Unit of competency details

Unit descriptor 

This unit covers powder spraying, using hot and/or cold processes on a range of heavy or light materials.

Application of the unit 

This unit applies to welding of materials using powder spraying equipment where powders are fed through the flame and are deposited onto the surface to be built up or joined.

For remedial action using machining processes other than grinding with grinding wheels (ceramic or other), the appropriate machining units should also be accessed.

Band : A 

Unit Weight : 4 

Prerequisite units 

Path 1 

MEM05004C

Perform routine oxy acetylene welding

MEM12023A

Perform engineering measurements

Employability skills 

This unit contains employability skills.

Elements describe the essential outcomes of a unit of competency.

Performance criteria describe the performance needed to demonstrate achievement of the element. Where bold italicised text is used, further information is detailed in the required skills and knowledge section and the range statement. Assessment of performance is to be consistent with the evidence guide.

ELEMENT 

PERFORMANCE CRITERIA 

1. Prepare work for spray welding

1.1. Spray weld requirements are identified from specifications and/or drawings.

1.2. Work is prepared using appropriate tools and techniques.

1.3. Work is assembled/aligned to specifications as required.

2. Select spray welding equipment and powders

2.1. Appropriate spray welding equipment and consumables for materials and work requirements are selected.

3. Set up spray welding equipment

3.1. Gas setting on spray welding equipment is adjusted to task requirements.

4. Implement distortion prevention/control measures

4.1. Distortion prevention/control measures are identified.

4.2. Appropriate distortion prevention/control measures are applied to minimise and rectify distortion.

5. Spray weld material

5.1. Spray weld is correctly deposited to specification.

6. Inspect spray weld

6.1. Weld area/joints are visually inspected against specification.

6.2. Detected defects are removed with minimum loss of sound material.

REQUIRED SKILLS AND KNOWLEDGE 

This section describes the skills and knowledge required for this unit.

Required skills 

Look for evidence that confirms skills in:

• preparing materials
• selecting equipment and powders
• setting up equipment
• spray welding material
• identifying defects in welds
• rectifying weld defects
• applying techniques for distortion prevention and rectification
• cleaning welds
• reading and interpreting routine information on written job instructions, specifications and standard operating procedures. May include drawings
• following oral instructions
• entering routine and familiar information onto proformas and standard workplace forms

Required knowledge 

Look for evidence that confirms knowledge of:

• correct welding equipment, hoses, tips, hand pieces and filler powder
• procedures and processes for material preparation
• procedures and processes for joint preparations
• causes of distortion for materials within the scope of this unit
• causes of defects and methods of rectification
• use and application of personal protective equipment
• safe work practices and procedures
• relevant hazards and control measures related to the competency

EVIDENCE GUIDE 

The evidence guide provides advice on assessment and must be read in conjunction with the performance criteria, required skills and knowledge, range statement and the Assessment Guidelines for the Training Package.

Overview of assessment 

A person who demonstrates competency in this unit must be able to powder spray, using hot and/or cold processes, on a range of heavy or light materials. Competency in this unit cannot be claimed until all prerequisites have been satisfied.

Critical aspects for assessment and evidence required to demonstrate competency in this unit 

Assessors must be satisfied that the candidate can competently and consistently perform all elements of the unit as specified by the criteria, including required knowledge, and to be capable of applying the competency in new and different situations and contexts.

Context of and specific resources for assessment 

This unit may be assessed on the job, off the job or a combination of both on and off the job. Where assessment occurs off the job, that is the candidate is not in productive work, then an appropriate simulation must be used where the range of conditions reflects realistic workplace situations. The competencies covered by this unit would be demonstrated by an individual working alone or as part of a team. The assessment environment should not disadvantage the candidate.

This unit could be assessed in conjunction with any other units addressing the safety, quality, communication, materials handling, recording and reporting associated with welding using powder spraying equipment or other units requiring the exercise of the skills and knowledge covered by this unit.

Method of assessment 

Assessors should gather a range of evidence that is valid, sufficient, current and authentic. Evidence can be gathered through a variety of ways including direct observation, supervisor's reports, project work, samples and questioning. Questioning techniques should not require language, literacy and numeracy skills beyond those required in this unit of competency. The candidate must have access to all tools, equipment, materials and documentation required. The candidate must be permitted to refer to any relevant workplace procedures, product and manufacturing specifications, codes, standards, manuals and reference materials.

Guidance information for assessment 

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. Bold italicised wording, if used in the performance criteria, is detailed below. 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) may also be included.

Welds 

Fillet and butt in all positions

Prepared 

Preheating, setting up of jigs, fixtures, clamps, etc., joint preparation e.g. bevelling

Equipment 

AC or DC welding machines

Materials 

Steels, carbon steels, cast iron, etc. or non-metallic materials (plastic/nylon)

Distortion prevention 

Preheating, setting up of jigs, fixtures, clamps, etc.

Defects 

Porosity, slag inclusions, discontinuities, lack of penetration, undercut

Removal of defects 

Oxy acetylene and air arc equipment, grinding devices

Unit sector 

Co-requisite units 

Competency field 

Fabrication