MolaKule
Staff member
Subject: Hydraulic System and Fluid additives.
Setup: A hydraulic system has a 3 GPM pump that will be used to develop sufficient pressure to move an 8000 lb. load, using a cylinder with a round 10 Sq. inch piston face. So to move the load, the system pressure needs to be > or = 800 psi. However, at the end of piston travel when the load is no longer moving, the pressure will rise.
We want to keep the system pressure at or less than 1000 psi in order to not blow the seals in the various system components. Therefore, we will use a pressure 'relief' valve tapped into the high pressure line to keep the pressure from exceeding 1000 psi.
A spring in a simple hydraulic pressure 'relief' valve below uses its 'spring rate' to set the maximum pressure in the hydraulic system. When the system pressure gets to the 'cracking' point of about 998 psi, the pressure P will exceed the spring force and the cup (blue) will move to the right to allow fluid to be diverted back to the accumulator tank, thus keeping the pressure from exceeding 1000 psi.
Question: Due to the possibility of some moisture coming in through the breather and getting into the hydraulic fluid, we might be tempted to use a valve body and spring of stainless steel to avert corrosion and rusting.
But a standard steel spring and housing will suffice if we incorporate what additives into the base oil?
This question is open to all, but lets give it a day or two for non-engineering BITOG members to research the question and respond before the engineers pile-in.
Setup: A hydraulic system has a 3 GPM pump that will be used to develop sufficient pressure to move an 8000 lb. load, using a cylinder with a round 10 Sq. inch piston face. So to move the load, the system pressure needs to be > or = 800 psi. However, at the end of piston travel when the load is no longer moving, the pressure will rise.
We want to keep the system pressure at or less than 1000 psi in order to not blow the seals in the various system components. Therefore, we will use a pressure 'relief' valve tapped into the high pressure line to keep the pressure from exceeding 1000 psi.
A spring in a simple hydraulic pressure 'relief' valve below uses its 'spring rate' to set the maximum pressure in the hydraulic system. When the system pressure gets to the 'cracking' point of about 998 psi, the pressure P will exceed the spring force and the cup (blue) will move to the right to allow fluid to be diverted back to the accumulator tank, thus keeping the pressure from exceeding 1000 psi.
Question: Due to the possibility of some moisture coming in through the breather and getting into the hydraulic fluid, we might be tempted to use a valve body and spring of stainless steel to avert corrosion and rusting.
But a standard steel spring and housing will suffice if we incorporate what additives into the base oil?
This question is open to all, but lets give it a day or two for non-engineering BITOG members to research the question and respond before the engineers pile-in.
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