Abrasive Wheels Training Certificate Abrasive Wheel Types & Grades

Question 1

Which BS EN standard specifies the safety requirements for abrasive wheels used with angle grinders?

Accepted Answer

BS EN 13743 and BS EN ISO 603

Answer

BS EN 50144

Answer

BS 8888

Answer

BS EN 60745

Question 2

What does the 'grade' of an abrasive wheel refer to?

Accepted Answer

The hardness of the bond holding the abrasive grains together

Answer

The grit size of the abrasive particles

Answer

The maximum operating speed in RPM

Answer

The diameter of the wheel in millimetres

Question 3

What is the purpose of the 'structure' designation of an abrasive wheel?

Accepted Answer

To indicate the spacing (porosity) between abrasive grains — open structure for soft materials, dense structure for hard materials

Answer

To describe the wheel's thickness

Answer

To specify the operating temperature range

Answer

To indicate the bonding material used

Question 4

Which bonding material is most commonly used in abrasive wheels for general grinding?

Accepted Answer

Vitrified bond (ceramic)

Answer

Resinoid bond (synthetic resin)

Answer

Rubber bond

Answer

Shellac bond

Question 5

What is the purpose of the abrasive grain type designation on a wheel specification?

Accepted Answer

To identify the abrasive material (e.g., aluminium oxide for steel, silicon carbide for non-ferrous) for matching to the workpiece

Answer

To indicate the depth of cut achievable

Answer

To specify the maximum workpiece hardness

Answer

To describe the wheel's colour coding for RPM rating

Question 6

What does 'grit size' (also called grain size) specify on an abrasive wheel?

Accepted Answer

The coarseness or fineness of the abrasive particles — lower numbers indicate coarser abrasive, higher numbers indicate finer abrasive

Answer

The number of abrasive particles per square centimetre

Answer

The particle size in microns only

Answer

The maximum depth of cut per revolution