Derek Vanek, technical manager at SIFCO ASC, looks into how the marine industry can decrease costs and reduce downtime using selective plating methods as an alternative to disassembling components for repair.

Typical component problems and issues can include; fretting or wear on bearings fits and flanges due to continuous vibration, extensive wear on bearing cap faces and saddle areas, corrosion on various components such as compressed air valves and parts exposed to sea water, steam cuts on high pressure turbine castings, worn Babbitt coatings on bearing shells, as well as out of tolerance or mis-machined shafts, housings and bearings.

Traditional plating

You may ask yourself why is an alternative plating method needed if the traditional method of tank plating is safe and still creates proven results?

Every second of downtime counts, as costs can mount up very quickly. The use of this traditional method can hinder the process and increase downtime further due to:

– The need to disassemble components

– The time it takes to transport from shipyard to plating facility

– The re-installation ahead of re-entering service

Tank plating involves the use of large tanks of preparatory and plating solutions and often requires extensive masking. The procedure is not portable, meaning the overall process, by nature, is rigid and not suited to components which need plating particularly fast.

Making protection portable

Selective plating has already been written into shipbuilding specifications. It is a portable method of electroplating localized areas of metal surfaces for OEM components, permanent repairs and salvaging worn or mis-machined parts; providing a fast, efficient and targeted solution to corrosion, wear, galling, solderability and brazing. And only four elements are required; a power pack, plating tools, plating solutions and a trained operator.

Unlike tank plating, selective plating can be performed in situ – the part or component does not need to be removed and transported to an external site. It can be brought into the shipyard, aboard vessels, or anywhere it’s needed to enhance or repair components, by any team member – certified technicians and engineers can take on the role after training, while the portable equipment facilitates machine shops at the point of repair.

The process not only exceeds the fundamental requirements of shipbuilding manufacturing, and repair and maintenance processes, it also provides a full circle of benefits, including quality, durability, cost saving, portability and time saving.

The process uses significantly smaller volumes of plating solution than tank plating, using only the required material. There may be no need for disassembly or transportation, and minimal masking and post-machining; just a quick process that extends maintenance intervals and service life.

What’s more, through the ASTM C633-79 Standard Test Method for Adhesion or Cohesive Strength of Flame Sprayed Coatings, the SIFCO Process® also established that the cohesive strength of the deposit exceeds that of the bonding cement. For example, the minimum tensile strength value established (at the point of cement failure during testing) for Nickel High Speed is 22,803 kPa (11,200psi) on a SAE 4130 steel base material. Additional qualitative tests, as described in AMS-QQ-N-290 were also conducted in which the plated areas were subjected to high stresses and strains. These results also showed excellent adhesion.

For more information on using the SIFCO Process on-board your ship, call 800-765-4131 or email us as info@sifcoasc.com