Tie Rod Hydraulic Cylinders
Industrial manufacturing, automotive, construction, aerospace, military, oil and gas industries commonly utilize the strength, durability and productivity of tie rod hydraulic cylinders. In addition to maintaining much of work load, the rods serve as stabilizers. The tremendous force generated by hydraulic motors and pumps often creates unintentional oscillations of the cylinder, which are diminished by tie rod support. That same force is also problematic for loose end caps. Tie rods resolve this problem by holding them firmly in place. Spacecraft, ships, cranes, wind turbines, braking mechanisms, lifts, oil rigs, bridges, towers and other structural and industrial equipment use tie rod cylinders to produce very high force with a relatively small motor and supply of pressurized fluid. As the additional rods and mounting can significantly add to the overall dimensions of the hydraulic cylinder, this particular type of device is found more often in immobile equipment while welded hydraulic cylinders are utilized in applications that necessitate portability.
The general design and function of tie rod hydraulic cylinders is quite simple. The main body of the cylinder is a tube like barrel that houses and connects all of the required components. Both ends of the cylinder are closed off by a cap. One cap, or both in the case of double acting hydraulic cylinders, has a round seal through which the piston rod may move in and out. The external portion of this rod is attached to the equipment or load to be moved. The internal end of the rod is secured to the hydraulic piston, a disc-like part that rests in the cross-section of the barrel, dividing it into two chambers. When pressurized hydraulic fluid enters the non-rod side of the compartment, the piston is engaged and the rod extended. When fluid enters the rod side chamber, the piston moves in the opposite direction and the rod is retracted. In tie rod cylinders, cold-rolled high strength tempered steel rods are attached through various methods to both end caps. Most commonly rods are threaded and screwed into drilled holes or shackles. Small cylinders usually have 4 rods, while as many as 20 tie rods are needed for larger industrial models. The working strength of each rod is calculated based on the allowable working stress and the minimum cross-sectional area. It is integral to productivity and safety that the dimensions and tensile strength of tie rod hydraulic cylinders be calibrated to match the specific application for which they are used.
