Roll Cladding - Ideal Characteristics
It is often helpful to review the general requirements of steel plant rollers, without delving too deeply into detailed theories, so very briefly, the rollers are required to:

• Support the slab through all sections of the caster, from the top zones were the strand is very hot and malleable to the straightner segments where the loads are high.
• Maintain a uniform slab cross-section.
• Hold a uniform size with neighbouring rollers to prevent pulling or pushing effects, and to maintain a uniform casting radius.
• Provide the traction effort to the strand.
• Straighten a curved strand (or bend a straight strand).
• Carry out all these functions in an environment of water sprays, high temperature and scaling, for as long a life cycle as possible, and with a minimum of maintenance.

Therefore the ideal roll cladding material will embody all the following attributes:

• High strength at elevated temperatures - for example, slab loads of around 50 tonnes at  900/1000 C.
• Resistance to thermal fatigue - wear surface cycles from say 650 C to 20 C.
• High wear resistance.
• Good corrosion resistance.
• Low cost of material and manufacture.

Welding Consumables - Bespoke Design
Selecting the material for surfacing, whether for the manufacture of new rolls, or the reclamation of existing rolls, obviously requires some thought. Apart from the performance requirements outlined above, attention has to be paid to the weldability of the material. And it is this philosophy that Corewire's engineers apply when designing our consumables; what are the specific operating issues, and which solutions can best be applied?

Roller Service Lives Increase - Reducing Maintenance & Operating Costs
As testimony to the success of this approach, there are currently over 250,000 such rollers welded with Weldclad consumables operating around the world. Indeed, millions of tonnes of various products have rolled over Weldclad welded rollers; but simple tonnage figures do not tell the whole story. Improvements in the roller's surface finish lead to equivalent improvements in product's surface. Reduction in roll wear means reduced roll changes and reduced adjustment. No cracking means better a better product finish and limited roll in-service failures.

Even those rollers which have produced the highest tonnage's are still in service, proving the reliability and durability of the Weldclad materials, and the technology by which those materials are applied. Overall, an improved roller means an improved product, and fewer problems for the maintenance crew means improved machine availability.

Examples of weldclad consumables in service are give in the Case Studies page.