Undersized inlet hoses can cause cavitation damage in a pump. Undersized pressure hoses create restriction and increase neutral system pressure, which adds to system heat. Undersized return hoses can create restriction and damage the directional valve. All of these situations will increase maintenance costs by shortening component life.
Consider that the inside of a hose is not smooth. Internal friction is created as oil passes through, and friction equals heat. When possible, where there are long runs, consider steel hydraulic tubing in place of hose. Not only is friction reduced, but the tubing will help to dissipate heat. Also minimize the use of fittings — particularly 90° fittings — and keep hose runs as straight as possible.
The Forgotten Component
Oil has been described as the “forgotten component” in the hydraulic system. Yet, the life of every hydraulic component is directly affected by the choice and condition of the oil.
Follow the equipment manufacturer’s specification for the hydraulic oil in your equipment. Your local supplier can also recommend the best oil for your climate and operating environment.
Two major causes of hydraulic pump failure — contamination and heat — are preventable if the oil is properly maintained. Keeping oil clean by sampling and establishing a schedule for filter replacement, and cool by maintaining the proper level and keeping the reservoir clean, will substantially increase the life of the oil and every other component. ET