Hydraulic oil is used in various hydraulic systems to transmit power and lubricate moving parts. One common type of hydraulic oil is anti-wear hydraulic oil, which is specially formulated to provide a high level of protection against wear and tear on hydraulic
components.

There are many different brands and types of anti-wear hydraulic oil available on the market, and each may have its own unique set of properties and advantages. Some of the key characteristics of anti-wear hydraulic oil include:

  1. High viscosity index: Anti-wear hydraulic oil is typically formulated with a high viscosity index, which means that it maintains its viscosity over a wide range of temperatures. This helps to ensure that the oil provides adequate lubrication and protection even in extreme temperature conditions.
  2. Anti-wear additives: Anti-wear hydraulic oil contains additives that are specifically designed to reduce wear and tear on hydraulic components, such as pumps, valves, and cylinders. These additives form a protective film on metal surfaces that helps to
    prevent metal-to-metal contact and reduce friction.
  3. Rust and corrosion inhibitors: Anti-wear hydraulic oil also contains additives that help to protect hydraulic components against rust and corrosion, which can cause damage and reduce the lifespan of the equipment.
  4. Foam inhibitors: Anti-wear hydraulic oil is also formulated with foam inhibitors that help to reduce the formation of foam, which can cause cavitation and reduce the effectiveness of the hydraulic system.
    Overall, anti-wear hydraulic oil is an important component in many hydraulic systems, and it is essential to choose the right type of oil for the specific application to ensure optimal performance and long-term reliability.

IS 11656 is an Indian Standard specification for hydraulic fluids. It covers several grades of hydraulic oil, including:

  1. Grade HM: This grade of hydraulic oil is formulated for use in hydraulic systems that operate at high pressures and temperatures. It has a high viscosity index and good anti-wear properties.
  2. Grade HLP: This grade of hydraulic oil is formulated for use in hydraulic systems that operate under moderate conditions of pressure and temperature. It has good anti-wear properties and good resistance to oxidation.
  3. Grade HVLP: This grade of hydraulic oil is formulated for use in hydraulic systems that operate under high-pressure conditions. It has a high viscosity index and good anti-wear properties.
  4. Grade HV: This grade of hydraulic oil is formulated for use in hydraulic systems that operate under high-pressure conditions. It has a high viscosity index and good anti-wear properties.
  5. Grade HEES: This grade of hydraulic oil is formulated for use in environmentally sensitive areas. It is biodegradable and non-toxic.
  6. Grade HETG: This grade of hydraulic oil is formulated for use in hydraulic systems that require biodegradable fluids. It is made from synthetic esters and has good anti-wear properties.
  7. Grade HFD: This grade of hydraulic oil is formulated for use in hydraulic systems that require fire-resistant fluids. It is typically made from water and glycols or water and esters. These are some of the common grades of hydraulic oil covered under IS 11656, but the specification also includes other grades that may be used in specific applications.

Here is a tabular technical data sheet for hydraulic oil grades ISO VG 32, ISO VG 46, ISO VG 68, and ISO VG 100 conforming to IS-11656

PropertiesISO VG32ISO VG36ISO VG68ISO VG100
Kinematic Viscosity (cSt) at 40°C32 4668100
Kinematic Viscosity (cSt) at 100°C5.06.88.811.0
Viscosity Index95100100100
Flash Point (°C)190220235250
Pour Point (°C)-30-27-24-15
Density (kg/m³) at 15°C870880890900
ColorAmberAmberAmberAmber

Note: The values given in the table are typical and may vary depending on the manufacturer and the specific product.