This describes a repair
made to an RT-Flex engine, after two piston rod palm nuts came
loose and worked their way up the threads, until they started to
impact on the underside of the stuffing box. The stuffing box
was broken and replaced, but the diaphragm plate was cracked at
the bolt holes where the stuffing box is secured into the
This photo shows the crack on the pump side of the
engine: the crack is 280mm long.
This photo shows the crack on the exhaust side of the
engine: the crack is 70mm long.
The cracks were repaired
A stop hole was drilled at the end of the horizontal
crack on the pump side
The diaphragm plate was drilled across the crack and a
locking key fitted
The damaged bolt hole was drilled out and a plug
The horizontal crack was chain drilled and tapped.
And stitching pins screwed in.
The vertical crack was chain drilled.
The drilled holes in the vertical crack were then tapped
Stitching pins screwed in
Stitching pins cut off close to surface
Overlapping stitching pins
Grinding the stitching pins flush with surface
crack on the exhaust side was repaired in a similar