Polybutenes have several advantages over mineral oils when used in metalworking fluids
A metalworking fluid is used to maintain a protective film between the die or tool and the metal billet (a length of metal with a round or square cross section, created by continuous casting or extrusion). Such a film acts to reduce the frictional heat generated during the operation. The lubricant is expected to prolong the life of the die or tool, reduce energy requirements, and produce a smooth, stain-free surface of the metal article.
- High viscosity oils are preferred as the loads increase.
- In severe operations, an extreme pressure additive needs to be added.
In certain nonferrous metalworking applications, polybutenes have several advantages over mineral oils when used as a lubricant.
Properties
- PIB is non-toxic therefore where applications (of which there are many) place the operator in close proximity to the metalworking machine, the health risks are reduced.
- PIB contains no sulphur no nitrogen species = no staining of the metal.
- PIB produces no carbon deposit after decomposition by depolymerisation at temp. > 300°C so no attack to the metal (brazing, welding, etc).
- PIB has a diverse viscosity range so covers all area of metal production viscosity oils.
- PIB has good storage capabilities therefore no biodegradation.
End User Applications
There are different process needs for metalworking fluids:
Polybutenes can also be used in stamping, grinding, pressing, foiling, anti-corrosion, forging, welding, casting and ironing.
The main purpose is always the lubrification quality together with the total decomposition after burning without residue.
Metal Cutting Fluids
Throughout the machining of metal components, a fluid is generally sprayed onto the cutting tool surface. The cutting fluid significantly improves the machining process enabling the mass production of components. The spraying and high speed cutting frequently atomize the fluid into minute droplets, creating a constant fog-like mist in the plant. Ambient mist in machining plants is a continuing environmental concern, mainly, its effect on the workers’ breathing zone air quality.
High molecular weight PIB is exceptionally effective in suppressing mist formation for straight mineral oil cutting fluids, without adverse effect on the quality of the machined part or on the fluid properties.
Metal Drawing Fluids
Tube drawing: polybutenes can be useful in tube drawing. At an annealing temperature of 550°C to 600°C used for copper tubing, the polybutene is removed quickly and completely from the surface of the metal.
Metal Rolling Fluids
In cold rolling of aluminium sheet or foil, a lubricant is used to reduce the friction between the rollers and the metal sheet.
Some manufacturers avoid the staining from the mineral oil used during the annealing of aluminium by replacing it partially or totally with polybutenes.
In hot rolling of aluminium sometimes the use of an emulsified lubricant based on polybutenes of higher viscosity as PolybutTM 200 can be used.
Oil leaks, based on polybutenes, that contaminate the rolling oil or metal sheet do not stain because they will decompose totally at annealing temperatures.