The steering wheel of the truck-mounted crane is typically connected to the steering shaft via splines. Its primary function is to convert the force exerted by the driver on the rim of the steering wheel into torque and subsequently transmit it to the steering shaft. When a larger-diameter steering wheel is employed for steering, the manual force exerted by the driver on the steering wheel can be reduced. The steering transmission shaft serves as a connecting element between the steering gear and the steering shaft, facilitating the generalization of the steering gear, compensating for manufacturing and installation errors, and enabling a more rational installation of the steering gear and the steering wheel on the entire vehicle. Today, let’s delve into the issues that are prone to occur with the steering wheel of the crane.
Problem 1: Poor steering wheel return performance
Failure description:
After the vehicle makes a turn, the steering wheel is capable of returning either without the application of force or with a minimal force applied to it. However, the steering wheel fails to actually return to its original position.
Failure analysis:
Insufficient tire inflation.
Inadequate lubrication of the rod system ball joint.
Incorrect alignment of the front wheels.
Lack of oil and seizure in the steering vertical arm bearing.
The ball joint pin of the steering linkage is seized.
Improper adjustment of the steering wheel, resulting in friction with the outer cover.
The steering column bearing is overly tight or seized.
The distribution valve is stuck or clogged.
The return hose is twisted and blocked.
The mating surface of the relative movement of the steering shaft is overly tight.
Improper adjustment of the tie rod, as depicted in the illustration, where the toe-in is excessive, or conversely, it is insufficient.
Trouble shooting methods:
Inflate the tires in accordance with the specified air pressure.
Lubricate or replace the rod system ball joint.
Inspect and adjust the parameters of the front wheel alignment.
Examine the working condition of the vertical arm bearing, add oil, and adjust it to the stipulated requirements.
Repair or replace the ball joint pin of the steering linkage.
Re-adjust the steering wheel and (or the outer cover) to eliminate any interference.
Adjust or replace the bearing.
Remove the distribution valve for cleaning or replacement.
Adjust the twisted hose. If it cannot be repaired, it should be replaced.
Jack up the vehicle, remove the longitudinal tie rod that governs the steering shaft, and manually rotate the wheel. If it feels heavy, it is necessary to inspect whether the mating surfaces of the kingpin, the trapezoidal tie rod, etc. are seized and whether there is a deficiency of lubricating oil at the kingpin and thrust bearing, and address the issue specifically.
Problem 2: Heavy steering on one side
Failure description:
During driving, when the steering wheel is turned from the neutral position to one side, the steering becomes heavy.
Failure analysis:
Insufficient tire pressure on one side of the wheel.
The steering gear experiences leakage exclusively in one direction.
When driving in a straight line, the distribution valve fails to return to the neutral position or there is a seizure phenomenon.
Trouble shooting methods:
Inflate the tire in accordance with the specified air pressure.
Identify the location of the leakage, repair or replace the worn components.
When the steering gear is in the neutral position, check the pressure at the A and B power oil ports to determine if the distribution valve reverts to the neutral position. If there is pressure at one of the ports, it is necessary to repair and replace the relevant components. If it is seized, it is essential to clean the distribution valve to resolve the issue.
Problem 3: Heavy steering when quickly turning the steering wheel
Failure description:
When the vehicle is in motion and the steering wheel is rapidly turned, a significant increase in steering force is felt.
Failure analysis:
The oil inlet pipeline is obstructed and the pump is unable to suck in oil.
Excessive internal leakage within the oil pump.
Trouble shooting methods:
Add oil as necessary.
Utilize a pressure gauge to check the pressure of the oil pump. If it fails to meet the requirements, it should be repaired or a new pump should be substituted.
Problem 4: Excessive free play of the steering wheel
Failure description:
During driving, the vehicle is unable to maintain a straight trajectory. When observing the vehicle’s straight-line driving from the rear, it moves in an S-shaped pattern.
Failure analysis:
The meshing clearance between the rack and the gear sector of the steering gear is overly large, resulting in excessive steering free play.
The bearing of the steering gear is worn, contributing to excessive steering free play.
The fastening bolts of the steering gear are loose, causing the steering gear to displace and leading to excessive steering free play.
The ball joint pin of the steering tie rod is worn, resulting in excessive steering free play of the steering gear.
The wear of the steering universal joint causes excessive steering free play.
The connecting bolts (nuts) between the steering column, the transmission shaft, and the steering gear are loose, resulting in excessive free play.
The connection between the steering wheel and the steering column is loose. On one hand, the key may be loose. On the other hand, the fastening nut is loose, causing excessive steering free play.
Trouble shooting methods:
Adjust the relative position of the rack and the gear sector of the steering gear to reduce the meshing clearance.
Replace the supporting bearing of the steering gear.
Tighten the bolts of the steering gear to eliminate the relative displacement.
Tighten or replace the ball joint pin of the steering tie rod.
Replace the universal joint of the transmission shaft or the bearing of the universal joint.
Tighten the connecting bolts between the steering column, the transmission shaft, and the steering gear.
Replace the steering wheel or the steering column and tighten the nut.
In conclusion, addressing issues with the steering wheel of a truck-mounted crane requires a detailed understanding of the possible causes and the corresponding troubleshooting methods. Regular inspections and maintenance can help identify and rectify these problems promptly, ensuring the safe and efficient operation of the vehicle. By being vigilant and proactive in dealing with steering wheel problems, operators can minimize the risk of accidents and ensure the smooth performance of the truck-mounted crane on the road.
