The Spartan UK plate mill is a quarto universal reversing mill, with automatic gauge control, capable of producing up to 200,000 tonnes per year.
Before the finished steel plate is shipped to the customer, it goes through the following manufacturing process.
Quarto plate is rolled from slab supplied by fully integrated steel mills. Spartan UK holds approximately 2-3 months of slab in stock, covering all the grades and sizes in the product range.
The majority of the slab is supplied by Metinvest along with some from West European producers. It is shipped in to the Port of Sunderland by bulk carrier and stored in the docks, 12km from the mill.
Each individual slab is moved from the port to the plant when it is required to meet a customer’s order. The slab is flame cut on site to the exact dimensions required for the plate to be produced.
The cut slab is reheated in one of five natural gas fired furnaces. According to slab size one of four batch furnaces, installed in the last 4 years, or a high capacity multizone pusher furnace is utilised.
Once heated to the required temperature, the slabs are descaled top and bottom, using high pressure water jets to remove scale from the surface, which is a natural by product of the heating process.
Quarto Reversing Rolling Mill
The slabs can range in thickness from 300mm to 190mm. To reduce the thickness and to match the customer’s dimensional requirements, the slabs are rolled through the quarto reversing mill. The number of passes through the mill depends on the initial thickness of the slabs and on the dimension of the plate required. This process is controlled precisely by an adapted automation system. Accurate thickness tolerances are guaranteed through a sophisticated on line laser gauging machine.
The Quarto Mill is driven by Converteam, a pair of 2.5MW induction motors installed in 2008. These state of the art motors and control systems have facilitated much improved productivity, output, quality and reliability for the mill.
Head & tails of the plate up to 30mm thick are cut by the hot shear. Thickness is excess of 30mm are cut at a later stage by the on line oxy-acetylene cutter.
The plate then passes through the levelling machine while still hot, to ensure the plate meets the flatness standard required.
The plates are then held on the cooling bed to cool and are inspected for surface quality and dimensional accuracy.
Additional levelling can be undertaken once the plate has cooled using the cold levellers.
Punching & Marking
The plates are punch marked with numbers to give full traceability of the plate. Bar code and grade/dimensions labels are fixed to the plate.
Plates from Spartan UK are predominantly supplied with mill edges as rolled. On request the edges can be cut off line by an oxy-acetylene cutter to give a flat edge.
Plates up to 8m long can be heat treated using the one of two normalizing batch furnaces.
Approved contractors can heat treat plates longer than 8m as well as shot blast and prime plates when required by customers.