Introduction
Since most industries require machinery to function at elevated temperatures, high-temperature lubrication and greasing demand is growing tremendously.
High-temperature greases are top-performing, versatile lithium complex greases produced using an optimised amalgamation of top-notch mineral oil, specialised thickener engineering technology, and an extensively preferred additive mechanism. When introduced with various operational load conditions, velocities, and climatic circumstances, high-temperature greases deliver sustainable performance over a broad temperature range.
Also, with so many factors that come into play, including oil type & viscosity index, additive composition and properties, thickener type, ambient & operating temperature, etc., it gets crucial to select the ideal grease for high-temp applications.
What are the Top Characteristics and Benefits of High-Temperature Greases?
High-temperature greases show:
- High thermal and mechanical stability
- No lacquer formation or coking observed
- High load resistance and low evaporation
Some of the essential characteristics are:
Dropping point
The dropping point is a measure of a grease’s heat resistance and the maximum temperature limit at which it holds its composition. The thickener used is infusible or has a higher dropping point.
Oxidation resistance
A grease can endure a chemical reaction with oxygen. Base oils exhibit strong oxidation resistance.
Pumpability
Pumpability is the convenience with which a pressured grease can stream through grease-dispensing system lines, nozzles, and fittings. High-temperature greases show great pumpability.
Water resistance
Grease can tolerate the impacts of water while maintaining its propensity to lubricate. High-temperature greases have outstanding lubricity and water-wash resistance even in harsh environmental conditions.
Top Five Critical Benefits of High-Temperature Grease for Industrial Use
- Exceptional mechanical and thermal endurance ensures product reliability and quality control across a broader operating temperature range, allowing prolonged relubrication cycles and lower maintenance.
- Excellent extreme pressure and anti-wear characteristics offer extended component life.
- Superior water resistance offers additional protection in applications where leakage and degradation are more likely.
- Excellent corrosion resistance when grease-lubricated bearings are subjected to a spectrum of controlled wet conditions.
- Excellent multifunctional capabilities, allowing for a reduction in product inventory
What are the Most Significant Properties of High-temperature Grease?
Some of the top-quality high-temperature greases exhibit the following functional properties:
- Due to its viscosity, HT grease works as a sealant to inhibit lubricant leakage and entry of corrosive pollutants and foreign elements. It also shows exceptional seal compatibility.
- Because of its rigidity, HT grease can be contained easily using simpler, less expensive retention mechanisms.
- When blended for high service or exceptionally high applications, HT grease holds solid lubricants in suspension.
- It is not necessary to control and monitor the fluid level
How to Select High-Temperature Greases?
The long-term performance of the grease is governed by degradation factors, including- mechanical (shear and stress), oxidative, and thermal stability. Thus evaluating the following HT grease constituents is critical:
Base oils
The most common base oil component is mineral oils. Understanding the base oil’s performance characteristics and its degradation parameters is critical. Only then can the high-temperature grease manufacturers in India choose materials based on their acquaintance with and maybe the availability of the resources.
Thickeners
Lithium complex-thickened grease provides greater thermal deterioration limits and has higher maximum temperature boundaries than other thickening agents and materials.
Additives
Grease additives offer features similar to other industrial lubrication products, such as oxidation stability, resistance to corrosion, fatigue strength, moisture resistance, etc. The additive must be able to interface symbiotically with the thickener and the oil to produce a homogeneous, stable blend of the three constituents.
Compatibility Among the High-Temperature Grease Constituents
Grease thinning indicates a lack of compatibility. At different temperature ranges & time limits, thickeners, additives, and base oils may all have complications.
Thus, before converting critical systems to a new grease, extensive testing is required to avoid substantial cost and time delays due to prolonged maintenance issues.
Five Steps to Follow While Selecting a High-Temperature Grease
- Evaluate the accurate temperature range. The operating temperature could be lower than the optimal range. To determine the working temperature of the grease, utilise a contact or non-contact sensor.
- Determine whether the requirement for grease is infrequent or continuous. If it is continuous, seek a high-quality product that fits the operating demands.
- Verify that the cooling and heating cycles coincide with the operating and non-operating cycles of the machinery.
- If relubrication is expected to be problematic, select a high-performance product, even if it is more costly, to obtain a reduced utilisation cost.
- Take into account any aesthetic concerns. Check to see if the product has dripped onto a component in the process. The volume and relubrication frequency needs to be calibrated against the risk of product degradation.
Conclusion
Choosing a high-temperature grease for single or multiple industrial applications could be daunting. The Castrol High Temperature Grease – Tribol & MolubAlloy series is unquestionably a top-quality option. It is engineered to meet environmental concerns, resist rust and oxidation, and provide long-term performance with low volatility and intermittent exposure to temperatures as high as 343°C/650°F.
