Marine Protection

SUBMARINES

To date we have undertaken many projects for the Australian based Submarine Corporation for work on the Collins Class Submarines. All work was carried out under strict test conditions.

Prior to commencing the plating project a test piece of the same base material was completed so that tests of a destructive nature that would not have been possible to carry out on the actual work piece could be completed. The test piece was then sent to a laboratory for such tests as thickness, adhesion, micro cracking, durability, and salt spray. After successful completion of these tests we were allowed to commence plating. During the plating operations the process was frequently suspended so that on site testing for adhesion, thickness and micro cracking (non destructive) could be carried out. Again after successful completions of these tests we were allowed to re-commence.  

Conditions of high cleanliness had to be maintained at all times, plus observation of all navel rules and regulations, often the work had to be undertaken while the boat was still in the water, in which case many safeguards were necessary as the work entailed the opening or dismantling of external hull valves.

All work personnel under took a comprehensive work practice and safety procedures course lasting 3 days, during the time of our work further courses in confined space and hazardous environments were completed.

As many of these projects were of an emergency nature, work often had to be done on a 24 hour bases using 2 shifts on a 12 hour rotation

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PROJECTS COMPLETED: 

 

1. Filling pock marks and sever pitting (some holes to a depth of 3mm) caused by a combination of electrolysis and corrosion due to the many different metals and exposure to salt water. The main fill metal used was an alloy of Nickel and Cobalt again this solution material had to be approved for use on the submarines.
 
2. Replacement of corrosion coatings using a combination of Nickel HB to 200 microns with a further 200 microns of Nickel Tungsten alloy as a final coating. This was carried out on very complex shaped surfaces often in excess of 300 square inches, utilising custom designed anodes and flow through technology for solution delivery to the plating surface.
 
3. Heavy build-ups on selected areas to 1000 microns using a combination of Nickel HB, Nickel Cobalt alloy, and Nickel Tungsten alloy. These surfaces were often in excess of 50 square inches, and of an undulating and irregular nature.
 
4. Resizing, repairing and corrosion coating extremely large screw threads on the hatch sealing mechanism using a combination of Nickel HB and Nickel Tungsten alloy.
 
5. Spot corrosion coatings to various internal and external machine parts mainly using Nickel and Nickel Cobalt alloys.
 
6. Stripping existing pitted corrosion coatings off base material using a reverse electro chemical etching process.