STEEL INDUSTRY

Lubricants For Steel Industry

Continuous research for deploying efficient, reliable and environmentally safe technology has led to the deployment of special lubricants in steel manufacturing process. While break down costs are exponential, conditions in steel manufacturing process pose tribological challenges such as high process temperatures, corrosive cooling liquids, abrasive dust, devastating shock-loads etc. In such a scenario, the lubricant is primarily desired to act as protective film with high separation power, be inert to entraining process fluids, resist tribo-corrosion and maintain lubrication during high operating temperatures.

Some critical machinery in a steel processing unit where special lubricants play a pivotal role in functioning of the systems are the continuous caster unit, hot strip mill, thermo mechanically treated (TMT) bar mill and the run on table (ROT). Whilst work environment of these machine systems are almost similar with high temperatures, dusty environment and high water ingress, the lubrication technology to be employed requires careful consideration.

HOT STRIP MILL
BECHEM’s Highlub FA 67-400 and Highlub LT 2 EP developed in collaboration with German steel manufacturers and Academic community have helped reduce lubrication quantity for its customers by 50%, resulting in substantial cost savings.

CONTINUOUS CASTER
Spearheading the technology of large molecular poly-urea products, BECHEM has developed Berutox M21 KN for this demanding application.

WIRE ROD MILL
Operating conditions demand for greases with higher base oil viscosity and stable viscosity index to ensure a thick, high strength film between the contact surfaces.

RAW MATERIAL HANDLING SECTION
Selected grease for such heavy duty applications need to maintain its viscosity at bearing operating temperatures and should also be equipped with special additives to ensure a thick and stable film between contact surfaces under pressure.

INDURATING MACHINES AT SINTER AND PALLET PLANT
High loads with constant exposure to dust and high temperatures characterize operation of an indurating machine at Sinter and Pellet plant.

BECHEM for Integrated Steel Plant

Conditions in steel manufacturing process pose tribological challenges due to extreme process temperatures, presence of corrosive cooling liquids, abrasive dust, shock-loads etc. Therefore the operational environment on a lubricant is very demanding and severe. The lubricant is primarily desired to provide a strong protective film with high degree of separation, be inert to entraining process fluids, resist tribo-corrosion and withstand high operating temperatures.

While operational breakdown costs are exponential, the lubrication technology to be employed requires careful consideration. BECHEM’s Berutox, Highlub and Beruplex range of specialty lubricants have been developed in order to surpass the demands in virtually all critical applications of an integrated steel plant.

BECHEM’s customised solutions complemented with unparalleled service help customers achieve higher productivity levels by mitigating machine downtime and extending equipment life.

Benefits for your Application

  • Excellent consistency/temperature properties
  • High corrosion protection
  • Very good water resistance
  • Very good wear protection
  • Excellent pumpability
  • Minimising of friction and wear
  • Wide service temperature range
  • Increased base oil viscosity
  • Extreme pressure properties

FREQUENTLY ASKED QUESTIONS

Greases are made by mixing a solid material, called a thickener, with a base oil and property enhancing additives; but it’s the oil that forms the lubrication film. For better understanding, grease thickener can be thought of as a sponge saturated with oil. Moving parts squeeze the oil out of the sponge like thickener for forming the lubrication film. Typically, the base oil constitutes the largest proportion of grease weight at about 80-90%, followed by thickener at 10 to 20% and additives under 10%.

Dropping point of a lubricating grease is an indicator of the heat resistance of the grease. and is the temperature at which the grease is no more a thickened lubricating medium. The dropping point indicates the upper temperature limit at which a grease retains its structure, not the maximum temperature at which a grease may be used.

Few greases have the ability to regain their original structure after cooling down from the dropping point.

The most important feature of a grease is its consistency. A grease that is too stiff may not get pumped into areas requiring lubrication. While a grease that is too fluid may leak out. Grease consistency depends on the type and amount of thickener used and the viscosity of its base oil. A grease consistency is its resistance to deformation by an applied force.

The measure of consistency is called penetration. Penetration depends on whether the consistency has been altered by working. Standard test procedures established by American Society for Testing and Materials International (ASTM) and accepted by industry are ASTM D 217 and D 1403, measure penetration of unworked and worked greases.

The NLGI has established consistency numbers ranging from 000 to 6, corresponding to specified ranges of penetration distance of the standard cone into the test grease. Table below lists the NLGI grease classifications along with a description of the consistency of each classification.

Viscosity: It is a measure of resistance to flow of a lubricating oil.

Viscosity index: It is defined as rate of change of viscosity with respect to temperature.

Significance:

  • It is the most important property which determines the performance of lubricating oils under the influence of temperature
  • A lubricating oil should have sufficient viscosity to retain a lubricating film on the surface
  • On machine part moving at slow speeds under high pressures, a high viscous oil should be used as it better resists being squeezed out from between the rubbing parts.  Light oils can be used for lower pressures and high speeds.
  • It is not possible to maintain a liquid oil film between two moving or sliding surfaces if the viscosity is too low and hence excessive wear will occur.

The pour point of an oil is the minimum temperature at which the oil turns into semi solid and almost losses its flow characteristic. At low temperatures, the viscosity of the oil will be very high, causing the oil to resist flow. This is important in equipment that operates in a cold environment or handles cold fluids.