The trailer support arm is a core device that ensures stability during trailer operations. It is primarily used to support the vehicle body during parking, loading and unloading goods, or maintenance, preventing tilting, sinking, or accidental movement. Proper use of the support arm not only protects the trailer structure but also avoids personal injury and cargo damage. The following provides a detailed explanation of its usage specifications from four aspects: preliminary preparation, operational steps, precautions, and storage and maintenance.
I. Preliminary preparation: Before using the support arm, ensure safety by completing three key inspections to eliminate potential risks: 1. Support arm self-inspection: Check the support arm for any damage such as deformation, cracks, or loose bolts; for hydraulic support arms, check for oil pipe leaks and ensure the oil level is normal; for mechanical support arms, confirm the flexibility of the handle and lock latch. 2. Trailer status confirmation: Park the trailer on a solid and flat surface (avoid soft soil or slopes), apply the handbrake, and engage neutral gear (P gear for automatic vehicles). If there is a towing vehicle, disconnect it. 3. Ground treatment: If the ground is soft (such as grass or sand), place a wooden board (thickness ≥5cm, area ≥2 times the size of the support leg) under the support leg to prevent it from sinking; in icy and snowy weather, place anti-slip pads to avoid slipping.
II. Operational Steps: Standardize Procedures to Ensure Stability. Taking the commonly seen manually folding support arm as an example, the operational steps are as follows:
1. Position the support arms: Locate the support arm mounting points on both sides of the trailer chassis (usually located under the frame, near the wheels), and confirm that the connection between the support arm and the mounting point is secure. Some trailer support arms can be adjusted laterally, and they need to be moved to an area where the body weight is evenly distributed (avoiding areas near the cantilever end).
2. Unfolding and Adjusting Length - Unlocking the Folding Mechanism: Pull the lock catch on the support arm to unfold the folded support arm downwards until it is vertical; - Adjusting the Height of Support Legs: Rotate the handle (or hydraulic switch) to slowly lower the support legs until they touch the ground (or skid). At this point, the support arm should be perpendicular to the ground. If the ground is slanted, the angle of the support legs needs to be slightly adjusted (some support legs can rotate 360°).
3. Force Balance Adjustment - Synchronized Adjustment: The support arms on both the left and right sides need to be adjusted alternately. Each rotation of the handle should not exceed 3 turns to ensure that the heights on both sides are consistent (a level gauge can be used to measure the side of the vehicle body). - Load Bearing Control: The support arms need to bear part of the weight of the vehicle body, but they should not completely lift the trailer off the ground (the tires still need to contact the ground for more than 1/3 of their area) to avoid overload of the support arms. If the vehicle body needs to be kept level when loading or unloading goods, the height of one side can be slightly adjusted according to the center of gravity of the goods.
4. Locking and Stability Check - Locking Mechanism: After adjustment, fasten the mechanical lock of the support arm (close the pressure relief valve for hydraulic type) to prevent accidental retraction of the support arm; - Stability Test: Push the side of the trailer with your hand to observe if there is any shaking; check if the support feet are slipping, and if the skids are displaced, ensuring there are no signs of loosening.
III. Precautions: Key to Avoiding Risks 1. Overloading is prohibited: The support arm has a rated load capacity (usually marked on the arm body), and it must not exceed its maximum load (for example, the rated load capacity of a 5-ton trailer support arm is about 2 tons). Otherwise, it may cause deformation or fracture of the arm body; 2. Symmetrical loading: When loading and unloading goods, the goods should be evenly distributed in the center of the trailer to avoid uneven loading on the support arm due to excessive weight on one side; 3. Keep away from dangerous areas: When the support arm is in operation, personnel are prohibited from standing under the support arm or in the direction of the tilting trailer to prevent injury from the support arm failing; 4. Dynamic monitoring: Regular checks on the condition of the support arm are required for prolonged use (such as overnight parking). If the support feet sink or the body tilts, adjustments should be made promptly; 5. Special attention for hydraulic models: Hydraulic support arms must avoid rough operation of switches to prevent oil pipe bursting; before use in winter, the hydraulic oil needs to be preheated (by idling the trailer engine for 10 minutes).
IV. Storage and Maintenance: Extending Service Life 1. Storage Steps - Unlocking the mechanism: Release the latch or open the hydraulic pressure relief valve; - Retracting the support arm: Rotate the handle in the opposite direction to make the support leg about 10cm off the ground; - Folding and securing: Fold the support arm upwards, tighten the folding latch, and ensure that the support arm is firmly attached to the chassis without any shaking.
2. Routine maintenance - Cleaning: After each use, remove the soil and gravel from the support legs and arm body to prevent rusting; - Lubrication: Apply lubricating oil (such as butter) to the folding joints and handle screws monthly to maintain flexibility; - Rust prevention: If rust appears on the support arm, sand it down with sandpaper and apply anti-rust paint; - Hydraulic system maintenance: Check the hydraulic oil level every six months and replenish with the same type of hydraulic oil; replace the seals once a year to prevent leakage.
V. Common Errors and Avoidance - Error 1: Soft ground without wooden planks → Consequence: Supporting feet sink, trailer tilts → Avoidance: Wooden planks or steel plates must be placed; - Error 2: One-sided support arm too high → Consequence: Vehicle body tilts, support arm breaks → Avoidance: Synchronously adjust the height of both sides, calibrate with a level meter; - Error 3: Forgetting to lock the mechanism → Consequence: Support arm retracts, trailer collapses → Avoidance: Repeat check the status of the lock catch after operation; - Error 4: Support arm not perpendicular to the ground → Consequence: Supporting feet slip → Avoidance: Adjust the angle of the support arm to be perpendicular.
The use of the trailer support arm may seem simple, but it actually concerns safety. Following standardized procedures and paying attention to detail inspection are crucial to maximize the effectiveness of the support arm. Remember: safety is not trivial, and every step needs to be taken carefully!
