Akron Hydraulic Launches Service to Restore Control Valves

Akron Hydraulic, Akron, Ohio, has announced a new service that helps extend equipment life. The nationwide program aims to restore hydraulic directional control valves to like-new condition to save equipment owners replacement costs.

“In today's economy, equipment managers are looking to extend the life of their fleet and not spend a fortune doing it,” said Mitch Langford, service manager at Akron Hydraulic. “Most equipment managers start drawing the line on repairs and parts when the cost approaches 50 percent of the equipment's value. This percentage can be expected to go up as the economy slows and capital expenditures tighten.”

Control valves direct hydraulic pressure to where the operator needs it to go to do the job. These valves stop, start and direct fluid flow. Whenever a cylinder moves on an excavator boom or a hydraulic motor turns dozer tracks, control valves direct the speed and result of the work.

“Hydraulic pressure is a very powerful force, but it is not intelligent,'” Langford said. “Oil will always follow the path of least resistance. This is why the tolerances inside a control valve are so tight - up to 0.0005 inch, which is one-tenth the width of a human hair.”

Variable or fixed-displacement pumps generate the hydraulic fluid flow, and the flow resistance can sometimes be 3,500 psi or more in a piece of heavy equipment. The oil needs to be held back at these pressures by a metal-to-metal fit inside the control valve, and any scoring on the spool will create a path of lower resistance. Oil will leave the spool as opposed to doing work. This causes the valve to be sluggish, cylinders to drift and spools to leak.

Spools and cartridges begin to leak when contaminants enter the hydraulic fluid, which is nearly impossible to prevent in the harsh environments construction equipment typically works in. To keep the equipment productive, the compromised components must be either repaired or replaced. Replacement control valves can sometimes run as high as $25,000 or more, and lead times can be months. Akron Hydraulic's rebuilding process for control valves will restore them to like-new OEM performance for $600 to $900 per spool. For an eight-function valve, this can mean a savings of $20,000.

“The Akron Hydraulic rebuilding process is difficult and labor-intensive. It requires highly specialized machinery and machinists,” Langford said. “Our process starts with disassembling the valve and inspecting the parts. Then we'll ground off the hard chrome on scored spools and replace the chrome and use micro-grinding to restore tolerances. We then cut oil grooves back into the spool after hard chroming is completed.”

The cartridge or housing, if damaged, also goes through a similar micro-grinding process. Sometimes the spool needs to be rebuilt slightly larger if the cartridge needs to be honed. The valve is then reassembled with new seals, repainted and tested. Depending on complexity, this process takes three to four weeks, which is usually less than the lead time of a new valve.

This process can be beneficial on many types of valves, including closed-centered, open-centered, monoblock, stackable and sectional valves. The valves can have anywhere from one to 10 sections or spools. The Akron Hydraulic rebuild option is especially beneficial when valves are too costly to replace, the lead time from the factory is too long, or the valve is out of production.

Akron Hydraulic is working with companies across the U.S. and Canada to rebuild control valves. Budget quotes can be given over the phone or on the web with digital pictures and serial numbers, and hard quotes are given after the valve is disassembled. Valves are shipped to Akron, Ohio, and shipped back in three to four weeks. Akron Hydraulic stands behind all repairs with a 12-month, 1,500-hour warranty on parts and labor.

For more information about the rebuilding process or to get a budget quote, visit www.repaircontrolvalves.com.