Corrosion Protection

Summary report of project for

C5M Corrosion Protection

in compliance to ISO12944 & ISO20340 for

Ductile Iron Heavy Section Castings

A T Ansari

September – October 2010

Background

• Issue:– Customer complaints for corrosion

• Existing concerns– Supplier awareness

– Specification clarity

– Reference to international standards

Specification given to supplier

– Sand blasting according to ISO 12944-4 SA 2 1/2

– First Coat

– Intermediate coat

– Top coat

– Shade

– Nominal DFT

Concerns

– Issues observed once components reached to assembly plant or to customer

– Paint peel off

– Mud cracking

– Film thickness variation

– Poor SST life

– Catching early corrosion

Actions steps

– Plan

• Review and improve specification

– Do

• Assessment of supplier facilities

• Gap analysis

• Action plan

– Check

• Facilities verification

• Coating as per revised specification in improved facility

• Inspection

– Act

• Feedback from assembly plant

• Feedback from customer

Do

CheckAct

Plan

Specification Improvement

• Clarity in specification– Surface cleaning and preparation

• Instead of earlier sand blasting specified grit blasting

• Defined acceptance criteria for cleanliness

• Defined acceptance criteria for surface roughness after blasting

– Coating application• Recommended paint chemicals

– Inspection & testing• WFT inspection

• Paint DFT inspection as per ISO19840

• Pull off test

– Validation• Cyclic aging test as per ISO20340

Supplier assessment & actions

• Assessment gaps in areas of– Machinery and equipment

– Measurement & testing facilities

– Skilled work force

– Subject matter expertise

• Actions– Worked with suppliers to upgrade their facilities

– Arranged training sessions with Supplier’s team

– Worked with Suppliers HR team to identify training gaps and training calendar

Trial Run, inspection, testing & validation

• Production trial run - OK

• Individual layers WFT – OK

• Dry Film Thickness – OK

• Pull off Test – OK

• Sample submitted for aging test – Test OK

Steps taken during the project are explained in shortest possible way.

Contact abdullahta@gmail.com to understand in detail with specific question in case of any query.

Thank You