Industry Requirements & Tribometry
We analyze the specific tribomechanical contact situations of your forming processes for the targeted design of boundary layer behavior.
Copper Tube Plants
The production of seamless copper tubes primarily takes place via the hot extrusion of cast copper billets (DHP copper) at temperatures between 750°C and 900°C. The billet is pressed through a die and over a mandrel using a hydraulic press. Friction in the die gap and on the mandrel bar is extremely high. After extrusion, the tubes are cold-drawn in drawing processes and finally soft-annealed in protective gas furnaces (nitrogen-hydrogen mixtures).
The greatest challenge in this process is the formation of carbonaceous residues (annealing stains) on the inner tube surfaces during the subsequent heat treatment. Residues of conventional mineral oil-based lubricants crack at high temperatures and diffuse into the copper structure. This negates the standard-compliant solderability according to DIN EN 1057. On the tooling side, the mandrel and die are subject to severe thermo-mechanical wear and material transfer (copper pick-up).
Process Requirements
Complete pyrolytic decomposition (TGA) at >350°C under protective gas without leaving solid decomposition products. Formation of thin, high-strength lubricating films under extreme contact pressures (up to 700 MPa) to prevent cold welding. Filler-free formulations to avoid solid entrapment in the soft copper surface.
Process Solution
Synthetic PROMET LUPRIT Syn-Wax melting waxes (ExtruTherm series) with optimized molecular chain structure for complete, ash-free and residue-free sublimation in the protective gas stream.
Economic OEE Benefits
- Up to 40% increase in mandrel service life due to wear-reducing separation
- Inner tube scrap rate due to annealing stains reduced to near zero
- Reliable compliance with surface energy requirements for capillary soldering (DIN EN 1057)
- Homogeneous press force curve due to stable sliding friction coefficient
Copper & Non-Ferrous Extrusion
The hot extrusion of solid and hollow profiles as well as rods from copper and copper alloys (such as brass, bronze, copper-nickel) takes place directly or indirectly on hydraulic extrusion presses at billet temperatures of 700°C to 1000°C.
Due to high frictional heat and the extreme tendency of copper to undergo adhesive wear, cold welding (copper pick-up) rapidly occurs at the edges of the dies and extrusion tooling made of warm-work steel (e.g. 1.2343/1.2344). This leads to scoring on the profile surface, geometrical deviations, and high scrap rates. Severe temperature cycles also cause thermal fatigue cracking (heat checks) in the tooling.
Process Requirements
Release agents must withstand extreme shear forces and press pressures >800 MPa in the forming channel. A high-temperature resistant, physical barrier is required between the tool and the alloy that does not release volatile pollutants, binds oxide layers (scale), and protects the die edges.
Process Solution
PROMET LUPRIT Extru-Lube / Graph-Lube formulations, PROMET LUPRIT BN-Shield boron nitride dispersions, and PROMET LUPRIT Stick-Lube lubricant sticks for maximum pressure and shear stability.
Economic OEE Benefits
- Significant extension of die service life by preventing copper pick-up
- Reduction of press force peaks during the cycle by up to 15% for protective equipment operation
- Optimization of profile surface roughness and defect prevention
- Prevention of metal entry and extrusion defects (back-end cracks)
Aluminium Permanent Mold Casting
Gravity and low-pressure permanent mold casting of aluminum lightweight components at molten temperatures of 700°C to 750°C requires heat-stable protective coatings on mold walls (dressings/lubricants) to protect the steel mold from molten erosion.
The incoming molten stream inflicts severe erosion on the mold tool and causes surface damage or sticking if separation performance is inadequate. At the same time, rapid cooling at the mold wall causes flow lines and cold run defects on the cast part. The mold coating must provide controlled thermal insulation to steer crystallization and offer high mechanical wear resistance.
Process Requirements
Excellent adhesion on cast iron and steel permanent molds at high temperatures, controlled thermal insulation, and zero gas formation on contact to prevent porosity in the casting.
Process Solution
Thermally curing graphite bonded coatings and aqueous dispersions such as PROMET LUPRIT GraphCoat / BN-Shield for permanent surface conditioning and insulation.
Economic OEE Benefits
- Increase in mold lifespan by protecting against thermal shock and melt erosion
- Smooth release performance without ejection delays or damage to castings
- Prevention of cold run defects and flow lines through tailored thermal isolation
- Superior surface quality and structural integrity of the cast components
Metal Forming
Cold, warm, and hot forming processes such as closed-die forging, extrusion, deep drawing, and stamping of steel, stainless steel, and non-ferrous metals subject tools to high cycle rates and extreme degrees of deformation.
High friction coefficients lead to excessive tooling wear (die washing, punch breakage) and cracks in the workpiece. A central B2B problem is subsequent component cleaning: lubricant residues must be completely removable in standard aqueous-alkaline degreasing baths before subsequent processing steps (such as electroplating, coating, or annealing).
Process Requirements
Formation of high-strength boundary films in mixed and boundary lubrication regions to prevent cracking during high deformation. Excellent wetting and adhesion characteristics on warm and cold metal surfaces, using clean, chlorine-free formulations.
Process Solution
Pressure-stable PROMET LUPRIT Draw-Lube ester oils, wax-based die lubricants, and PROMET LUPRIT Extru-Lube pastes for permanent separation and excellent washability.
Economic OEE Benefits
- Increase in stroke rate or drawing speed due to reduced frictional resistance
- Maximization of tool service life for punches and dies
- Complete aqueous-alkaline degreasability to prevent subsequent errors
- Compliance with modern occupational safety and REACH regulations
Foundry & High-Temperature Processes
Operating foundry machinery, melting furnaces, and processing metals at temperatures above 1000°C loads sliders, transport rollers, open gears, and furnace parts with extreme thermo-mechanical stress, scaling, and friction.
Conventional organic lubricants decompose immediately under these conditions, causing dry friction, heavy wear, scale formation, and structural seizing of fasteners and sliding elements. This causes severe mechanical down-times, extensive repair costs, and sudden shut-downs in B2B foundry environments.
Process Requirements
Release coatings must be fully stable against heat and oxidation, function as a physical scale barrier, and permanently prevent seizing/galling of sliding assemblies.
Process Solution
Inorganic barrier coatings from the PROMET LUPRIT PyroShield range, high-pressure graphite pastes (PROMET LUPRIT Graph-Lube), and visco-elastic bitumen films (PROMET LUPRIT BitumGuard).
Economic OEE Benefits
- Reliable galling prevention for hot bolts, guides, and threaded fasteners
- Minimization of unplanned down-times on melting and furnace machinery
- Reduced abrasive scale wear and maintenance of mechanical tolerances
- High adhesion prevents dripping, ensuring clean and safe operations
3 Steps to Tribological Approval
We analyze the tribomechanical load spectra of your extrusion and drawing plants for the targeted design of high-temperature-resistant release and sliding media.
Tribometric Parameter Intake
Recording of tool geometries, forming speeds, shear rates, and peak thermo-mechanical loads.
Practical Formulation
Optimizing melting profile, viscosity, and thermal behavior for residue-free evaporation under operating conditions.
On-Site Validation
Metrologically supported trial run to record surface quality and die lifespan limits.