Metalock's Global Steel Reputation
Due to the severe operating conditions in steel plants, regular refurbishment of heavy rolling mills is
essential to ensure efficient production and consistent product quality. Window areas on roughing and
subsequent finishing mill stands suffer erosion and corrosion due to the very nature of the steel rolling
process and once resultant wear reaches a certain point, it becomes necessary to remove old wear plates,
remachine the surface behind them to restore original manufacturing tolerances for squareness, straightness
and dimensional accuracy. New oversize wear plates are then fitted.
The shear size of the mill housings means that the remachining needs to be carried out in-situ. For this
reason Metalock Engineering UK has built up an extensive range of precision on site machining equipment
specially designed in-house for steel mill refurbishment. These machines, together with the company’s team
of highly skilled engineers and technicians, all of whom have many years of experience with steel projects
both large and small all over the world, are enabling Metalock Engineering to establish a global reputation as
the market leader in this type of machining work.
Drilling & tapping
As well machining the wear areas, before new wear plates can be fitted, many of the tapped holes for the
plate bolts often need to be refurbished. The constant pounding of rollers on hot steel and the vibration
cause the threads to gradually deteriorate. In addition to the milling machines for surface work Metalock has
developed a range of drilling equipment to redrill and tap all the holes.
Not only is the Metalock mill housing equipment suitable for machining vertical surfaces it is also used to
remachine the housing bases flat and level with each other and square to the housings themselves.
Increasingly, Metalock is carrying out reboring for upgrades of mill screwdown systems and like the drilling
procedures this work is performed using an adaptation to the mill housing remachining system. This means
that the range of Metalock equipment available for steel plant work encompasses milling, drilling and
tapping, boring and facing.
Orbital turning
One of the latest pieces of equipment to be developed is an orbital turning machine which was designed for
machining and reprofiling 0.5 metre diameter X 1.5 metre long stub shafts for a beam straightening/finishing
machine at Corus, Teesside. To speed the orbital turning operation and ensure that all seven shafts
matched, Metalock fixed a template of the stepped profile to the orbital turning device. The tools followed
this profile, as in a copying lathe.
Global operation
Metalock Engineering’s reputation is growing apace and as well as roughing mill stand refurbishments at
Corus, Llanwern; the reversing roughing mill at Corus, Port Talbot and the orbital turning project on the
seven beam straightening machine shafts at Corus, Teesside, the company has carried out projects in Spain,
at Aviles for Aceralia refurbishing eight screwdown bores; refurbished four mill stands for Sollac in Marseilles
and done similar work for Iran Steel in Esfahan. Such is the company’s experience in this type of work that
all the contracts were accomplished within the time and budgets allocated by the client to the satisfaction of
all concerned.
In past years Metalock has carried out works in steel plants in Poland, Turkey, Chile, Norway, Sweden,
Belgium, South Africa, India, Romania, China, Canada and the USA.
Cast iron repairs
In addition to the machining work Metalock Engineering UK is the largest and most successful company in
the world specialising in cold repairs to cast iron using the Metalock process. This technique was developed
over 70 years ago for the repair of castings in iron, bronze, aluminium and steel that have been cracked or
broken. Because it is a cold repair it avoids the normal stress problems associated with welding.
The Metalock process is the accepted repair technique for all cracked, broken and damaged castings in a
wide range of industries, for a multitude of applications. The repair consists of peening layers of Metalock
special nickel alloy multi-dumbbell shaped keys into prepared apertures. These keys are highly ductile and
can be peened into a metal-to-metal condition to become almost integral with the component’s parent metal.
Metalock keys are manufactured in a variety of sizes to suit each individual job. Their high strength ensures the return of a high percentage of the original strength. The essential advantages of the Metalock repair are
that no heat stresses are introduced, no distortion occurs and in many instances machining is unnecessary.
The process is invaluable in emergency situations and in many cases where the component is accessible,
it can be done in-situ to avoid costly dismantling and re-assembly.
When it comes to providing specialist services to the world steel industry, Metalock is one of the leaders by
offering its skills in In-Situ Machining, Cold Repairs to Cast Iron and Cast Iron Fusion Welding, For those
who require it, the company provides alignment services and has a comprehensive in house machining
facility at its headquarters in Coventry, England.