QUESTIONING THE OBVIOUS: THE WAY TO PERFECT PRODUCT FINISHING

Malcolm Griffiths & Graham Armstrong

Many Surface Coatings Problems Occur Because:

The Correct Specification Is Never Established

No Testing Regime Has Been Put In Place

Why the Obvious?

Involve:The End SpecifierThe Product ManufacturerThe Coatings ApplicatorThe Coatings Manufacturer

A Multi Way Event

The Use of The Coated ComponentThe Environment It Is To Be Used InA Sensible Testing Regime For: Type Testing

Batch TestingThe Ability For All Parties To Keep To RequirementsDocumentation/Record Keeping

What To Consider?

1.) Vehicle Cabs2.) Over-coating Pre-Coated Steel3.) Architectural Acoustic Panels4.) Aluminium Windows5.) Playground Equipment

Some Examples Of It Going Wrong!

TGIC Polyester Powder Coated Steel CabGlazed Windows Set Into A Silicone Sealant

No Compatibility Testing between Powder & Sealant (Type or Production)

Vehicle Cabs

Change In Quality Of Powder to A TGIC Free Version (Environmental & Safety Issues)New Grade Powder Contained Surface AdditivesChange Effected with No Thought To Testing

Result: No Adhesion Of Sealant To Powder Windows All Fell Out!!!

Vehicle Cabs

Polyester Powder Applied Over Pre-Coated Steel

Trade Coater Application

No Built In Controls On Oven

Oven Varying In Temperature

Over-Coating Pre-Coated Steel

Result: Varying Adhesion Of Powder Coating To Pre-Coated SubstrateSome Random Total Adhesion Loss

Simple Regular Oven Testing (Data Logger) Would Have Eliminated Problems

Over-Coating Pre-Coated Steel

Steel Wall Panels For Use in Prestigious University FoyerDesign Featured Multi Hole Acoustic Effect

Polyester Powder Coating The Chosen FinishColour Selected From RAL Range

Multiple Batches of Powder Coating

Application Through One (Respected) Powder Trade Coater

Architectural Acoustic Panels

Lack Of Correct Control Of Colour:At Powder ManufacturerAt ApplicatorAt Site Inspection

Included A Lack Of Knowledge Of Colour Judgement Both Instrumentally & Visually

Architectural Acoustic Panels

Result:“Patchwork Quilt” Effect on Built Wall

Architectural Acoustic Panels

Architectural Acoustic Panels

Acrylic Finish Black For Aluminium Mullion Window Sections

Coating Applied At Trade Coater, But Pre-Treatment Applied At Another Coater

No Durability Testing Over “Aged” Chromate Pre-Treatment (Including Variations In Dwell Time)

Aluminium Windows

Result: Rapid Corrosion Of Aluminium Extrusions Under Acrylic Coating; Visible As White Spotting On

Black Surface

All Windows Required Stripping and Re-Coating: £250K COST

Aluminium Windows

Manufacturers Of Heavy Duty Playground equipment (Council Use)

Heavy Section Tubular Steel Construction

Original Specification: Zinc Rich Powder Primer

Polyester Powder Finish

Playground Equipment

Cost Saving Generated Change To Primer:

From: Zinc Rich (Proven Corrosion Performance)

To: “Standard” Powder Primer

No Performance Testing Completed Before Change Effected

Playground Equipment

Result: Severe Corrosion Problems In Service

Severely Reduced Life Cycle Of Equipment

Zn Rich

Std

Playground Equipment

WHERE TESTING IS THE NORM

Aerospace Industry

Pre-Treatments & Coatings

Coated Components

Documentation/Traceability

Result: Minimal Component & Coating Failure

Type & Batch Testing

Involve All PartiesAgree Specifications and Testing Regimes(Prototype Phase & Production Phase)Document Process & Test ResultsQuestion The Obvious

Result: PERFECT PRODUCT FINISHING

Conclusions

For More Information

Please contact Indestructible Paint 0121 702 2485