Supervisor: Professor P Nithiarasu and Dr Vladimir Bassbe
Sponsoring company: Tata Steel
During hot rolling of steel strip, scales can generate surface defects. Hydraulic descaling is utilised to remove scales, to prevent defects and ensure the quality of the final product. In general, three types of scales grow through hot rolling mill operations:
Primary Scale of 2-3mm thickness is formed during slab reheating and is subsequently removed in the first descaling operation. Secondary Scale is formed after the first descaling and grows fast in the roughing mill. Secondary scale is removed by high pressure water jets during the reversing roughing mill or before the strip enters the finishing mill.
Tertiary Scale is formed between the finishing mill descaler and the first finishing stand, between stands in the finishing strip mill and also after the stock exits the last stand of the finishing strip mill.
Inefficient removal of oxides during descaling operations and / or poor water spray cooling can result in thick tertiary scales, which in turn can generate surface defects during hot rolling.
Considerable research has been conducted relating hydraulic descaling to scale thickness, descaling systems, steel temperature, steel composition and scale morphology. However, there are knowledge gaps on how above combined process parameters coupled with water spray cooling and roll cooling influence surface quality.
The Research Engineer will: • Design an experiment to evaluate heat transfer between roll and steel during hot rolling. • Develop a method of measuring impinging pressure and cooling rate for spray nozzles; • Evaluate relationship between spray impact pressure and cooling rate; • Conduct hydraulic descaling experiments of primary and secondary scales; • Create models of: Temperature profile of the work roll (in each stand of seven finishing stands in the finishing strip mill in Port Talbot) and strip surface temperature. To include the effect of heat transfer coefficient at roll bite, strip temperature, water cooling, nozzle parameters, residual scale, tertiary scale, blistering of oxide films, strip speed, gauge and reductions; • Consider how outcomes might be utilised to support reduction of surface defects at Port Talbot.
Eligibility We welcome applications from candidates with an Engineering or Physical Science degree (minimum level 2:1), or a combination of degree and equivalent relevant experience to the same level, to join the M2A community of research engineers.
Please visit our website for more information on eligibility.
The scholarship covers the full cost of UK/EU tuition fees, plus a tax free stipend of £20,000 p.a. for a period of four years.