Hydraulic oil becomes cloudy when it is contaminated with water above its saturation level. That is the amount of water that can be dissolved in hydraulic oil and is typically 200 - 300 ppm for mineral hydraulic oil measured at 68°F (20°C).

Water in hydraulic fluid
● Reacts with some additives to form corrosive by-products which corrode some metals.
● Leaves critical surfaces vulnerable to wear and corrosion due to reduced lubrication film-strength.
● Clogs filters and reduces the filterability of the oil.
● Increases air entrainment.
● Increases cavitation occurrence.

Water removal methods
● Polymeric filters- H20 causes the polymer to swell, trapping water within the media. Best suited for removing small amounts of H20 or H20 contamination within allowable limits.
● Vacuum distillation - Water boils at 133°F (56°C) at 25 inches Hg. At this temperature water can be removed without damage to the oil or its additives.
● Headspace dehumidification- Circulating and dehumidifying air from the reservoir headspace causes water in the oil to migrate to the dry air. It is then removed by the dehumidifier.
● Changing out the oil - Depending on system size, changing the oil may be more cost-effective than using any of the above methods of water removal.

Prevention is the best cure and is cheaper than removing H20 from the oil.

Standard breather caps on hydraulic reservoirs are a major source of H20 in hydraulic power units. Replacing the standard breather cap with a hygroscopic breather will eliminate the moisture ingress and keep contamination particles out of the reservoir.

Pump Room HPS

Designed specifically to provide economical and easily maintained power sources for hydraulically powered machinery and test systems. Typical applications include

  • Laboratory and Test Lab HPS
  • Large flow central HPS systems
  • Used extensively where sound attenuation is not required

Tank-over-pump type construction with the hydraulic pump(s) bell housing mounted to an ODP electric motor, providing perfect alignment and facilitating replacement. System oil is stored in an overhead reservoir that provides a positive suction head to the inlet of the pump(s). The reservoir is over sized and contains baffling and return line diffusers to allow dissipation of entrained air. All possible connections, including components, utilize o-ring fittings or welded joints to eliminate external oil leaks. Standard input power is 460 VAC, 3 phase, 60 Hz.


Pump Room HPS.

Features

  • Easy Maintenance and Accessibility – Shutoff and check valves are provided on all lines to allow maintenance of the hydraulic power supply without excessive oil spillage. The reservoir has a full-size removable top for unrestricted accessand clean out.
  • Reduced Vibration – The pump-motor assembly is shock mounted below the reservoir and is soft connected by hoses to prevent mechanical excitation of the surrounding structure.
  • Ease of Installation – Power unit is skid mounted with full drip pan and drain. Forklift access or lifting eyes are provided on the unit for ease of handling.
  • High Capacity Water Cooling – A water flow modulating valve monitors reservoir temperature, limiting water flow to that required to maintain a set reservoir temperature. The heat exchanger is over-sized to minimize water consumption
    while dissipating full system heat load.
  • High Capacity Filtration System – Designed to achieve ISO 14/11 cleanliness level consistent with the protection of critical servo components, a full-flow filter with a 3-micron replaceable element is provided on the pump discharge.
  • Electric Motor Controls – Controls and motor starter are mounted in a NEMA 12 oil-tight enclosure located on the end of the unit. They include control power/emergency stop switch, main pump stop/start-low/high pressure switches, run-time hour meter, indicator lights for low oil level and oil over temperature.

Options

  • Optional Controls – Low oil pressure warning indicator, oil over temperature warning indicator, filter condition indicator(s) and optional combination fused disconnect.
  • Additional Filtration – Optional 3-micron, replaceable element return line filter or kidney loop filtration can be added.
  • Special Operating Conditions – Systems with operation to 550 degrees F (288 degrees C) and over 5,000 psi (345 bar) available.
  • Electrical Options – Other voltages and frequencies available.