669 Demonstrate Knowledge of Grinding Wheels and Fluids

Explanatory notes

1The following apply to the performance of all outcomes of this unit standard:

aAll work practices must meet recognised codes of practice and documented worksite health and safety and environmental procedures (where these exceed code) for personal, product, and worksite health and safety, and must meet the obligations required under current legislation, including the Health and Safety in Employment Act 1992, the Resource Management Act 1991, and their subsequent amendments.

bAll work practices must meet documented worksite operating procedures. This includes the recording (by electronic or non-electronic means) of activities, events, and decisions.

cAll evidence of communications gathered in relation to this unit standard must be in accordance with worksite procedures for content, recipient, timing, and method.

2Definition

Worksite policies and procedures refer to documented policies and to documented or other directions provided to staff. These include, but are not limited to, ways of managing health and safety, environmental considerations, quality, and production, and must conform to legislation. Examples include standard operating procedures, company health and safety plans, on-site briefings, and supervisor’s instructions.

Outcomes and evidence requirements

Outcome 1

Demonstrate knowledge of grinding wheel and/or stone shape and structure.

Evidence requirements

1.1Characteristics of grinding wheels and/or stones used in the workplace are matched with their code letters and shapes.

1.2Manufacturer’s specifications are interpreted for all wheel types used in the workplace.

Rangeabrasive type, grit size, wheel grade, abrasive structure, bond type.

1.3Types of abrasives are explained and matched with their applications.

Rangeabrasives – aluminium oxide, silicon carbide, cubic boron nitrate, diamond.

Outcome 2

Perform grinding wheel calculations.

Evidence requirements

2.1Revolutions per minute (RPM) of a grinding wheel spindle are calculated, given motor RPM, drive pulley diameter and driven pulley diameter.

2.2Rim speed of a grinding wheel is calculated, given spindle RPM and wheel diameter.

2.3Wheel speeds are calculated to enable safe operation, and to prevent burning of material, undue wheel wear, glazing, and clogging.

Outcome 3

Explain the selection of grinding wheels for different applications.

Evidence requirements

3.1Selection to match wheel dimensions with grinder capacity is explained.

Rangediameter, thickness, bore size, shape, speed.

3.2Selection to match wheel specifications with the task to be performed is explained.

Rangespecifications – grit and grade ratings;

tasks – wet or dry grinding, stock removal requirements (rough or finish grinding), item being ground (saw sharpen, gullet), knife (sharpen), steel being ground (steel, tungsten carbide), sharpening, shaping, finishing.

Outcome 4

Explain grinding wheel inspection and storage techniques.

Evidence requirements

4.1The inspection of grinding wheels is explained in accordance with worksite policies and procedures.

4.2The requirements for storing wheels according to worksite policies and procedures for avoiding moisture absorption and breakages is explained.

4.3The need for stock rotation according to worksite policies and procedures is explained.

Outcome 5

Explain grinding fluids and their use.

Evidence requirements

5.1Reasons for the use of grinding fluids are described.

Rangeheat reduction, product quality, dust reduction, wear, and noise reduction.

5.2Types of grinding fluids are identified.

Rangefluids – water with anti-rust, water and oil emulsion, pure oil.

5.3Method for maintaining coolant/water ratios during grinding is described.

5.4Fluid components are explained in accordance with manufacturer's specifications.

5.5First aid data are interpreted from relevant grinding fluid Safety Data Sheets (SDS).

Rangeswallow, inhale, splash in eye or skin.

5.6Grinding fluid storage and chemical handling requirements are identified from the relevant grinding fluid Safety Data Sheets (SDS).

Status information and last date for assessment for superseded versions

This CMR can be accessed at

Please note

Providers must be granted consent to assess against standards (accredited) by NZQA, before they can report credits from assessment against unit standards or deliver courses of study leading to that assessment.

Industry Training Organisations must be granted consent to assess against standards by NZQA before they can register credits from assessment against unit standards.

Providers and Industry Training Organisations, which have been granted consent and which are assessing against unit standards must engage with the moderation system that applies to those standards.

Requirements for consent to assess and an outline of the moderation system that applies to this standard are outlined in the Consent and Moderation Requirements (CMR). The CMR also includes useful information about special requirements for organisations wishing to develop education and training programmes, such as minimum qualifications for tutors and assessors, and special resource requirements.

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