Crack Arrester Holes

[Merlyn]

Let's be honest, how many have you done in your career to date?

[JollyJack]

cracks at the corners of bulker's hatches, drilled the ends, ground a vee along the crack and welded it. deck cracks at the base doublers of deck cranes, same thing. Cylinder head cracks, drilled either end, grind a vee and stitchlok the crack. Hard chine hull, crack along the join of vertical side strake and bottom plate, ends drilled and 15 gallons of Araldite poured into a wooden form., It worked, too! I have no doubt the ship was scrapped many years later with Araldite still holding the hull together!

[Merlyn]

Well JJ and I thought you were a devoted Belzona fan. Shame on you, all that Araldite when Mr Belzona was there for you. Trying to remember a stitch repair done on an old Recip engine when I first started out. I was not directly involved with it but working in the same engine room. Seemed to remember loads of holes drilled and tapped either side of the crack ( no waterways here ) Taper bolts were used and heat, I think the idea was to attempt to reduce the crack width and stitching was involved somehow. Big old crack but the ship sailed on til it was scrapped 5 years later so must have been a success. Seen and done lots of heads but cracks near a valve seat insert ugh . Bad news or what.

[JK]

Long time ago we had a pump cover crack. The cover was at least a foot in diameter and an inch or more thick. We drilled it, put it in the galley oven for an hour and brazed it (brass). I'm thinking we put it back in the oven afterwards to cool it. I wonder if the cooks would let you do that now!
Also a fire main. It teed across the foscle of a bulker, a foot one side and 3-4 feet across the other side of the mainline. As the ship flexed, the pipe would crack. I drilled and welded it, next trip back I saw it was wrapped again. The design was bad, it had been fixed several times.
a coworker was telling me of a shallow crack in a oversized rudder stock. They did up a weld procedure, ground out the crack, drilled and welded. The stock is back in service.
Here in Canada with the Canadian Welding Board, CWB, there are thousands of weld procedures on file. Certified weld engineers develop weld procedures for theses special jobs and submit them to CWB for approval. These approvals are recognized by Transport Canada as a valid engineered repair. We have welded on seabay covers in water temperatures above 10*c with approved procedures.

[JK]

I remember another one, a crack in the cargo hold well of an OBO. CE asked me, I wouldn't do it. He said, the cargo hold is gas free, I said is it underneath? I was told (before?later?) on that same ship they had had the same type of crack. Drilled, ground the crack out and struck an arc...poof. Turned out when they put in the well, the original well was too deep, so they installed anther base above it. The crack had leaked and there was fuel below. I honestly can't remember if I knew before the conversation. The CE never pushed it so maybe he knew about it...which would be rather shitty.

[Merlyn]

That sounds like a Doctor Death job to me. You use mini flux A over there still?