On the basis of our standardized programme our rolls are a concept of quality. Since many years they have proved to be efficient and reliable tools all over the world.
In addition to this standard quality programme further individually adapted grades are at your disposal to solve special rolling problems.
Careful investigations on the parameters given by our customers, combined with our vast experience and specific influences on the roll materials, often lead to improved solutions.
If you require our advice in this regard please contact us or send us a description of your problem, including information about your current roll quality and the rolling and cooling conditions in your mill.
The synthesis of the practice of the rolling mill personnel and the knowledge of the roll-foundry engineer often leads to a better result.
To assist you with advice, is our strong point.
It would be a pleasure for us to have discussions with you and exchange experiences.
Rolls for flat steel products
Our aim is to find a roll which gives the best possible compromise between mechanical wear resistance and thermal fatigue stregth which is necessary to withstand the maximum rolling pressure.
In this regard the cooling conditions have a fundamental influence on the above mentioned parameters.
According to physical laws all these components oppose each other - but it is worth while to look for the optimum solution for your individual conditions.
Mecanical values and properties
During rolling the roll material is subject to a very complex load in the contact zone with the rolling stock and in the following cooling phase. The most important types of strain having effect on the roll material are :
- Tensile and pressure forces and the resulting shearing strains below the roll surface
- Changes in temperature which can lead to fire cracks
- Friction
- Oxidation
- Abrasion
Besides the mechanical, physical and chemical properties of the roll materials the process technology and the parameters in the mill are decisive for the roll's performance (tonnage, profile durability, surface of the rolling stock).
In order to provide a comparative outline the table/diagram contains the tensile strength of the roll materials in the working layer.
The working layer is stressed by the rolling process, whereas the necks and the core of the roll are stressed by the driving torque and the bending load (especially in 2-high stands).
Karl Buch has been certified according to EN ISO 9002. Our rolls are controlled by specially trained inspectors. If requested, inspection reports will be supplied together with full dimensional documents confirming the known precision of our rolls.
Section mill rolls
The question is to find a roll which gives the best possible compromise between mechanical wear resistance and thermal fatigue strength considering the material strength which is necessary to withstand the maximum rolling pressure.
In this regard the cooling conditions have a fundamental influence on the above mentioned parameters.
According to physical laws all these components oppose each other - but it is worth while to look for the optimum solution for your individual conditions.
Cast and heat treated
Thanks to long experience and continuous investigation Karl Buch disposes of carefully directed melting and casting technics.
In the compound process (statical and centrifugal) the hard carbide containing shell materials are combined with a soft grey cast iron or nodular cast iron core in molten condition. The result is a highly wear-resistant roll with good strength properties in the core.
In the centrifugal casting process the shell and core materials are stratified into one another symmetrical to rotation - the ideal basis as well for the exact thickness of the working layer as also for the thermal stability of shape and concentricity.
Individual heat treatment guarantees the correct state of matrix and tensions for a balanced mechanical and thermal behaviour of the rolls.
The security of our section mill rolls is appreciated by our customers all over the world.
Machined and inspected
The course of production is supervised by specially trained and experienced inspectors according to DIN ISO 9000, 9002 and 9004.
If requested, for your assurance inspection reports will be supplied with our rolls; if required, in addition we can give also full dimensional documents, both of which confirm the known precision of our rolls.
Rolls for the Rubber and Plastics Industries
1. As hollow casting, barrel and necks internally bored for uniform wall thickness.
2. As solid casting, statically cast or centrifugally cast, peripherically drilled, with all types and designs of circulation and tightening systems for all heating or cooling. Plugs and rings of various designs are available.
3. Special designs, for example statically cast roll bodies or centrifugally cast shells with steel journals or shafts, bolted, shrunk-fit or glued.
Alloyed Chilled Cast Iron Rolls and especially Chromium Cast Steel Rolls offer an increased resistance to corrosion and abrasive wear.
Many years of experience enable Karl Buch to utilize highly developed casting procedures, especially when centrifugal casting the shell and core layers are cast absolutely symmetrical to rotation - the ideal basis for thermal stability of shape and cylindricity. Individual heat treatment guarantees the correct state of stresses for optimal thermal behaviour of the Calender Rolls; relied upon by our clients all over the world.
Our experience enables us to grind your rolls cold or hot at your individual operating temperature, finishing your Chilled Cast Iron or High Chromium Rolls with cylindrical, convex or concave barrel shape to any finish desired by you. Together with our test certificates you receive our diagrams which guarantee the well known precision of our rolls. Rolls can also be finished Chrome-Plated. The finish can be polished or matted, whichever is the best suited to your product.
We manufacture Cracker and Mixing Mill Rolls with corrugated bodies with different groove configurations.
For new equipment, we can assist you, if required by your authorities, with the necessary official approval by the German TUV.
