Somers Forge - 3000t press crosshead casting repair
Casting repairs to a cracked forging press crosshead that Metalock Engineering carried out for Somers Forge
were originally designed to be of a temporary nature while the company waited for a new crosshead to be
delivered. In the event, the repair was so effective that the new component was never used.
Metalock Engineering was asked to give its opinion on the 200mm crack on the crosshead underside of one of
the company’s 3000t forging presses at Haywood Forge and was able to offer a metalock cold process repair
but with no warranties, due to the crosshead being of cast steel construction.
Somers had already decided to progress with a weld repair and had consulted the Welding Institute for the
correct procedure. A prominent welding company was called in and followed all the relevant procedures.
However, during the cooling process following completion of the weld, two new cracks appeared on the side of
the crosshead from top to bottom.
Metalock Engineering was asked to assist with the new problem and devised a metalock repair followed by
regular inspections thereafter. Following an NDT inspection the crosshead was marked out for milling to accept
“masterlocks” to restore strength to the crosshead. Seven rectangular masterlocks were used, three of which
were double masterlocks to provide increased strength. These were located at strategic points across the
fractured component. To save time, Metalock Onsite Machining department engineers used a portable milling
machine for the masterlock apertures and once machined the special steel masterlocks were inserted and
secured in place with dowels and studs. Finally the surface was peened and dressed.
To enhance the repair it was agreed at the design stage to fit specially made tie rods. Anchors for these
extended the full depth of the crosshead and the nuts for the tie rods were secured by locking pins to prevent
movement during forging production.
As a new crosshead had been ordered, Metalock inspected the repaired component on a weekly basis until it
arrived. However, this was never used, such was the effectiveness of the Metalock repair. Eventually, the
forging press was sold to an overseas company with the repaired crosshead intact and the new as a spare.
Met Rel 42
The Metalock repair was enhanced by fitting
tie rods. The repair was so good that the
new crosshead was never used