Operating capstan or turret lathes
Overview
This standard identifies the competences you need to carry out turning operations on a capstan or turret lathe, in accordance with approved procedures. You will confirm with the machine setter that the machine is ready for the operations to be performed and that all the required components/materials and consumables are available. You will be expected to produce a range of components that combine a number of different features, such as parallel, stepped and tapered diameters, drilled, bored and reamed holes, internal and external threads.
You will be required to operate the machine in line with safe working practices and approved procedures, to continuously monitor the machining operations and, where necessary, to make minor adjustments or seek the help of the setter to make the required adjustments, in order to ensure that the work output is to the required quality and accuracy. Meeting production targets will be an important issue, and your production records must show consistent and satisfactory performance.
Your responsibilities will require you to comply with organisational policy and procedures for the machining activities undertaken, and to report any problems with the machining activities that you cannot personally resolve, or are outside your permitted authority, to the relevant people. You will be expected to work to instructions, with a minimum of supervision, taking personal responsibility for your actions and for the quality and accuracy of the work that you produce.
Your underpinning knowledge will be sufficient to provide a sound basis for your work, and will enable you to adopt an informed approach to applying machining procedures. You will have an understanding of the capstan or turret lathe turning process, and its application, and will know about the equipment, materials and consumables in adequate depth to provide a sound background for carrying out the activities to the required specification.
You will understand the safety precautions required when working with the machine and its 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.
Setting up of the machine, its tooling and associated workholding devices, is the subject of another standard and is the responsibility of the machine-tool setter.
Performance criteria
You must be able to:
P1 work safely at all times, complying with health and safety and other relevant regulations, directives and guidelines
P2 confirm that the machine is set up and ready for the machining activities to be carried out
P3 operate the machine controls in accordance with safe working practices and operational procedures
P4 produce machined components to the required specification and within the specified dimensional accuracy
P5 carry out quality sampling checks with appropriate gauges/instruments for accuracy at suitable intervals
P6 deal with problems within your control and report those that cannot be solved
P7 complete and store all relevant documentation in accordance with organisational requirements
P8 shut down the equipment to a safe condition on conclusion of the machining activities
Knowledge and Understanding
You need to know and understand:
K1 how to work safely at all times, complying with health and safety and other relevant regulations, directives and guidelines
K2 the safety mechanisms on the machine and the procedure for checking that they function correctly
K3 operation of the machine controls in both hand and power modes, including rapid power of the turret head
K4 how to stop the machine in both normal and emergency situations, and the procedure for restarting after an emergency
K5 the importance of wearing the appropriate personal protective equipment (PPE), and of keeping the work area clean and tidy
K6 where to obtain the component drawings, specifications and/or job instructions required for the components to be machined
K7 how to extract and use information from engineering drawings and related specifications
K8 how to use imperial and metric systems of measurement
K9 the main features of the capstan or turret lathe, and the accessories that can be used
K10 the various turning operations that can be performed, and the methods and equipment used
K11 the effects of backlash in machine slides and screws, and how this can be overcome
K12 the application of roughing and finishing cuts and the effect on tool life, surface finish and dimensional accuracy
K13 the application of cutting fluids with regard to a range of different materials
K14 the effects of clamping the work piece in a chuck/work holding device, and how this can cause distortion in the finished components
K15 how to recognise machining faults, and how to identify when tools need re-sharpening
K16 the quality control procedures used and inspection checks to be carried out, and the equipment that will need to be used for these checks
K17 the issues that can occur with the turning activities, and how they can be overcome
K18 the extent of your own responsibility and to whom you should report if you have problems that you cannot resolve
Scope/range
Scope Performance
1. Apply all of the following during the machining activities:
1.1 obtain and use the appropriate documentation (such as job instructions, drawings, quality control documentation)
1.2 adhere to procedures or systems in place for risk assessment, personal protective equipment and other relevant safety regulations and procedures to realise a safe system of work
1.3 confirm with the machine setter that the machine is ready for production
1.4 where appropriate, seek any necessary instruction/training on the operation of the machine
1.5 ensure that machine guards are in place and are correctly adjusted
1.6 hold components securely, without distortion
1.7 follow the defined operating procedures and apply safe working practices and procedures at all times
1.8 ensure that machine settings are adjusted as and when required (either by yourself or the setter) to maintain the required accuracy
1.9 ensure that the components produced meet the required specification for quality and accuracy
1.10 leave the work area and machine in a safe and appropriate condition on completion of the activities
2. Produce machined components which combine different operations and cover six of the following:
2.1 flat faces
2.2 drilled holes
2.3 internal threads
2.4 chamfers and radii
2.5 parallel diameters
2.6 bored holes
2.7 external threads
2.8 knurls/special finishes
2.9 stepped diameters
2.10 reamed holes
2.11 eccentric features
2.12 grooves/undercuts
2.13 tapered diameters
2.14 profile forms
2.15 parting off
2.16 counter bores
3. Machine components made from one of the following types of material:
3.1 ferrous
3.2 non-ferrous
3.3 non-metallic
4. Use appropriate gauges or instruments to carry out the necessary checks, during production, for accuracy of four of the following:
4.1 diameters
4.2 lengths
4.3 hole size/fit
4.4 depths
4.5 angle
4.6 thread fit
4.7 surface finish
4.8 grooves/undercuts
5. Produce components with dimensional accuracy, form and surface texture within all of the following quality and accuracy standards, as is applicable to the operations performed:
5.1 components to be free from false tool cuts, burrs and sharp edges
5.2 dimensional tolerance as specified in relevant standard
5.3 surface finish 63µin or 1.6µm
5.4 reamed or bored holes within H8
5.5 screw threads BS medium fit
5.6 angles within +/- 1 degree