Get your filtration to-go

Donaldson’s new filter cart

Donaldson’s new filter cart not only removes solid contaminants from hydraulic fluid, but an optional water-absorbing element removes water as well.

More and more system designers and plant engineers recognize that off-line filtration provides an effective and cost-effective means of achieving and maintaining cleaner hydraulic fluid. Off-line filtration, often referred to as a kidney loop, draws fluid from a reservoir, pumps it through a filter, and returns the clean fluid back to the reservoir.

This fluid cleaning process can occur continuously or whenever fluid contamination exceeds a predetermined threshold. Furthermore, it can be performed when equipment is running or idle, so the hydraulic system need not be shut down to change dirty filers. The filters operate at maximum efficiency because fluid is pumped through them at a constant flow rate, rather than at a wide range of flows if they are part of the hydraulic system itself. Because it is so effective at removing large amounts of contaminants from a hydraulic system, many consider it to be the most cost effective method of filtration.

But you can get even more bang for your filtration buck by sharing an offline system among multiple hydraulic systems. This is easily accomplished with a filtration cart — essentially a portable, self-contained off-line filtration system complete with fluid lines, quickacting couplings, filters, and motor.

The newest filter cart to hit the market comes from Donaldson Co., Minneapolis, and it provides a convenient and effective method of off-line filtration, flushing, and fluid transfer for in-plant machinery and hydraulic equipment. Donaldson’s filter cart includes two in-series pressure filters that remove solid contaminants. In addition, a water-absorbing element may be installed to further remove particulate matter and water. Its 1-hp motor, coupled with a 10-gpm pump, provides efficient fluid transfer and filtration.

Industrial manufacturers will see the immediate benefits of this hydraulic filtration solution in a variety of applications, such as:

  • filtering new fluids that usually fall above the recommended ISO cleanli- Get your filtration to-go ness levels,
  • supplementing existing filtration,
  • transferring fluids from a drum or other storage container to a machine's reservoir,
  • removing free water from previously filtered fluid,
  • thoroughly flushing machines after service, repair, or rebuild, and
  • eliminating debris and dirt accumulated during fabrication, storage, and transport of new systems.

The Donaldson filter cart contains a safety relieve valve to prevent over pressurization, which could otherwise damage the cart’s pump, hoses, and filters. An overload protected switch prevents the unit from overheating. Convenience features include a rearmounted motor for balance, a removable angled drip tray, and clear braided hoses for viewing fluid.

For information about Donaldson products for industrial hydraulic applications, visit, where you can download a complete brochure.