Hydraulic Pilot Operated Check Valve

Designed for use in applications requiring an actuator to be locked in position, Pilot Operated Check Valves allow free flow from the input port through the output port. Supplying a pilot pressure to the valve allows flow in the opposite direction.

Typically, there are two types of hydraulic pilot operated check valve. These are the line mounted type with integral or external oil pilot and the manifold type that can be mounted directly to a cylinder or a control valve. Most systems and users will find that these designs of valve work most effectively when in conjunction with a control valve, which allows the valve ports to vent to the tank once it has been centred.

If you would like more information on this and related products, our experienced sales team will be pleased to help. Please contact us on 01626 863634 or email sales@hypro.co.uk

For more technical information on these and other products please download our valve catalogue: https://www.hypro.co.uk/images/companies/1/HB0015_02_Valve_Catalogue_Sep_2018.pdf

British To the Core

With the uncertainties of Brexit and trade wars, there has been a pressing need for British self-sufficiency in engineering in the last couple of years.  Quality, supply problems and lack of local expertise have also been a problem in the past for smaller OEMs.  Recently, these problems have become even more of a threat with Coronavirus which is now threatening to cut supply chains across the globe.

Tim Wright Ltd, British manufacturers of post driving machinery since 1992, recognised the dangers of globalisation ten years ago.  Quality was an important issue for them as well as continuity of supply and they decided to source in the UK wherever possible.  “We even have our nuts and bolts made in Birmingham”, they proudly report.

Tim Wright, themselves manufacturing in Rocester, Staffordshire, produce a whole range of post drivers under the WRAG trademark.  Their range extends from small ones to fit 1.5-ton excavators to the self-propelled WRAGTRACK OPUS and bespoke machinery.

Mainly seen in the fencing, forestry and agricultural industries, WRAG post drivers are now also found in the construction, railway and highway sectors.  Their largest market is the UK and Europe, but they sell to other countries, including the USA and Australia.

The secret of their success is producing high-quality machinery.  This is due to a highly skilled workforce and close relationships with British suppliers, enabling them to have full control of their processes and components.  The hydraulic system is a key part of post driving machinery and British hydraulic control valve manufacturers are a rare breed.  However, they did find Hydraulic Projects Ltd who manufacture the Hy-Pro range of control valves in rural South Devon.  Hydraulic Projects, established in the 1960s by Dick Hammond (an engineer of the Tomorrow’s World and Raymond Baxter era) have been developing and manufacturing the well-known sectional valve for much of that time.  The V5-60, a 60-litre valve is now produced on the latest CNC lights-out machinery in the factory in Dawlish and is the valve of choice for small to medium OEMs requiring robust quality solutions.  The team at Hy-Pro have in-depth knowledge of their in-house designed valves and their applications.  In addition, like Tim Wright, the Hy-Pro valves are machined and assembled by a skilled workforce on site.

The WRAG machines use 8, 9 and 10 lever V5-60 spool valves controlling the “set up functions” of the machines, giving precise positioning at the user’s fingertips.  The machines can operate within a 180-degree arc and they boast that “no awkward corner is impossible”. The hammer function accelerates the weight, exploiting the high capacity tank galleries, offering very little resistance to the oil flow.  This allows the weight to fall quickly, which is important in a post driver.

Whilst there are foreign monoblock options, they are often unsuited to complex applications from a single oil supply.  In contrast, the V5-60 sectional valve can be assembled in any configuration.  The Hy-Pro valve is particularly suitable to the WRAG installation because of its oversize internal oil galleries, coupled with the extensive range of ancillary elements offered as standard.  The most important virtues of the Hy-Pro valve are that is readily available on short lead times and comes with direct support of the design and manufacturing team here in the UK.