The importance of high temperature lubricants

High temperature lubricants play a key role in maintaining the performance and durability of machinery operating under extreme heat conditions. These specialist lubricants are designed to withstand elevated temperatures without losing their lubricating properties, ensuring smooth operation and preventing costly equipment failures.

Lubricants must withstand high temperatures without chemically or physically evaporating or dispersing. They must also provide enough lubrication to protect unprotected parts and components from wear and friction.

Basic features of high temperature greases:

1. Thermal Stability : High temperature greases are formulated to resist thermal degradation, retaining their consistency and lubrication properties even at elevated temperatures.
2. Antioxidant properties : Contains additives that prevent oxidation, which can lead to harmful deposits and build-up in machinery.
3. Water resistance : Some high temperature greases are also water resistant, providing protection in humid or wet environments.

How to choose a high temperature grease?

When selecting a high-temperature grease, consider the following factors:

1. Determine the actual temperature range. Operating temperature may be lower than it appears. Use a contact or non-contact sensor to measure the operating temperature of the lubricant. Is it above 392ºF (200ºC)?
2. Is it intermittent or continuous? If it is continuous, look for a top-of-the-line product that meets operational requirements.
3. Do heating and cooling cycles accompany machine on and off periods? Consider whether moisture can be induced by the atmosphere or machine steam impacts
4. What is a reasonable relubrication interval or relubrication capability? If relubrication is going to be difficult, consider a top-of-the-line product for lower operating costs, even if it is more expensive.
5. Consider any cosmetic issues. Can product drip onto the part during the process? The frequency and volume of relubrication must be balanced against product contamination issues.

Types of high temperature greases :

• High Temperature Molybdenum and Graphite Grease : Used in bearings, trolley wheels, fans, film tensioner chains, etc.
• High temperature silicone grease : Resistant to the external environment.
• Copper grease : Often used in braking systems and industrial machine components.
• Perfluoropolyether (PFPE) oil based products : Used in the chemical industry, fuel and chemical tanks

By selecting the right high-temperature greases for specific applications, companies can improve equipment efficiency, reduce maintenance costs and increase overall productivity. With specially designed high-temperature greases, these problems can be solved.

Many of the advanced oils used in high temperature greases (fluorinated polyethers, perfluro polyethers, phenyl polyethers, silicones, etc.) will outlast their thickening systems.

High temperature synthetic greases

Synthetic greases are designed to withstand high temperatures and provide excellent lubrication, making them a popular choice in high-temperature equipment.

Synthetic oils have excellent high temperature oxidation resistance compared to conventional mineral oils and generally have better viscosity properties and film strength at high temperatures.

High temperature grease applications:

• Automotive : In wheel bearings, constant velocity joints and other components operating at high temperatures.
• Industry : In steelworks, foundries, furnaces and other industrial processes involving high heat.
• Aviation : In aircraft engines, landing gear and other critical components operating at extreme temperatures.

High temperature greases are often used to lubricate parts such as:

• Rolling mill bearings

• Molykote G-Rapid plus - grease, lubricating paste with molybdenum disulfide, Prevents fretting corrosion and rust, Wide operating temperature range (-35°C to 450°C)

• Crushing and screening machines

• Molykote Gn plus - black Molybdenum grease, Excellent solid lubricant Thermal stability (from -18°C to 399°C)

• Roller bearings for gluing, paper converting and drying machines

• Molykote 7348 high temperature silicone grease with lithium thickener and Teflon (PTFE) additives and antioxidants for long-term lubrication of rolling bearings operating at high temperatures (230°C and short-term up to 250°C). Due to its unique composition, the 7348 grease has a very long service life and lubricating capacity, low evaporation, high oxidation resistance, resistance to water washout, prevents stick-slip and can be used on wet surfaces and in very dusty conditions.

• Oven grates and fire rollers for ovens

• Molykote 41 - silicone grease for very high temperatures, mainly used at low speeds. It is used to lubricate ball bearings operating under light or moderate loads, operating at very high temperatures up to +290°C.

• Oven fan bearings

• Molykote 44 Medium - High Temperature Silicone Grease, Excellent oxidation resistance, Excellent compatibility with plastic surfaces. Robust temperature range (-40°C to 200°C)
• Molykote 7348 High-temperature silicone grease with lithium thickener and Teflon (PTFE) and antioxidant additives for long-term lubrication of rolling bearings operating at high temperatures (230°C and short-term up to 250°C).

• Hot mix asphalt plants

• Molykote G-Rapid plus - grease, lubricating paste with molybdenum disulfide, Prevents fretting corrosion and rust, Wide operating temperature range (-35°C to 450°C)
• Molykote 3451 - high temperature fluorosilicone grease working in the presence of chemicals and under heavy loads for bearings. The grease composition is based on fluorocarbon oil thickened with fluorinated polymer (PTFE). Particularly suitable for work in a harsh chemical environment, in the presence of acids and bases. Resistant from -40 to 232°C

• Conveyors, industrial painting lines

• Molykote 3451 - high temperature fluorosilicone grease working in the presence of chemicals and under heavy loads for bearings. The grease composition is based on fluorocarbon oil thickened with fluorinated polymer (PTFE). Particularly suitable for work in a harsh chemical environment, in the presence of acids and bases. Resistant from -40 to 232°C
• Molykote 3400 Heat cured anti-friction coating filled with molybdenum disulfide and antimony trioxide. Low temperature (C) -200, High temperature (C) 315

• Space Equipment (300 degree high temperature grease is preferred)

• Molykote HP 300 high temperature fluorinated grease provides exceptional properties under extreme conditions. HP 300 grease is resistant to chemical environments, used for high loads, vacuum and high pressure operations such as those occurring in semiconductor production. The grease is exceptionally stable at high temperatures, showing very good compatibility with elastomers and plastics. Resistant to temperatures in the range of -40 to 232°C
• Krytox™ GPL 226 Grease , High quality non-flammable grease approved for contact with oxygen, white, clean, non-toxic, non-reactive, Does not ignite spontaneously in oxygen at temperatures up to 482 ºC, resistant to constant temperatures -36– 260 °C
  

• Water pumps and electric motors

• Molykote 3451 - high temperature fluorosilicone grease working in the presence of chemicals and under heavy loads for bearings. The grease composition is based on fluorocarbon oil thickened with fluorinated polymer (PTFE). Particularly suitable for work in a harsh chemical environment, in the presence of acids and bases. Resistant from -40 to 232°C
• Molykote 44 Medium - High Temperature Silicone Grease, Excellent oxidation resistance, Excellent compatibility with plastic surfaces. Robust temperature range (-40°C to 200°C)
• Molykote 7348  High-temperature silicone grease with lithium thickener and Teflon (PTFE) and antioxidant additives for long-term lubrication of rolling bearings operating at high temperatures (230°C and short-term up to 250°C).