Elements and Performance Criteria

RANGE STATEMENT
The Range Statement relates to the unit of competency as a whole. It allows for different work environments and situations that may affect performance. Add any essential operating conditions that may be present with training and assessment depending on the work situation, needs of the candidate, accessibility of the item, and local industry and regional contexts.
Where reference is made to industry codes of practice, and/or Australian/international standards, the latest version must be used.
Context
This competency applies to all work environments and sectors within the plastics, rubber and cablemaking sectors. It includes the operation of all relevant ancillary equipment where that equipment is integral to the extrusion process.
Procedures
All operations are performed in accordance with procedures.
Procedures include all relevant workplace procedures, work instructions, temporary instructions and relevant industry and government codes and standards.
Products
These may include:
rod
sheet
film
profile
tread profile
cable.
Competence under this competency unit is only required in one process.
Materials
This unit applies to most plastic and rubber materials, including compounded PVC fed to the extruder as pellets. It does not apply to dry blended PVC powder (refer to PMBPROD334A).
Tools and equipment
This competency includes use of equipment and tools such as:
extruder equipment and components such as main drive, gearbox, thrust assembly, adapter, gate, breaker plate, screen pack, doser, screw/s, barrel, heaters, thermocouples
extruders, either single or twin screw
extrusion dies - rod, sheet, film, pipe, profile, tread profile and cable auxiliary equipment - water pump, feeders, hopper loader, pelletiser, dehumidifiers, etc
tools for taking samples
relevant personal protective equipment.
Hazards
Typical hazards include:
vapours
burns
moving equipment
hazardous materials
manual handling hazards.
Problems
Respond to 'routine problems' means 'apply known solutions to a variety of predictable problems'. Typical process and product problems may include:
equipment malfunction
variations in materials
contamination of materials or additives
temperature/speed variations
routine product extrusion faults - dimensions, surface appearance, colour, deformations
incorrect quantity of materials.
Variables
Key variables to be monitored include:
differences between actual and set temperatures
speeds, including screw speed and haul-off
colour and uniformity
surface finish and appearance
product finished thickness
output rate
product integrity and general conformance to specification/sample.

The Evidence Guide provides advice on assessment and must be read in conjunction with the Performance Criteria, required skills and knowledge, the Range Statement and the Assessment Guidelines for this Training Package.
Overview of assessment
A holistic approach should be taken to the assessment.
Assessors must be satisfied that the person can consistently perform the unit as a whole, as defined by the Elements, Performance Criteria and skills and knowledge.
Critical aspects for assessment and evidence required to demonstrate competency in this unit
It is essential that competence is demonstrated in the knowledge and skills defined in this unit. These may include the ability to:
recognise the importance of material properties and qualities
apply approved procedures
take appropriate action to resolve faults or report faults to appropriate personnel
explain and implement emergency shutdown procedures.
Consistent performance should be demonstrated. For example, look to see that:
extrusion production standards are met consistently
upstream and downstream communication is timely and effective operating procedures and work instructions are read and interpreted correctly
problems are identified and appropriate action is taken (ie the problem is fixed or reported)
all safety procedures are followed.
Assessment method and context
It is preferred that assessment takes place on an industrial extruder in a work environment.
Competence in this unit may be assessed:
by using an appropriate, industrialextruder
in a situation allowing for the generation of evidence of the ability to respond to problems
by using a suitable simulation and/or a range of case studies/scenarios
through a combination of these techniques.
In all cases it is expected that practical assessment will be combined with targeted questioning to assess the underpinning knowledge and theoretical assessment will be combined with appropriate practical/simulation or similar assessment. Assessors need to be aware of any cultural issues that may affect responses to questions.
Assessment processes and techniques must be culturally appropriate and appropriate to the oracy, language and literacy capacity of the assessee and the work being performed.
Specific resources for assessment
This section should be read in conjunction with the Range Statement for this unit of competency. Resources required include suitable access to an operating plant or equipment that allows for appropriate and realistic simulation. A bank of case studies/scenarios and questions will also be required to the extent that they form part of the assessment method. Questioning may take place either in the workplace, or in an adjacent, quiet facility such as an office or lunchroom. No other special resources are required.
Access must be provided to appropriate learning and/or assessment support when required. Where applicable, physical resources should include equipment modified for people with disabilities.