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AKG AP Series

Kidney Loop in a Kit

Time and again, an offline filtration circuit has been regarded as perhaps the most effective filtration technique for the money to keep fluid clean in hydraulic and lubrication systems. Offline filtration—often called a kidney loop—works by drawing fluid from a hydraulic power unit’s reservoir, using a pump to circulate the fluid through a short filtration circuit, and returning the clean fluid back to the reservoir. What makes offline filtration especially effective is that it can work even when the system is powered down.

Furthermore, incorporating a heat exchanger within the circuit also reduces temperature of the fluid. High temperatures can quickly degrade hydraulic fluid and even produce byproducts that become particulate contamination in the fluid.

AKG Thermal Systems. Mebane, N.C., just made it easier to specify kidney loops for industrial hydraulic systems by introducing its AP Series of pre-engineered offline filtration circuits for industrial hydraulic systems. The kidney loop is not intended to be the only filter in a hydraulic system. And unlike return filter and other filters installed in the hydraulic system do not undergo flow surges and pressure spikes. That’s because offline filter circuits use a circulating pump that maintains a constant flow rate, providing constant fluid flow through the filter and heat exchanger for optimum performance.

The AP Series uses a single electric motor to drive the cooling fan and circulating pump. The unit incorporates a brazed-plate or brazed bar aluminum heat exchanger and comes in six sizes for flows from 11.3 to 18.7 gpm. Optional filters can .

AKG does offer a web-based online selection software program that will aid the selection of the correct product. Please follow the link for the program and tutorial video.

For additional information about AKG of America and its products, visit, call (919) 563-4871 or click here.

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