Unit of competency details

Unit descriptor 

This unit covers preparing materials, selecting and setting up the welding equipment, carrying out advanced gas tungsten arc welding (GTAW), inspecting for and correcting defects, and maintaining the weld records.

Application of the unit 

This unit applies to welds associated with a range of structural sections and/or plate and/or pipe for general fabrication. Weld quality would typically conform to Australian Standard 1554 Structural Purpose, Bureau Det Norse Verticas or equivalent.

Band : A 

Unit Weight : 4 

Prerequisite units 

Path 1 

MEM05007C

Perform manual heating and thermal cutting

MEM05019D

Weld using gas tungsten arc welding process

MEM05049B

Perform routine gas tungsten arc welding

MEM05051A

Select welding processes

MEM05052A

Apply safe welding practices

MEM09002B

Interpret technical drawing

MEM12023A

Perform engineering measurements

MEM18001C

Use hand tools

MEM18002B

Use power tools/hand held operations

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 welding materials and equipment

1.1. Welding equipment is prepared.

1.2. Welding equipment appropriate to task requirements is assembled and adjusted correctly and safely.

1.3. Materials are prepared to achieve the required weld specification.

2. Weld joints to code requirements using advanced GTAW

2.1. Weld requirements are interpreted correctly,

2.2. Welds are deposited correctly to specifications.

2.3. Appropriate distortion prevention measures are selected for the weld type and material and distortions are rectified as required.

3. Assess weld quality and rectify faults

3.1. Weld joints are visually inspected against specifications.

3.2. Defects are removed using appropriate methods for the given task.

3.3. Weld records are correctly completed and maintained.

REQUIRED SKILLS AND KNOWLEDGE 

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

Required skills 

Look for evidence that confirms skills in:

• welding to conform to Australian Standard 1554 Structural Purpose, Bureau Det Norse Verticas or equivalent
• interpreting technical drawings and weld specifications relating to advanced GTAW
• using hand and power tools to prepare and weld material using GTAW
• using measurement and numeracy skills relating to advanced GTAW and preparation
• selecting equipment and consumables appropriate to task
• using visual identification of faults/defects

Required knowledge 

Look for evidence that confirms knowledge of:

• in-depth knowledge of the properties and characteristics of a wide range of materials
• requirements to conform to Australian Standard 1554 Structural Purpose, Bureau Det Norse Verticas or equivalent
• weld procedures and requirements
• different welder identification systems such as numbering, bar coding, paint coding, letter stamps
• safe welding practices
• use and application of personal protective equipment for GTAW
• hazards and control measures related to GTAW

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 prepare materials, select and set up the welding equipment, carry out the GTAW welding and inspect for and correct defects and maintain welding records. 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 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 performing advanced welding using gas tungsten arc welding process (GTAW) 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.

Equipment 

AC or DC welding machines, gases, settings, electrodes and related equipment

Materials 

Low carbon, cast iron, stainless and low alloy steel, aluminium

Prepared 

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

Welds 

Fillet and butt in all positions

Distortion prevention measures 

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

Defects 

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

Appropriate methods 

Oxy acetylene, air arc equipment and grinding devices

Weld records 

Proformas and other standard workplace forms

Unit sector 

Co-requisite units 

Competency field 

Fabrication