Complex sentence: The front frames are being cut at Corus Steel, Cradley Heath in the West Midlands, whilst detailed calculations are made to allow the rear portion to be cut, work is continuing on the smokebox with the frames expected to be erected during 2015.
Split into simpler sentences: The front frames are being cut at Corus Steel, Cradley Heath in the West Midlands. Whilst detailed calculations are made to allow the rear portion to be cut, work is continuing on the smokebox with the frames expected to be erected during 2015.