Please note that this is to let you know of an issue that has recently come to light. We don’t know the size of the installed population of this type of boiler so cannot judge this in any statistical sense.
NB. One of our members who run Maxecon Boilers has failed its NDT SBG01 examination.
Defects were found between the end plate and the furnace tubes, and on subsequent inspection a crack at the toe of the weld was found on the fillet weld of the end plate to shell. The crack starts at the 4 O’clock position and finishes at the 8 O’clock positions. In some places it is 10mm deep (the parent metal thickness is 20mm) and is a finger nail thickness crack.
According to an Insurance inspector, this is the 3rd Maxecon Boiler in three years that has failed the NDT in exactly the same way. All of these boilers were built in the early 70’s so have been in service for a significant length of time, often used as auxiliary boilers.
It was commented that it is good that this has been found now (2015), as it was not found at the last inspection in 2010. Their other Maxecon Boiler failed in 2010 with defects in the furnace tube.
We would just like to make other owners of Maxecon Boilers aware of this possible problem and to specifically look for this at the next NDT inspection.
It is alway difficult to be sure where the crack originates from and how long it has been there, but the usual NDT on the shell to end plate would be 6 O’clock, 12 O’clock and 2 other position to a total of 20% of the total circumference.
The Furnace mouth is 100% checked every 5 years so the defect in this location had occurred after the previous NDT and within the last five years, this could be as a result of a more cyclic loading than previous boiler operations.
16-07-2015 End
