Hydraulic oil viscosity chart iso#
APPLICATIONS Chevron Hydraulic Oils AW are versatile lubricants available in ISO viscosity grades 32, 46 and 68.
Moving forward in Repsol's commitment with sustainable development, this product range complies with the waste management hierarchy and is the link that completes the ecological chain of manufacturing, use, collection and recovery of used oils. hydraulic pressures increase over 1000 psi, the need for antiwear protection increases proportionally. These tractors require a trans-hydraulic fluid. To plot this kinematic viscosity of the fluid at 40☌ and 100☌ is necessary. Based on the ASTM D341 standard viscosity-temperature chart of all the fluids is plotted by using matlab program. In most modern tractors, especially those built after 1980, the hydraulics and transmission draw fluid from the same reservoir. Viscosity temperature chart The viscosity temperature chart is very useful to find the kinematic viscosity of the fluid at any temperature. This ensures that one brands 30-weight oil is the same viscosity as anothers. These new oils, in addition to being environmentally friendly, offer the same quality as any other HLP category lubricant on the market. ISO and SAE are standardized specifications that define oil weight. They are manufactured from a mixture of selected mineral bases and high-quality regenerated bases, carefully treated and purified, and specific additives have been selected to enhance their anti-wear properties. However, these fluids become highly viscous below –20° C.The lubricants of this range are specially designed for use in hydraulic circuits requiring fluids with anti-wear properties. For higher operating temperature applications, fire resistant synthetic hydraulic fluids are more suitable. In general, a viscosity grade 32 oil has a viscosity of about 150 SUS (32 cSt) 100 ☏, grade 46 - 200 SUS (43 cSt) 100 ☏, and grade 68 - 300 SUS (65 cSt. For hydraulic systems working under operating temperature range –40 to 100° C with a maximum temperature range –54 to 135° C, mineral based hydraulic fluids are preferable. Before referring to these charts, however, it is necessary to look at the listing of approved oils to determine if your intended hydraulic media is ISO viscosity grade 32, 46 or 68. Large high power level systems operating in relatively warm ambient temperature regions may require heat exchangers in order to maintain fluid temperatures below upper limits of 135° C. Low power level systems (low pressure of 1,000 psi or less and low flow (of 5 gpm or less) generally do not require any special cooling equipment. However, this rise normally is dissipated as the fluid passes through the system. losses through orifices and tubing, the hydraulic fluid temperature rises by 7° F per 1,000 psi drop for each circuit. When a pressure drop occurs without external work resulting, i.e. For analytical purposes, the assumption of uniform temperature throughout a hydraulic circuit usually is quite accurate. But recent advances in VI improver technology means that mineral hydraulic oils with a shear-stable viscosity index in the 150 to 200 range are now commercially.
In control systems, compression of fluid provides a mass-spring condition that limits system response. At high temperatures, low fluid viscosity can cause internal leakage and slippage in pumps, actuators and valves.Ĭompressibility of a fluid increases with pressure and temperature and results in loss of volume output of pumps. Hydraulic system efficiencies are reduced by high fluid viscosity at lower temperatures, which results in inlet problems with pumps, sluggish response of critical actuators, power loss in transmission and weight penalties due to line size. Where ambient and structural temperatures are above hydraulic fluid flash and/or fire points in a compartment, the potential fire hazard must be considered.įluid stability is affected by thermal stress, which can result in changes in viscosity and formation of volatile components, insoluble materials and corrosive deposits. Hydraulic fluid selection criteria include the expected range of operating temperatures, available means of temperature control and fluid physical properties at expected temperature levels.