Elements and Performance Criteria

Context
This unit of competency includes various types of wet milling equipment (select the types relevant to your plant):
vertical
horizontal
bead mills
roll/ball-type mills.

This unit also covers ancillary equipment which form part of the wet milling system. For your plant this may include (select relevant items):
pre-mix vessels
coolers, cooling jackets and heat exchangers
pumps
vessels, tanks
piping systems
valves and flanges
sumps and drains.

Typical problems for your plant may include:
condition and life of beads (if applicable)
condition of rollers/balls (if applicable)
cooling system fouling
blocked filters or piping
high/low levels
loss of process cooling resulting in high process temperatures
equipment failure or shutdown resulting in loss of feed to process
excess/unexpected sand production
composition changes.

All operations are performed in accordance with procedures and relevant legislative or site specific safety requirements.

HSE
All operations to which this unit applies are subject to stringent health, safety and environment requirements, which may be imposed through State or Federal legislation, and these must not be compromised at any time. Where there is an apparent conflict between performance criteria and HSE requirements, the HSE requirements take precedence.

Assessment context and methods
Assessment for this unit of competency will be on an operating plant. The unit will be assessed in as holistic a manner as is practical and may be integrated with the assessment of other relevant units of competency. Assessment will occur over a range of situations that will include disruptions to normal, smooth operation.

Simulation may be required to allow for timely assessment of parts of this unit of competency (e.g. element 6). Simulation should be based on the actual plant and will include walk throughs of the relevant competency components. Simulations may also include the use of case studies/scenarios and role plays.

This unit of competency requires a significant body of knowledge which will be assessed through questioning and the use of what if scenarios both on the plant (during demonstration of normal operations and walk throughs of abnormal operations) and off the plant.

Critical aspects
Competence must be demonstrated in the ability to recognise and analyse potential situations requiring action and then in implementing appropriate corrective action. The emphasis should be on the ability to stay out of trouble rather than on recovery from a disaster.

Consistent performance should be demonstrated. In particular look to see that:
early warning signs of equipment/processes needing attention or with potential problems are recognised
the range of possible causes can be identified and analysed and the most likely cause determined
appropriate action is taken to ensure a timely return to full performance
obvious problems in related plant areas are recognised and an appropriate contribution made to their solution
pre-start checks are made to ensure equipment is lined up to the plant in accordance with procedures and/or manufacturers specifications.

These aspects may be best assessed using a range of scenarios/case studies/what ifs as the stimulus with a walk through forming part of the response. These assessment activities should include a range of problems, including new, unusual and improbable situations that may have been generated from the past incident history of the plant, incidents on similar plants around the world, hazard analysis activities and similar sources.

Resource implications
Assessment will require access to an operating plant over an extended period of time, or a suitable method of gathering evidence of operating ability over a range of situations. A bank of scenarios/case studies/what ifs will be required as will a bank of questions that will be used to probe the reasoning behind the observable actions.

Other assessment advice
In all plants it may be appropriate to assess this unit concurrently with relevant teamwork and communication units.

Essential knowledge
Competence includes an understanding of demonstration of competence in this unit must include knowledge of:
all items on a schematic of the mill system and describe the function of each
principles of milling equipment operation
physics relating to the particular process
process equipment operating parameters
process and product variables
bead life (if beads are used in process).

Competence also includes the ability to distinguish between causes of problems/alarms/fault indications such as:
equipment malfunction (including consequences and potential for escalation)
plant not performing to design
bead life, roller/ball wear or adjustment (as applicable).