Steel and Surface Preparation
What is meant by the tenn sliver? What is a hackle? Name two other tenns that could be used for ‘anchor pattern’? What are the main advantages of using ‘Testex papers’ for measuring profiles? What is meant by the tenn grade. relating to a blast finish? What are the main factors governing the grade f a blast finish? Can the grade of a blast fmish be detennined by using the surface comparators to BS 7079 Pt C3? What profile range can be measured using X coarse Testex? What profile range can be measured using coarse grade Testex? What are the two theories of adhesion?
Briefly describe the mechanisms of the two theories of adhesion. How many microns are in Ithou? Give three different names for the cross section of a blast. What is the approximate speed of abrasives leaving a venturi nozzle? What is the most common cause of flash rusting on a blasted substrate? What would be considered to be an ideal shot grit mix? What is the purpose of mixing shot and grit? Which abrasive would have the effect of work hardening a substrate? Name three methods of measuring or assessing a profile. What is the most common cause of rogue peaks on a substrate?
In what situation would it be better to use steel grit in preference to copper slag abrasives? If cracks or laminations are found on a substrate after blasting what steps should be taken? Using comparators to ISO 8503, what are the three main profile assessments? What are the other two assessments when the above three are not appropriate? What would be size of copper slag needed to give a protile of 50 to 75 urn? 3. 2 copynght