New help in cleaning up your machines' hydraulic fluid.

To help you keep your molding-machine hydraulic fluids as clean as possible, a new diagnostic tool automatically checks contamination levels. The RC1000 system from Hycon Corp. of Bethlehem, Pa., not only lets molders monitor the condition of a press' hydraulic oil but also triggers filtration devices when necessary.

Not for every molding operation, the RC1000 mostly targets the needs of molders already sold on the benefits of off-line filtration as a preventive maintenance tactic. "Those who have already invested in filtration can use the RC1000 as a tool to identify potential contamination problems and take action in advance," says Hycon v.p. George Wilson. So far, Hycon reports that 10 such molding firms have incorporated an RC1000 into their maintenance strategy. And Wilson adds that Cincinnati Milacron's U.S. Plastics Machinery Div. in Batavia, Ohio, now uses an RC1000 to test new presses before shipping them to customers.

Assessing fluid cleanliness and then filtering as needed may improve quality and productivity by keeping machines running longer and more consistently. Wilson maintains that 70-90% of machine failures are rooted ultimately in fluid contamination problems. Also, clean hydraulic oil simply lasts longer and helps maintain longevity of filter elements as well, Wilson notes.

The need for filters has become more intense in recent years, Wilson says, due to the downsizing trend among press manufacturers. Smaller machines must operate at higher hydraulic pressure to do the same work as a larger press. And their smaller fluid reservoirs can boost contaminant concentrations.

Wilson adds that modern components, like servo valves, tend to have tighter operating tolerances and inherent sensitivity to contamination. "Today it's not uncommon for machine builders to install 3-, 5- or 10-micron filters in their machines' hydraulic systems," he says.

SEEING THE DIRT

The RC1000 system relies on an optical sensor to count and classify--by size only--the particles within a given volume of fluid. It then reports the results according to NAS or ISO scales, both of which characterize contaminant levels in terms of the number of particles of various sizes per 100 ml of fluid. The ISO scale, for instance, distinguishes between two types of particles, each carrying a different threat. "Silt" particles under 5 microns can shorten fluid life and threaten operating consistency, says Wilson. Particles bigger than 15 microns would ultimately cause "catastrophic equipment failure," he warns.

Beyond simply counting and classifying particles, the RC1000 interfaces with a variety of on- and off-line filtration devices in two different operating modes. One operating mode keeps a filter running until a preset degree of decontamination is reached, while the other mode maintains filtration within a selected band of contamination levels. The RC1000 has two relays to send a signal to the filtration device. And a menu screen on the control panel lets operators choose the desired filtration level and set time delays and other operating parameters.

Because the contamination sensor works at a flow rate and pressure far below those of an operating press, the system also includes a "conditioning unit," explains Wilson. The RC1000 has a valving system to reduce flow rates and pressures to levels the sensor can handle, enabling it to tackle operating pressures up to 5000 psi.

The stand-alone RC1000 stores the information from 300 tests and comes with a printer for tabular or graphic reports. But for keeping a plant-wide historical maintenance database, the RC1000 also comes with its own software package called RCDesk. Individual RC1000 units can be set up by the software, which runs on any IBM-compatible PC.

Though a single unit could be dedicated to one large or dirt-sensitive press, Wilson says most molders would opt for one RC1000 to serve the whole plant. As part of a preventive maintenance program, it would be used in conjunction with an off-line filtration device connected to a press' fluid reservoir.

A package consisting of the sensor, conditioning unit, printer, and software package costs $17,000.