High Pressure Hydraulic Valves And Directional Control
Directional control valves, a type of high pressure hydraulic valve, are one of the most fundamental components in the hydraulics industry. Essentially, directional control valves are designed to channel fluid along different paths from multiple sources. They are usually composed of a piston inside an electrically controlled cylinder, the movement of which either permits or restricts flow. Though technicians say ‘fluid’, in fact directional control valves may be hydraulic or pneumatic (i.e. controlled by compressed air).
Directional control valves are known as discrete valves, for the way that they shift from entirely open to fully closed, lacking the capacity to shift into intermediate positions the way proportional valves can. This results in the relatively heavy shock forces high pressure hydraulic valve systems have to deal with – fluids shift in an instant, accelerating and decelerating rapidly, a movement that often causes so-called ‘fluid hammer’, the loud noise that comes from within hydraulic machines and resembles that of a hammer striking a blacksmith’s anvil.
Motion control components, vane and piston motors, high pressure hydraulic valves, cylinders and electro-hydraulic controls are just a few of the products now manufactured by Eaton under the Vickers standard. Once among the most esteemed names in engineering, Vickers ceased to exist as an independent company in 1999, when it was bought up by Rolls Royce, and was in turn cut up and sold to various other corporations.
Eaton Vickers products have made their way into homes, factories, aircraft, ships and machines across the globe. Aside from its manufacturing history, Vickers is also known for having produced the first fluid analysis laboratory in the industry, where the specialized liquids used in the company’s high pressure hydraulic valves are still tested and perfected.
These days, though, a legion of younger, perhaps more hungry (and hence more volatile) companies have sprung up, all looking to dominate and outstrip competitors with the quality of their heavy duty piston motors, LSHT (Low Speed, High Torque) vane motors, high pressure hydraulic valves, directional valves and piston pumps. Dynex is one such company, specializing in heavy duty and split-flow pumps, some of which are rated for pressures as high as 20 000 PSI.
It is truly almost impossible to compete with the strength of corporations that have been around since an industry began. Ultimately, there are some companies that you either work with, or fall to. Parker Hannifin is one such company. Through a long genealogy of mergers and acquisitions, the company can trace its origins to Denison hydraulics, the company originally founded as The Cook Motor Co in 1900. At the time of its inception that company was a manufacturer of heavy duty industrial gasoline engines for locomotives.
After World War I, the locomotive engine met the demise of profitability, and Denison called for his son Bill to take over the company. And so it was, in 1925, that the young man conceived of a design for the first hydraulic machine – a humble device designed to push carts full of clay through a kiln at an adjustable speed. It was the dawn of an era, and it’s an era Parker has an uncontested place in. The company is to this day know as a manufacturer of the finest high pressure hydraulic valves, and its throne is one that’s unlikely to be toppled for some time to come.
