Producing replacement components for maintenance activities
Overview
This standard identifies the competences you need to produce replacement components resulting from maintenance activities, in accordance with approved procedures. You will produce these components using manual machining techniques, such as milling, turning, grinding, shaping/slotting, drilling/boring, combined with hand fitting techniques. You will be expected to produce components that require you to use a range of different machines, and this will involve setting up the workholding arrangements, workpiece and machine tooling.
You will also be expected to use a range of hand tools, portable power tools, and shaping and fitting techniques, that are appropriate to the type of material and operations being performed. These activities will include such processes as hand sawing, band sawing, filing, drilling, chiselling, threading, and off-hand grinding. The components produced will, typically, be such items as shafts, bushes, sleeves, distance pieces/spacers, packings, plates, studs, slides, pulleys, gear blanks, handles, levers or linkages.
Your responsibilities will require you to comply with organisational policy and procedures for the machining activities undertaken, and to report any problems with the machines, tooling, materials or activities that you cannot personally resolve, or that are outside your personal responsibilities, to the relevant people. You will be expected to work with minimal supervision, taking personal responsibility for your own actions, and for the quality and accuracy of the work that you carry out.
Your underpinning knowledge will provide a good understanding of your work, and will provide an informed approach to applying replacement component manufacturing procedures and instructions. You will understand the machining and fitting processes used, and their application, and will know about the machine, tooling, ancillary equipment, materials and consumables, in adequate depth to provide a sound basis for carrying out the activities, correcting faults and producing the components to the required specification.
You will understand the safety precautions required when working with the machines and their associated tools and 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 legislation and other relevant regulations, directives and guidelines
- follow instructions and any relevant specifications to produce the component
- produce the required components using appropriate manufacturing methods and techniques
- check that the finished component meets the requirements and make any necessary adjustments
- deal promptly and effectively with problems within your control and report those that cannot be solved
- complete and store all relevant replacement component documentation in accordance with organisational requirements
Knowledge and Understanding
You need to know and understand:
- the safe working practices and procedures to be followed whilst carrying out the machining activities
- the safety mechanisms on the machine, and the procedure for checking that they are operating correctly
- how to operate all the machine controls, in both hand and power modes, and how to stop the machine in case of an emergency
- the importance of wearing appropriate protective clothing and equipment (PPE) and of keeping the work area clean and tidy
- how to obtain and interpret drawings, specifications, manufacturers' manuals and other documents needed in the manufacturing process
- how to take measurements and produce working sketches of parts to be made, where no drawings are available
- how to use filing, scraping and lapping to achieve the required surface finish (such as the various types of files/scrapers, checking that file/scraper handles are in good condition, types of lapping mediums)
- how to cut external threads using hand dies, and the method of fixing and adjusting the dies to give the correct thread fit
- how to determine the drill size for tapped holes and the importance of using the taps in the correct sequence
- how to produce a sliding or mating fit
- how to select saw blades for different materials and different operations
- the use of vice jaw plates to protect the workpiece from damage
- how to correctly use hand power tools and specialist equipment (such as electrical, pneumatic, lifting equipment)
- how to check that portable power tools, extension cables and air hoses are free from damage and are in a safe, tested and usable condition
- the operating requirements of the machine tools and accessories being used (such as guards, workholding devices, taper turning attachments, steadies, dividing heads, specific statutory regulations)
- the various shapes and types of tooling that can be used (such as solid high-speed tooling, brazed tip tooling, interchangeable tipped tooling)
- how to handle and store tools and equipment safely and correctly
- factors which affect the selection of cutting feeds and speeds, and the depth of cut that can be taken (such as workpiece rigidity, machine condition, type of tooling being used, material type, finish and tolerance required)
- the application of cutting fluids with regard to a range of different materials and processes
- the techniques and implications of clamping a workpiece in a chuck/work holding device (such as safely secured for the process, not causing distortion in the finished components)
- how to recognise machining faults and identify when tools need re-sharpening/dressing
- types and applications of grinding wheels, methods of mounting, and why some wheels require balancing
- the specific pieces of legislation that apply to your activities
- the methods that can be used to position the workpiece in relation to the cutting tools
- the effects of backlash in the machine slides, and how this can be overcome
the problems that can occur with the machining and fitting activities, and how these can be overcome
the extent of your own authority and to whom you should report if you have problems that you cannot resolve
Scope/range
Carry out all of the following during the machining activities:
- obtain and use the correct drawing, sketch or sample/damaged component to be replaced
- adhere to procedures or systems in place for risk assessment, COSHH, personal protective equipment and other relevant safety regulations and procedures to realise a safe system of work
- check that machines used are in a safe and usable condition
- check that cutting tools and equipment are in a serviceable condition
- ensure that workpieces are held securely without distortion
- apply safe and appropriate manufacturing techniques at all times
- use correctly adjusted machine guards and safety devices
- report or take action with regard to any problems that arise
- complete and store all relevant replacement component documentation in accordance with organisational requirements
Produce replacement components using a range of hand fitting methods, to include five from the following:
- hand sawing
- band/power sawing
- filing
- drilling
- chiselling
- threading external
- off-hand grinding
- scraping
- threading internal
- lapping
- cleaning and polishing
- etching/pickling and drying
Produce replacement components using two of the following machining processes:
- turning
- milling
- grinding
- drilling
- spark/wire erosion
- shaping or slotting
Produce replacement components which cover five of the following features:
- external diameters
- faces that are square to each other
- drilled holes
- internal diameters
- angular/tapered surfaces
- bored holes
- flat faces
- threads
- reamed holes
- parallel faces
- circular/curved/radial profiles
- concave or convex form
- steps/shoulders
- slots/recesses
- special forms
Produce components which comply with all of the following quality and accuracy standards:
- dimensional tolerances are to specification/replacement component requirements
- the surface finish complies to replacement component requirements
- components are free from false tool cuts, burrs and sharp edges
- components are fit for purpose
Produce replacement components from two different types of material from:
- low carbon steel
- brass
- high carbon steel
- bronze
- stainless steel
- plastic/synthetic
- cast iron
- composite
- aluminium
- steels or alloys