Are you designing your own log splitter, modernizing a front loader, or perhaps building a workshop press? At the heart of each of these systems is a hydraulic cylinder. Choosing the right model is not just a matter of eyeballing the dimensions, but above all, understanding the basics of physics and flow. An underpowered component will not handle the load, while an oversized one will make the machine move frustratingly slowly. The experts at BRhydraulic explain what to pay attention to when buying a hydraulic cylinder so that your construction works flawlessly.
1. Piston diameter and powerful pressing force
When buying a hydraulic cylinder, you need to distinguish between two key diameters: the outer diameter of the shiny piston rod and the inner diameter of the cylinder (i.e., the size of the piston hidden inside). It is this second dimension that is crucial for the power of your machine.
The force generated by a hydraulic cylinder is directly determined by the oil pressure and the piston area. The relationship is simple: the thicker the piston (the larger the inner diameter of the tube), the greater the pushing force at the same pump pressure. If you are building a hard wood splitter and need a pressing force of around 15-20 tons, a small hydraulic cylinder will simply stall on a knot, causing the relief valve to open.
2. Extension speed – the "oversized" cylinder trap
It might seem that it is best to buy the largest possible hydraulic cylinder and have extra power. However, this is a mistake. A huge cylinder requires a massive amount of oil to fill its chamber. If your hydraulic pump has a low flow rate (liters per minute), and you use a powerful hydraulic cylinder (e.g. with a 140 mm piston), extending the piston rod all the way will take ages. When selecting components, you must always balance the lifting force with the machine's operating speed.
3. Stroke and retracted length
Every hydraulic cylinder has a specific retracted length (fully retracted) and a maximum extension range (stroke). Before welding mounting ears to the machine frame, make sure that:
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The cylinder fits in the designated space when retracted.
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Its full stroke allows for the full range of motion (e.g. completely closing the bucket or splitting a log all the way through).
4. Mounting – how not to destroy the equipment on the first day?
Even the most expensive and durable hydraulic cylinder will fail quickly (leaks or bent piston rod), if it is mounted rigidly and crookedly. During operation under load, every even the sturdiest steel machine frame flexes and deforms slightly.
Therefore, a professional hydraulic cylinder should be mounted on so-called spherical bearings (rod ends). They allow for minimal side tilting during operation, compensating for stresses. Rigid mounting "on a solid pin" is the easiest way to destroy the cylinder barrel and seals.
Choosing the right components is the foundation of a successful design. Regardless of whether you need a compact element for power steering assistance, or powerful equipment for construction machinery, you will find a reliable hydraulic cylinder in the offer of the BRhydraulic.eu store. Our team will help you calculate the parameters and select equipment perfectly tailored to your machine.
