Elements and Performance Criteria

This competency unit includes the butt welding of polyethylene (PE) pipeline components using hydraulic activated welding machines. The end applications include pipelines used for transmission of gaseous and water based fluids.

It also includes the operation of all relevant ancillary equipment.

Specifications include national standards for materials (AS/NZS 4130, and AS/NZS 4131), workplace specifications and instructions, and government codes and regulations.

This competency requires the use of:
hydraulic activated butt welding machines, and pipe supports
measurement devices including pressure gauges, timers, temperature probes, callipers and computer based pressure/temperature monitors
cleaning fluids and spray equipment
calculators
relevant safety equipment
comprehensive work instructions.

Typical hazards include:
hazardous cleaning fluids
pipe material handling
heavy stationary and moving machinery, cutting and heating components.

Routine problems include:
variable PE materials, and as supplied pipes
equipment malfunction, wear and tear
variable field site conditions.

All operations are required to be performed in accordance with standard procedures and work instructions.

Essential knowledge and enterprise requirements:
Knowledge and understanding of PE materials and pipeline components as described in national standards to recognise welding compatibility and suitability.
Knowledge of detailed work instructions necessary to perform butt welding, and the ability to implement within required parameters to attain required quality outcomes.

Competence includes the ability to:
identify materials being used
calculate welding parameters for individual machines and pipeline components
maintain and adjust operating conditions in welding machine
set up and maintain safe working environment
operate welding machine within required parameters
assess quality of completed joints
identify and rectify fault causes arising from machine operation and component variables
establish and maintain quality records
as relevant for the practical completion of work required.

Critical aspects
Consistent achievement of required weld quality standards is critical.

Language, literacy and numeracy requirements
Read material which is sequenced for instructions, explanations, information or opinions.
Write short and simple messages about routine tasks or activities, or complete forms.
Use hands-on real-life materials and pictures/diagrams based on personal experience and prior knowledge.
Use several pieces of related mathematical information.
Read, write and speak whole numbers and money sums, recognise and interpret simple fractions, decimals and percentages, use simple data, grid references.
Uses simple grammatical forms and vocabulary to give instructions, give explanations, ask questions and express viewpoints.
Clarify intended meaning by asking for repetition when listening, and varying speed and changing tone or emphasis when speaking.
Use strategies such as providing verbal and non-verbal feedback in order to show interest or attitude.

Assessment method and context
Current competence in this unit may be assessed by the combination of:
practical workshop welding exercises
completion of a short answer questionnaire
completion of weld parameter calculations
in-course workshop style discussions.

Resource implications
Hardware:
This section should be read in conjunction with the range of variables for this unit of competency. Resources required for training institutions include suitable powered workshop facilities and classroom space with visual support aids, specialised hydraulic activated welding machines, measuring and monitoring control devices for pressure and temperature, together with necessary PE component samples and material ancillaries.

Software:
This section should be read in conjunction with the range of variables for this unit of competency. Resources required for training institutions include comprehensive training resource manuals, and support visual aids derived from field experience activities. Presenters require specialised training and field experience in PE materials, pipeline components, welding technology and material testing.