single
Well-Known Member
I still don't get the seeing bit but I'll add a couple more. So what is the hull one doing if it can't see the engine.
Replacing a Hull Anode
- Thread starter WayneS
- Start date
Tranona
Well-Known Member
It is nothing really to do with the engine. The wire from the anode to the engine or gearbox is the path to the propshaft and prop. If you have a flexible coupling you need to bridge this to keep the continuity. The hull anode is bolted to the hull close to the prop.
single
Well-Known Member
Yeah,the wire goes to brushes on the shaft and to the engine block.
single
Well-Known Member
How do huge steel ships cope? i have never noticed massive anodes on them?
vyv_cox
Well-Known Member
They do have aluminium anodes but they also use impressed current with a supplied voltage to reverse corrosion effects. Simple diagram here http://www.bing.com/images/search?q...70D8688FFC8013DAD1248847273F&selectedIndex=21
Robg71
Well-Known Member
Anode blocks on the ship i work on are about 50kg each. Ship is 22,000 tonnes, so still a tiddler. We have no impressed current.
The oil rigs, and sub sea installations and wells, are also linked with anode skids. Some also use impressed current. The cathode is generally a dirty great platinum ring....
Depending where, but we generally re-new them with a complete skid assembly, with a 10mm stainless cable daisy chaining them all together. pipelines have anode bracelets around the field joints that are not protected in concrete... The rig anodes are replaced by bolting new ones in a clamp on arrangement. Otherwise it means struggling to get in a welding habitat in situ to replace, and that gets expensive...
The oil rigs, and sub sea installations and wells, are also linked with anode skids. Some also use impressed current. The cathode is generally a dirty great platinum ring....
Depending where, but we generally re-new them with a complete skid assembly, with a 10mm stainless cable daisy chaining them all together. pipelines have anode bracelets around the field joints that are not protected in concrete... The rig anodes are replaced by bolting new ones in a clamp on arrangement. Otherwise it means struggling to get in a welding habitat in situ to replace, and that gets expensive...
VicS
Well-Known Member
The cathode is generally a dirty great platinum ring....
Anode you mean ! At around £30 per gram a "dirty great platinum ring" costs bob or two then ?
Robg71
Well-Known Member
At around £30 per gram would you want to see your platinum dissolve....
Its not sacrificial....
The "scrap" we removed from brent flare stack dissapeared very quickly.... Suprisingly enough
Try an 8ft diameter ring about two inch thick...
Its not sacrificial....
The "scrap" we removed from brent flare stack dissapeared very quickly.... Suprisingly enough
Try an 8ft diameter ring about two inch thick...
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oldsaltoz
Well-Known Member
Just wondering if that wire is there because the rudder stock is isolated by the bearing material being non conductive?
Good luck and fair winds.
Good luck and fair winds.
single
Well-Known Member
Just wondering if that wire is there because the rudder stock is isolated by the bearing material being non conductive?
Good luck and fair winds.
Yes, the rudder will be isolated because of the nylon lower bush.I'll put the wire back on.Its no hassle and can't do any harm.
