kaputnik wrote:

That depends completely on the ship. Here it's definitely the automation system. We had this wonderful old ABB Selma system (which btw was a really cool modular 8086 system (and yes, I kept the CPU and FPU when it was scrapped 😁)), but they stopped making spare parts, so we had to retrofit a modern system, that really sucks. On my last ship it was the licence built Wärtsilä 46 main engines, they had quite a lot of material problems.

What sends them to Alang is usually the 25 year classification. Before that, they are classed according to the rules that were in effect when the ship was built. At the 25 year classification, they have to comply to the same rules as a newly built ship. It's usually far too expensive to rebuild/retrofit a ship which doesn't have all that many years of lifetime left anyways according to that.

I understand that most vessels have extensive spares in storage. For everyday physical repairs, what's the rough breakdown between high level (LRU swap) and low level (fabricate new part / rig up bypass) repairs?

gdjacobs wrote:

I understand that most vessels have extensive spares in storage. For everyday physical repairs, what's the rough breakdown between high level (LRU swap) and low level (fabricate new part / rig up bypass) repairs?

That also depends on the ship, and what piece of machinery we're talking about. It's impossible to figure out some kind of ratios.

Here we do quite short voyages within Europe, so availability and delivery times isn't really a problem. We use premade spares when we have them in stock - which we have for most mission critical stuff - or they can be delivered within an acceptable timeframe. There's a lot of redundancy on this kind of ship too, the only thing during my years here that has held us up more than a few hours so far is that goddamn automation system. It should be mentioned that I've been blessed with an extremely skillful engine crew on this ship though.

We're also limited by our fabrication equipment, it's not like we can turn a new piston for the main engines or something like that. Most small stuff is no problem though.

The ship is built in Poland in the 90's; a lot of equipment is made by obscure Polish companies that might not even exist anymore, and for that stuff it's hard to get spares. My fitter is a freaking wizard in the workshop though, asked him several times where he's hidden the CNC machine when he delivers something I've asked him to make 😜 There's really nothing he can't make with just a lathe, a drill press, a belt grinder, a welding set, and some hand tools. Wonder what will happen when he retires next year... 😜

An earlier ship I worked at was a container liner going between Europe and the Americas. There we had a lot less redundancy, but way more extensive spare stores. Basically we had everything but engine frames and stuff like that we had no means to replace on our own. We did however have a spare Ø 7m propeller lying around on the lowest deck 😁

Edit: oh, and that's the last shipping related question answered here, feeling that I've derailed this thread completely already 😀

It feels almost off-topic now, but if there's room in the case and structure (like a drive cage) to attach to, and you're careful not to ground anything that shouldn't, then consider just putting massive heatsinks on everything that gets hot (the biggest socket-compatible unit for the CPU, specialized adhesive for the memory, northbridge etc).

THEN you get some armature wire (aluminum allow bendable wire for sculpting or craft), or rubber-coated plant stem wire of a decent diamater, and use it to mount one or more 120mm fans in the case pointed so they blow over the heatsinks directly and one to exhaust the case. You can put the wire through the fan mount holes and bend the ends back, they're strong enough to hold a fan up (especially 2 or 4 wires).

It'll look a little funky, but it'll move air and heat. The heavier the heatsink and the smaller the fins, roughly, the better. So thin metal aluminum fins are better than a copper block, but thin copper fins are better than thin aluminum fins.

I have a plan, sort of, to build a late 386 or 486 (or even fast 286) "modern gaming machine" in a compact modern window case with lighting and a custom large cooling fan, to basically look as confusing a mashup between old and new designs as possible.

Edit: I forgot that Masterbond and Arctic make heatsink adhesive, you can look them up online.