As we celebrate our 21st year of accelerated weathering and environmental testing for a broad range clients we strive to remain the most cost effective UKAS accredited materials testing laboratory in Europe offering a full suite of protocols for UV weathering, Taber abrasion, number plate, corrosion and environmental testing and I would like to thank all of our clients, both new and old for their continued support. Director Paul Edwards.
To make a valid assessment for GC for bolts, nuts, washers and screws against the sounding material, they should be tightened to the correct torque for the application. GC requires hard interference contact between the bolt/screw threads (inc boltheads and washers) and the surrounding hole threads. Loose bolts will allow moisture into the threaded holes that would otherwise be sealed when torqued down. When exposed / un-sealed hole threads are subjected to corrosion testing the corrosion failure mechanism is usually associated with low paint coverage down in the threads, not GC if the bolts are loose. Potential for GC is best measured by ensuring firm electrical contact (torqued down) in the presence of moisture to act as an electrolyte. GC will show local blistering and/or rusting around the bolt/nut arrangement and can sometimes show ‘jelly-like’ corrosion deposits rather like those seen in a dry-battery cell that has burst and leaked. 
AWL Ltd are pleased to be helping various UK companies with paint plants moving toward emission compliant all-electric curing ovens to replace outdated gas fired ovens. When a major change in a painting or coating process occurs (such as modified oven curing), previously validated paint systems must be re-validated for corrosion protection and other properties such as adhesion, hardness and wear resistance. Some of the UKAS accredited test methods available at AWL required for re-validation of paint systems include ISO 9227, ASTM B117, ASTM G85, ISO 12944 for corrosion performance and ISO 7784-2 or ASTM D4060 rotary Taber abrasion testing.
