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News You Can Use: Issue 8

"Unparalleled Delivery Times on Custom and Standard Filtration Products”

Partner with Us to Help Your Customers Solve Their Problems!

In the today’s global markets, manufacturers have difficulty serving markets directly, and therefore rely on distributors to handle distribution, whether domestic or abroad. Distributors also fill roles for consumers as a source for products they need. We at OFCO understand the importance of getting our products to those who need them and we honor our relationship with our distributors as our salespeople in the field. We are always looking for new distributor/partners who would like to grow with a manufacturer that has been manufacturing filters, strainers, and custom filter products for over 75 years. Click here to learn more.

OEM Mobile Heavy Equipment Filters

OFCO has a listing of replacement filters and strainers for large OEM heavy equipment. Give us a call to see if we can help you in your quest for additional business. We can interchange filters and strainers for…

Allis Chalmers
Caterpillar
Daewoo
Clark
Euclid-Hitachi
Ingersol Rand
J.I. Case
John Deere
Nacco
Terex
Yale
Hyster
Mitsubishi
New Holland
… and others

For the Die-Hard Fans of Vocabulary Quizzes!

1. __________ __________ is the use of liquids or gases under pressure to move objects
or perform other tasks.

2. _____________________ is a force on a unit surface area (such as a square inch).

3. __________ __________ states that when a force is applied to a confined liquid,
the resulting pressure is transmitted unchanged to all parts of the liquid.

4. __________ __________ states that as pressure increases, the volume of the gas decreases.

5. __________ __________ are fluid power systems based on the use of air or another gas.

See answers at the bottom

A Simplified Study in Filtration

Part 5 of 10

Two Locations in the Hydraulic System Some Sort of Filtration Should be Installed

Last time we mentioned how the reservoir could be considered a filter itself. Now let’s take a look at the first two locations in the hydraulic system where some sort of filtration should be installed.

The absolute first area in which a filtration device should be installed is on the inlet (suction) line before the pump. These strainers are used to prevent ingestion of large particles into the pump. Before we go any further, I need to make a very important point. It is very important to keep the pump operating in a smooth and efficient manner. Remember, the pump is the heart of all hydraulic systems. It is the most important component. The pump can be considered just like the human heart. If the human heart stops or breaks down, what occurs? The human body breaks down or stops. The same applies to the pump in a hydraulic system. If the pump stops, the system stops. 

The suction strainer could be a strainer placed on the end of the inlet line at the bottom of the reservoir, installed through the side wall of a reservoir, or an “in-line” type placed between the reservoir and the pump. Keep in mind that this is an area where, most of the time, “straining” should occur and not “filtering.” I suggest no finer filtration than 74 microns (200 mesh). With low pressure vane or gear pumps, a 149 micron strainer should be adequate. With piston pumps and/or high-pressure systems, a 74 micron strainer should work fine. 

If there is too fine of filtration on the inlet line, the pump could possibly cavitate, leading to components being damaged or destroyed. For that reason, it is important to have a by-pass valve on your inlet strainer. That will take care of any possibility of cavitating the pump.

Another reason for using a bypass is during cold weather start-ups. Using a bypass will allow unfiltered fluid to bypass the strainer and continue through the system until its viscosity reaches standard operating temperature. Allowing unfiltered fluid to temporarily bypass the strainer can be more cost effective than possibly collapsing the strainer or destroying a pump due to cavitation. However, I cannot stress enough how important regular system maintenance is to maintain clean fluid running smoothly through the pump.

The second location a filter should be placed is in the pressure line following the pump and before the actuation, the component that is actually performing the function. If a directional valve is used, install the filter before the directional valve. The actuation performs the work of the system and has the greatest need for the finest filtration. Pumps produce wear and debris. If you have a servo system, the micron rating on this filter should be 3 microns or finer. At this stage of the system you want to insure the filter is as fine as the application requires. The question is not, “How clean does the fluid have to be?” The question is, “How dirty can the fluid be to still get the job done and still give you good system life?” In a “typical” hydraulic system, if there is such a thing, a 5-10 micron cellulose paper or glass filter is adequate. 

We merely touched the surface with the first two areas where a filtration device should be installed. Stay tuned for the 3rd and 4th areas.

Vocabulary Quiz Answers1. Fluid Power; 2. Pressure; 3. Pascal’s Principle; 4. Boyle’s Law; 5. Pneumatic Systems