Welding marine materials and structures using the manual oxy/fuel gas welding process
Overview
This standard identifies the competences you need to prepare and operate manual oxy/fuel gas welding equipment, in a marine environment, in accordance with approved welding procedures. You will be required to set up and check the welding equipment and associated workholding and manipulating devices required. In setting up the equipment, you will need to connect all the required regulators/gauges, flashback arrestors, hoses and welding torch ready for use and to set and adjust the gas pressures/welding conditions, in line with the welding procedure specification. You must operate the equipment safely and correctly and make any necessary adjustments to settings in order to produce the welded joints to the required specification. You will be expected to carry out the welding activities in a range of different environmental/access conditions, which will include working at height, working in confined spaces (such as bilge or double bottoms), working in a non-workshop environment and where it is difficult to access the joints to be welded.
Your responsibilities will require you to comply with organisational policy and procedures for the welding activities undertaken and to report any problems with the welding activities or equipment that you cannot resolve, or are outside your permitted authority, to the relevant people. You will be expected to work with a minimum of supervision, taking personal responsibility for your own actions and for the quality and accuracy of the work that you produce.
Your underpinning knowledge will provide a good understanding of your work and will provide an informed approach to applying marine welding procedures and instructions. You will understand the oxy/fuel gas welding process and its application and will know about the equipment, materials and consumables, in adequate depth to provide a sound basis for setting up and operating the equipment, recognising and correcting faults and ensuring that the work output is produced to the required specification. Visual inspection and non-destructive testing of your completed work is implied.
You will understand the safety precautions required when working with the welding equipment. You will be required to demonstrate safe working practices throughout and will understand the responsibility you owe to yourself and others in the workplace.
Performance criteria
You must be able to:
- work safely at all times, complying with health and safety and other relevant regulations, directives and guidelines
- follow the relevant joining procedure and job instructions
- check that the joint preparation complies with the specification
- check that joining and related equipment and consumables are as specified and fit for purpose
- make the joints as specified using the appropriate thermal joining technique
- produce joints of the required quality and of specified dimensional accuracy
- shut down the equipment to a safe condition on completion of joining activities
- deal promptly with excess and waste materials and temporary attachments, in line with approved and agreed procedures
- deal promptly and effectively with problems within your control and report those that cannot be solved
- complete relevant documentation in line with organisational procedures
Knowledge and Understanding
You need to know and understand:
- the safe working practices and procedures to be observed when working with oxy/fuel gas welding equipment (including general workshop and site safety; cylinder handling and storage; appropriate personal protective equipment (PPE); fire and explosion prevention; protecting other workers; safety in enclosed/confined spaces; fume control)
- how to recognise and deal with emergencies and the procedures to be followed (such as methods of safely evacuating and closing down of compartments in the case of fire or other major incident, first aid, fire fighting and resuscitation of personnel)
- statutory requirements; risk assessment procedures, accident procedure and relevant requirements of HASAWA, COSHH and Work Equipment Regulations; safe disposal of waste materials)
- the hazards associated with oxy/fuel gas welding (such as high pressure cylinders and gas supply systems; naked flames; fumes and gases; explosive gas mixtures; oxygen enrichment; spatter; hot slag and metal, grinding and mechanical metal/slag removal; elevated working, enclosed spaces) and how they can be minimised
- the correct handling and storage of gas cylinders (including manual handling and use of cylinder trolley, leak detection procedures, relevant BCGA codes of practice, cylinder identification, gas pressures, cylinder and equipment safety features, emergency shutdown procedures)
- principles of oxy/fuel gas welding, the equipment and its operation (including gas welding principles, supply of compressed gases, characteristics of welding flames, typical equipment, care of equipment, terminology used in gas welding)
- how to extract information required from drawings and welding procedure specifications (such as interpretation of welding symbols; scope, content and application of the welding procedure specification)
- types and classification of filler rods and fluxes; control and storage of consumables
- types and features of welded joints in sheet, plate and tube (including fillet and butt welds, single and multi-run welds, welding positions, weld quality)
- problems that can occur with the welding activities and how these can be overcome (including causes of distortion and methods of control, effects of welding on materials and sources of weld defects; methods of prevention)
- methods of setting up the joint to achieve correct location of components and control of distortion (such as correct joint set-up; cleanliness of materials used; edge preparation; use of jigs/fixtures, manipulators and positioners; tack welding, size and spacing in relationship to material thickness and component size, use of temporary attachments, pre-setting)
- setting up the welding equipment and the checks to be made to ensure that it is safe and ready to use (such as connection of hoses, torch, flashback arrestors, hose check valves and regulators; checking connections for leaks; setting welding parameters)
- the techniques of operating the welding equipment to produce a range of joints in the various joint positions (including selection of nozzle, application of flux, manipulation of torch and filler rods, safe closing down of the welding equipment)
- the organisational quality systems used and the weld standards to be achieved
- weld inspection and test procedures used (including destructive and non-destructive methods)
- personal approval tests and their applicability to your work
- the extent of your own responsibility and whom you should report to if you have problems that you cannot resolve
Scope/range
Scope Performance
Prepare for the manual oxy/fuel gas welding activities, to include carrying out all of the following:
- obtaining the appropriate equipment for the welding activities to be carried out
- correctly handling and storing gas cylinders
- checking the condition of, and correctly connecting, regulators, hoses and valves
- connecting the welding torch and selecting and fitting the correct size nozzle
- fitting a flashback arrestor
- setting appropriate gas pressures
- using the correct procedure for lighting, adjusting and extinguishing the welding flame
- preparing the work area for the welding activities (such as placing welding screens, positioning fume extraction equipment)
- ensuring that the workpiece is correctly set up with regard to specified joint preparation and is secure
- obtaining and wearing appropriate personal protective equipment
Use a range of filler wire to include:
- two different sizes
- two different filler wire properties/composition
Produce welded joints which incorporate the following:
- butt welds
and either
2. fillet welds
Or
3. welds made autogenously (without filler wire)
Produce joints in two forms of specified materials from different material groups, to include the following:
- plate
- sheet (<3mm)
- section
- pipe/tube
- other specific forms
Carry out the welding process under three of the following conditions:
- confined spaces (such as bilge, double bottom)
- at height
- in non-workshop environments
- difficult access
Weld joints according to approved welding procedures in the following BS EN ISO 6947 positions:
- vertical upwards (PF) butt weld
and four other positions chosen from:
2. flat (PA)
3. overhead (PE)
4. vertical downwards (PG)
5. horizontal (PC)
6. horizontal vertical (PB)
7. inclined pipe/tube (H-LO45 or J-LO45)
Produce welded joints which:
- achieve a minimum weld quality equivalent to the level given in the relevant European/International standard (such as BS EN ISO 5817 and EN 30042/ISO 10042) required by the application standard or specification
- meet and verify the required dimensional accuracy, within specified tolerance
Scope Knowledge
Values
Behaviours
Behaviours:
You will be able to apply the appropriate behaviours required in the workplace to meet the job profile and overall company objectives, such as:
- strong work ethic
- positive attitude
- team player
- dependability
- responsibility
- honesty
- integrity
- motivation
- commitment