and the radius increases, the safe lifting capacity drops sharply. A load moment indicator (LMI) can give an alarm before the dangerous limit is reached; do not disable this safety alarm.
Avoid side lifting and diagonal pulling. The truck crane is designed for vertical lifting. Side pulling or dragging goods sideways creates huge lateral force, which easily causes side overturning. If the cargo is stuck on the ground, do not lift hard with the crane. Free the obstacle first before hoisting.
Control the lifting speed smoothly. Rapid lifting, sudden stop, fast slewing and sharp swing of heavy loads generate extra dynamic inertia. This lateral shock will break the balance instantly. Swing heavy objects slowly and steadily, especially when the boom is long and the radius is large.
Do not modify the crane or remove safety devices privately. Cutting the subframe, changing outrigger length or removing the LMI alarm will invalidate the safety margin. The reinforced subframe for crane is a key structure connecting the crane and truck chassis; any unauthorized modification will weaken stability.
Pay attention to weather conditions. Strong wind is a hidden danger for truck mounted cranes. Wind pushes the suspended load and creates side force. Stop lifting work when wind speed exceeds the limit stated by the crane manufacturer.
Regular inspection of core safety parts matters. Check outrigger cylinders, hydraulic seals, pins, connecting hinges and anti-explosion valves frequently. Leaking hydraulic cylinders or stuck outriggers may cause sudden collapse during lifting.
For overseas customers who buy HOWO or RHD truck mounted crane, our factory equips standard load moment protection and anti-explosion valves. We also provide operation manuals and safety training guidance.
If you need a stable truck mounted crane with reliable anti-overturn protection for construction and loading jobs, welcome to send us your working conditions for matching advice.
