External support legs, also known as landing gear, are crucial components for trailers, especially semi - trailers. As a supplier of external support legs, I've seen firsthand how these devices work and their importance in the transportation industry. In this blog, I'll break down how external support legs operate and why they matter.
The Basics of External Support Legs
External support legs are typically attached to the front end of a semi - trailer. Their main job is to support the trailer when it's detached from the tractor unit. When a trailer is unhitched, it needs a stable base to rest on, and that's where the support legs come in. They prevent the trailer from tipping over or sagging, which could cause damage to the trailer and its contents.
How They're Built
Most external support legs are made of high - strength steel to withstand the weight of the trailer. They usually consist of two main parts: the inner leg and the outer leg. The inner leg slides inside the outer leg, allowing for adjustable height. There's also a gearbox or a hydraulic system that controls the extension and retraction of the legs.
Manual vs. Hydraulic Systems
Manual External Support Legs
Manual support legs are the more traditional type. They're operated by a hand - crank mechanism. When you turn the crank, a gear system inside the leg causes the inner leg to move up or down. It's a simple and reliable method, but it can be time - consuming and physically demanding, especially when dealing with heavy trailers. For smaller trailers or in situations where power isn't readily available, manual legs are a great option.
Hydraulic External Support Legs
Hydraulic support legs, on the other hand, use a hydraulic system to extend and retract. A hydraulic pump, usually powered by the trailer's electrical system or a separate power unit, forces hydraulic fluid into cylinders within the legs. This pressure causes the inner legs to move. Hydraulic legs are much faster and easier to operate than manual ones. You can adjust the height of the legs with just the push of a button. They're ideal for larger trailers or when you need to make quick adjustments.
The Operation Process
Extending the Legs
When you're about to unhitch the trailer, the first step is to extend the support legs. If it's a manual leg, you'll start turning the hand - crank clockwise. As you turn, you'll feel the leg start to lower. Keep turning until the leg makes firm contact with the ground. You should turn a few extra times to ensure the leg is fully extended and stable.
For hydraulic legs, you'll activate the hydraulic pump. The pump will start pushing fluid into the cylinders, and the legs will begin to lower. You can monitor the process through a control panel. Once the legs touch the ground, you can adjust the height to make sure the trailer is level.
Retracting the Legs
When it's time to hitch the trailer back to the tractor, you need to retract the support legs. For manual legs, you'll turn the hand - crank counter - clockwise. As you do, the inner leg will start to rise back into the outer leg. Keep turning until the leg is fully retracted.
With hydraulic legs, you'll reverse the flow of the hydraulic fluid. This will cause the cylinders to retract the inner legs. Again, you can control this process from the control panel.
Why External Support Legs Are Important
External support legs play a vital role in the safety and functionality of trailers. They provide a stable base for the trailer when it's not attached to the tractor. This prevents the trailer from tipping over, which could lead to serious accidents and damage to the cargo. They also make it easier to load and unload the trailer. When the trailer is level and stable, it's much safer for workers to move goods in and out.
Complementary Trailer Accessories
As a supplier of external support legs, I also offer other trailer accessories that work in tandem with these legs. For example, the Semi Trailer 90 Prefabricated Kingpin is an essential part for connecting the trailer to the tractor. It ensures a secure and stable connection, which is crucial when the trailer is in motion.
The Single Point Suspension helps to improve the ride quality of the trailer. It absorbs shocks and vibrations, reducing wear and tear on the trailer and its contents. This is especially important when transporting fragile or sensitive goods.
Another important accessory is the Air Brake Tanks. They store compressed air, which is used to operate the trailer's braking system. A well - functioning braking system is essential for the safety of the trailer and everyone on the road.
Conclusion
External support legs are an integral part of any trailer. Whether you're using a manual or hydraulic system, these legs provide the stability and support needed when the trailer is unhitched. As a supplier, I understand the importance of high - quality external support legs and complementary accessories. If you're in the market for external support legs or any of the related trailer accessories, I'd love to have a chat with you. We can discuss your specific needs and find the best solutions for your trailers. Don't hesitate to reach out to start a procurement discussion.
References
- "Trailer Handbook" - A comprehensive guide on trailer components and operation.
- Industry research papers on trailer safety and equipment functionality.
