Telescopic Cylinders

Telescopic Cylinders

Instead of a singular hydraulic piston, telescopic cylinders have multiple piston rods which extend out from the cylinder. The multiple rods allow for greater extension from the cylinder and are able to achieve longer strokes without requiring more original area. The stroke of a hydraulic cylinder is the length to which the pistons extend at their fullest. This information is often used to classify a cylinder and its potential output in terms of power. As telescopic cylinders extend far beyond the limits of standard hydraulic cylinders without requiring a greater area, they are often used in jobs where severe space limitations exist, or where long distances are needed to be covered. For example, telescopic cylinders are used for a lifting machine necessary for the construction of high rise buildings, or the dump extension of a garbage truck. Agriculture, construction and manufacturing industries all use various sizes of telescopic cylinder to achieve certain tasks.

As with hydraulic cylinders, telescopic cylinders can be single acting, or double acting. Single acting telescopic cylinders use external forces such as gravity and machine weight to retract after extending. As the hydraulic motion works in one direction, there must be enough force to reverse the process in order to bring the pistons back to the barrel. In a double acting telescopic cylinder, the hydraulic pressure created is used to move the pistons in both directions, resulting in a greater speed of operation as there is no need to rely on gravity or weight for the retraction process. It also allows for both directions of the operation to be used to both push and pull. The mechanism is more complicated in design and more expensive to manufacture, but is widely used especially in construction machines. Custom designs of telescopic cylinders are available for manufacture, especially for specialized purposes. The factors to be considered are the same as with other cylinders - the materials used for construction, the desired stroke length and output and the mounting or setup of the cylinder itself. Replacement cylinders, seals and components are available ensuring the long lifespan of the machine as long as it is carefully maintained. Hydraulic fluids of either oil or water will have to be replaced or refilled from time to time as well.