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.

Where the assessee does not currently possess evidence of competency in PMBPROD254 Operate an open mill blender, it may be co-assessed with this unit.

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:

identify critical materials properties and process characteristics in relation to the process requirements and the end product

make adjustments to the process as required

identify and take appropriate action on problems and potential problems.

Consistent performance should be demonstrated. For example, look to see that:

the process runs consistently and smoothly, with the minimum need for human intervention.

all safety procedures are always followed.

Assessment method and context

Assessment will occur on an industrial mill and will be undertaken in a work-like environment.

Competence in this unit may be assessed:

using an appropriate industrial mill requiring demonstration of start-up, operation and shutdown procedures

in a situation allowing for the generation of evidence of the ability to recognise, anticipate and 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.

This describes the essential skills and knowledge and their level required for this unit.

Application of knowledge of the materials, equipment and process sufficient to recognise material and equipment conditions which may lead to out of specification production.

Knowledge of organization procedures, quality requirements at each stage of production and relevant regulatory requirements (eg quality system and standards, current operating standards) and the ability to implement them within appropriate time constraints and work standards.

Application of the knowledge of managing risks using the hierarchy of controls applied to compound materials using an open mill blender. Application of approved hazard control and safety procedures and the use of PPE in relation to handling materials, equipment operation and cleanup.

Knowledge as a basis for solving processing and material problems, including:

products, materials and material characteristics

behaviour of materials in relation to key process variables

quality requirements at each production stage

function and operating principles of equipment, machine components and ancillary equipment, including mechanical, hydraulic, pneumatic, electrical and electronic principles which affect machine operation

impact of key process variables such as speed/speed difference, temperature, nip, bank size, and time on product quality and production output

impact of material properties, such as rubber nerve, filler volume and dryness, resin tack and accelerator scorch on mixing

phases of the mixing process such as ban forming, nerve breaking, additive incorporation and homogenisation

the importance of machine set-up and start-up procedure for effective processing of materials

impact of variations in raw materials and equipment operation in relation to final product

changes to materials at various stages of production

waste management and importance of re-using non-conforming materials

polymer properties and their interactions with process conditions

relationships between polymer properties and process conditions

changes to polymer properties to better suit process requirements

product problems related to polymer properties

product problems related to process conditions

adjustments to process conditions to meet polymer and product requirements.

Skill to identify the range of possible causes of product faults including:

low/high plasticity

scorch

strength

hardness.

Competence also includes the ability to:

plan own work, including predicting consequences and identifying improvements

maintain output and product quality using appropriate instruments, controls, test information and readings

identify and describe own role and role of others involved directly in the process

identify factors which may affect product quality or production output and appropriate remedies

identify when assistance is required to solve problems.

Language, literacy and numeracy requirements

This unit requires the ability to read and interpret typical product specifications, job sheets and material labels as provided to operators.

Writing is required to the level of completing workplace forms and production reports.

Basic numeracy is required, eg to determine how many 2 kg, 3 kg and 5 kg bags are needed to make up a requirement for 50 kg.

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 the operation of open mill equipment in the plastics and rubber sectors. It includes the operation of all relevant additional equipment where that equipment is integral to the process.

While primarily intended for the mixing of rubber compounds using an open mill it may also apply to the mixing of plastics or other materials and may apply where mixing and blending is incidental to the operation such as slabbing of striping.

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.

Tools and equipment

This competency includes use of equipment and tools such as:

open mill and its major components

hand tools used in the process, eg mill knives

material loading equipment used for loading of raw materials, eg stock loaders and conveyors, overhead crane arms and hooks

relevant personal protective equipment.

Hazards

Typical hazards include:

nip hazards

cut hazards

dusts/vapours

slip and fall (such as caused by scrap of spilled materials)

temperature(such as hot rubber)

hazardous materials (including curatives and accelerators, plasticisers, fillers)

manual handling hazards.

Problems

'Anticipate and solve problems' means resolve a wide range of routine and non-routine problems, using product and process knowledge to develop solutions to problems which do not have a known solution/a solution recorded in the procedures..

Typical process problems may include:

power failures

incorrect machine adjustments

incorrect quantities of materials

incorrect blending times

equipment breakdowns

worn rolls

short scorch products

forming the initial band

adjusting bank size for efficient mixing.

Typical product problems many include:

variations in materials

contamination of materials

lack of a homogeneous product.

Appropriate action for problems outside of area of responsibility may be reporting to an appropriate person.

Appropriate action for solving problems within area of responsibility includes asking questions and seeking assistance from appropriate persons/sources.

Variables

Key variables to be monitored include:

temperatures

speed (including difference in speed between rolls)

nip pressures

colour

cycle time/process timing

product/stock/material flow and quality

product weight and output rate

product integrity and general conformance to specification and quality sample.

Copy and paste from the following performance criteria to create an observation checklist for each task. When you have finished writing your assessment tool every one of these must have been addressed, preferably several times in a variety of contexts. To ensure this occurs download the assessment matrix for the unit; enter each assessment task as a column header and place check marks against each performance criteria that task addresses.

Observation Checklist