More in Hydraulic Valves

I am not going to lie; this series of symbol and schematic based issues has been challenging to create. I still work full time here at The Fluid Power House, designing and selling hydraulic systems, sending technicians out on service calls and quarterbacking pump rebuilds, etc. On top of work duties, I also have three children under the age of four, so many of my evenings involve t-ball games, bottle feeds and sticky messes....More

In support of the growing trend towards using hydraulic fan drive systems, Comatrol, a member of the Sauer‐Danfoss Group, released two new product lines at Bauma China — RFDE reversing fan drive HICs and directional control valves. Comatrol said the new product lines are a continuation of its focus on high flow directional controls in 2012, and its continued investments in fan drive solutions for efficiently controlling the speed and reversing functions of hydraulic fan systems....More

Closed-loop electronic control systems exhibit the cutting edge of mobile electrohydraulics. But their price tag is prohibitively high for applications that don’t require such high precision and  intelligent control. An example is the CV 2000 load-sensing, post-compensated sectional control valve from Nimco AB, Malmö, Sweden. The CV 2000 LS can be used in systems with both fixed and variable displacement pumps. The compensators in the sections allow all functions to work even when the pump is saturated....More

PVG 16 load-sensing valve is designed for the low-flow segment. It facilitates the integration of load-sensing system design and electrohydraulic actuator technology — bringing high productivity, lower total system costs and easier fulfillment of emissions and safety regulations. It is rated for a flow of up to 65 lpm [17.2 gpm] and work port pressure of up to 400 bar [5800 psi]. Municipal vehicles, agricultural equipment, small cranes and construction machinery are among the key applications....More

Precision check valves suit high pressure, harsh duty applications. Constructed entirely of NACE compliant, corrosion-resistant materials, they feature a durable MP35N poppet and seat and are designed for checked direction pressures up to 15,000 psi. They are available for forward and reverse flow directions in five sizes ranging from 0.125 to 0.500 in. in diameter. The Lee Co., (860) 399-6281, bit.ly/hp1012lee...More

A gold smelting plant couldn’t get the hydraulically operated ladle to tilt and pour molten gold into ingot molds. The hydraulic system for this part of the system had its pressure and return lines connected to a central supply. All the other functions supplied by this system worked well....More

A plating mill receives 6- to 8-ft wide coiled steel and chemically treats it with a process similar to galvanizing. The rolls have about a 4 to 6 ft OD and are unraveled like paper towels. The loose end of a sheet is fed into a pair of pinch rolls that directs the steel through several stations that wash, rinse, dry, and heat it. After it is coated and treated, the steel is then rolled back into 4- to 6-ft coils and shipped to automotive stamping plants. The complete mill can be a city block long....More

Hi-Q pressure relief valve accommodates high relief pressure and high flow rate in a compact package. It is capable of relief pressures to 5400 psid and flow rates more than 19 gpm. Side inlet flow reduces installation boss size and weight. The valve comes with cracking pressures from 1000 to 5400 psid.  It is designed for nominal system pressures to 5000 psi and system peak pressures up to 6750 psi.  Each is 100% inspected and tested. The Lee Co., (860) 399-6281, www.theleeco.com...More

Matching the performance characteristics of a servo or proportional valve to the performance needs of an application requires at least two major system design steps....More

As designers have learned more about the detriments of hydraulic fluid contamination, they’ve been incorporating techniques to keep dirt and moisture out of hydraulic systems. Reservoirs have been one of the most common points of entry for dirt and moisture. Fortunately, filter breathers that incorporate moisture-adsorbing desiccant provide a simple and inexpensive way to keep dirt and water out of reservoirs....More