Ofqual Logo DfES Logo CCEA Logo
The Register of Regulated Qualifications

View Unit : Operating CNC Milling Machines

Unit
Unit Reference Number
D/600/6031
Qualification Framework
QCF
Title
Operating CNC Milling Machines
Unit Level
Level 2
Unit Sub Level
None
Guided Learning Hours
130
Unit Credit Value
39
Date of Withdrawal
SSAs
4.1 Engineering
Unit Grading Structure
Pass
Assessment Guidance

This unit must be assessed in a work environment and must be assessed in accordance with the ‘Common Requirements for National Vocational Qualifications (NVQ) in the QCF’ which can be downloaded from Semta’s website: http://www.semta.org.uk/training_providers__awarding/national_occupational_standard/qca_assessment_requirements.aspx

Additional assessment requirements have been published by Semta. These additional assessment requirements are set down in Semta’s Mechanical Manufacturing Engineering Suite 2 unit assessment strategy which can be downloaded from Semta’s website: http://www.semta.org.uk/training_providers__awarding/national_occupational_standard/qca_assessment_requirements.aspx

Learning Outcomes and Assessment Criteria
Learning Outcome - The learner will:Assessment Criterion - The learner can:
1

1a. Operate CNC milling machines

1.1

Work safely at all times, complying with health and safety and other relevant regulations and guidelines

1.2

Confirm that the equipment is set up and ready for operation

1.3

Confirm that the machine is ready for operation by checking all of the following:

• obtain and use the appropriate documentation (such as job instructions, drawings, quality control documentation)

• 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

• confirm with the machine setter that the machine is ready for production

• where appropriate, seek any necessary instruction/training on the operation of the machine

• ensure that machine guards are in place and are correctly adjusted

• hold components securely, without distortion

• check that the operating program is at the correct start point and the workpiece is clear of the machine spindle

• follow the defined operating procedures and apply safe working practices and procedures at all times

• ensure that ...

1.4

... machine settings are adjusted as and when required (either by themselves or the setter) to maintain the required accuracy

• ensure that the components produced meet the required specification for quality and accuracy

• leave the work area and machine in a safe and appropriate condition on completion of the activities

1.5

Follow the defined procedures for starting and running the operating system

1.6

Operate one of the following CNC milling machines:

• CNC three-axis milling machine

• CNC multi-axis milling machine

• CNC machining centre

1.7

Produce machined components which combine different operations and cover six of the following:

• flat faces

• steps/shoulders

• enclosed slots/recesses

• internal profiles

• holes on pitched circles

• parallel faces

• angular faces

• open ended slots

• external profiles

• holes linearly pitched

• circular/curved profiles

• tapped holes

• special forms (such as concave, convex)

• faces that are square to each other

2

1b. Operate CNC milling machines (continued)

2.1

Machine components made from one of the following types of material:

• ferrous

• non-ferrous

• non-metallic

2.2

Produce components with dimensional accuracy, form and surface texture within all the relevant quality and accuracy standards as is applicable to the operations performed:

• dimensional tolerance equivalent to BS4500 or BS 1916 Grade 9

• surface finish 63µin or

2.3

µm

• reamed and bored holes within H 8

• flatness and squareness within

2.4

” per inch or

2.5

mm per 25mm

• angles within +/-

2.6

degree

2.7

Deal promptly and effectively with error messages or equipment faults that are within their control and report those that cannot be solved

2.8

Monitor the computer process and ensure that the production output is to the required specification

2.9

Use appropriate gauges or instruments to carry out the necessary checks, during production, for accuracy of three of the following:

• dimensions

• squareness

• hole size/fit

• surface finish

• angles

• flatness

• slots

• recesses

2.10

Shut down the equipment to a safe condition on conclusion of the activities

3

2a. Know how to operate CNC milling machines

3.1

Describe the specific safety precautions to be taken when working with CNC milling machines and equipment

3.2

Describe the safety mechanisms on the machine, and the procedures for checking that they are operating correctly

3.3

Explain how to start and stop the machine in both normal and emergency situations and the procedure for restarting after an emergency

3.4

Describe the hazards associated with working on CNC milling machines (such as use of power operated workholding devices, moving machinery, automatic machine operation, handling cutting tools, hot and airborne metal particles), and how to minimise them and reduce any risks

3.5

Describe the importance of wearing the appropriate protective clothing and equipment, and of keeping the work area clean and tidy

3.6

Describe the personal protective equipment to be worn, and where this can be obtained

3.7

Describe the main features of the CNC milling machine, and the accessories that can be used

3.8

Describe the various CNC milling operations that can be performed, and the methods and equipment used

3.9

Describe the operation of the various hand and automatic modes of machine control (such as hand wheels, joysticks, program operating and control buttons)

3.10

Explain how to use the visual display and understand the various messages displayed

3.11

Describe the function of error messages, and what to do when an error message is displayed

4

2b. Know how to operate CNC milling machines (continued)

4.1

Explain how to find the correct restart point in the program when the machine has been stopped before completion of the program

4.2

Explain where to obtain the component drawings, specifications and/or job instructions required for the components to be machined

4.3

Explain how to extract and use information from engineering drawings and related specifications (to include symbols and conventions to appropriate BS, ISO or BSEN standards) in relation to work undertaken

4.4

Explain how to use imperial and metric systems of measurement

4.5

Describe the application of roughing and finishing cuts, and the effect on tool life, surface finish and dimensional accuracy

4.6

Describe the application of cutting fluids with regard to a range of different materials

4.7

Describe the effects of clamping the workpiece in a chuck/workholding device, and how this can cause distortion in the finished components

4.8

Explain how to recognise CNC milling faults, and how to identify when tools need re-sharpening/replacing

4.9

Describe the quality control procedures used, inspection checks to be carried out, and the equipment that will need to be used

4.10

Describe the problems that can occur with the CNC milling activities, and how these can be overcome

4.11

Describe the extent of their own authority and to whom they should report if they have problems that they cannot resolve

Equivalent Units
There are no equivalences to display.
2.4.6.0L