Carrying out proof inspection of sample castings
Overview
This standard identifies the competencies you need to inspect and mark out sample/first-off castings produced from sand or ceramic moulds, dies or investment shells, in accordance with approved procedures. The inspection and marking out will involve the use of a range of measuring instruments, gauges, jigs and marking out equipment. You will be required to select the appropriate instruments and equipment to use, based on the type, size, alloy and inspection requirements of the castings. Both ferrous and non-ferrous castings are covered by this standard. You will ensure that the measuring equipment used is correctly calibrated and meets the necessary quality assurance procedures.
The castings inspected will be circular, square or irregular in shape and will have projections and internal cavities. The profiles will be curved and tapered. You will mark out the castings to the component drawings, using appropriate equipment and tools. You will visually and dimensionally inspect the marked out areas and other external and internal features of the castings, as laid down by the specification. The inspection will generally take place after the castings have received a provisional visual examination and have been fettled and any sub-standard parts have been rejected.
You will use, where appropriate, workholding devices, benches and lifting equipment to manipulate the castings during the proof inspection operation. There could be occasions when larger castings are sited on the floor and you will be expected to manoeuvre these, safely, to complete the work. Castings will be marked up to show any deviations from drawings and specifications. You will produce a report, detailing all non-conforming features and dimensions on the castings. The completed proof inspection report, along with the casting, will be passed to the appropriate person, in accordance with procedures.
Your responsibilities will require you to comply with organisational policy and procedures for the casting proof inspection activities undertaken and to report any problems with the measuring instruments, tools and gauges/jigs in use that you cannot personally 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 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 the proof inspection of various types and size of castings, using marking out equipment and different measuring instruments and methods. You will understand the different instruments and gauges/jigs used during the proof inspection operations and their applications.
The importance of compiling accurate and legible reports will be a key issue in complying with this standard.
You will understand the safety precautions required when carrying out the proof inspection activities and when using the 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, regulations, directives and other relevant guidelines
- follow the correct specification/technique for the product or equipment being inspected
- identify and confirm the inspection checks to be made and acceptance criteria to be used
- carry out the inspections, using appropriate equipment and techniques
- identify any casting defects/flaws or variations from specification
- record the results of the inspections in the appropriate format
- deal promptly and effectively with problems within your control and report those that cannot be solved
- ensure that work records are completed, stored securely and available to others, as per organisational requirements
- leave the work area in a safe condition on completion of the activities, as per organisational and legal requirements
Knowledge and Understanding
You need to know and understand:
- the specific safety precautions to be taken whilst carrying out the activities (including any specific legislation, regulations or codes of practice relating to the activities, equipment or materials)
- the health and safety requirements of the work area and the activities, and the responsibility these requirements place on you
- the hazards associated with the activities, and how to minimise them and reduce risks
- job instructions, specifications and drawings and how to interpret the information
- why sample and first-off castings need to be fully inspected
- the inspection and marking out equipment that is used for the proof inspection activities
- how to check that the measuring equipment is within current calibration dates
- to the importance of keeping the marking out and measuring equipment clean and free from damage, good housekeeping of tools and equipment, and maintaining a clean and tidy working area
- how the castings are prepared for marking out and what mediums are used to enhance the clarity of the marking out
- how to carry out the marking out activities and the need to work from an established datum
- how to carry out inspection checks of the castings (to include checking compliance with drawings/specification, dimensions, flatness, squareness, straightness, angles and tapers, roundness and concentricity, centres of holes or bosses, and profiles)
- the defects/flaws or discontinuities in the castings caused by shrinkage and the moulding process and their effects on first-off inspection activities
- the system of quality control within the company and who is responsible for it
- the extent of your own responsibility and whom you should report to if you have problems that you cannot resolve
- how to access, use and maintain information to comply with organisational requirements and legislation
Scope/range
Scope Performance
Carry out proof inspection of sample castings, including all of the following activities:
- obtain the required inspection equipment and check it is correctly calibrated and in a safe and condition
- adhere to health and safety regulations, systems and procedures to realise a safe system of work
- comply with job instructions, proof inspection specifications
- use the correct tools and equipment for the marking out and inspection activities
- follow the defined inspection procedures and apply safe working practices and procedures at all times
- leave the work area in a safe condition on completion of the activities
Proof inspect castings produced by one of the following processes:
- greensand
- ceramic materials
- chemically bonded gas activated sand
- investment castings
- chemically bonded resin activated sand
- die castings
- resin bonded heat activated sand
- evaporative pattern
- other process (specify)
Proof inspect castings made from one of the following materials
- ferrous alloys
- non-ferrous alloys
- non-metallic materials
Use a range of measuring and marking out instruments, to include both:
- micrometers
- verniers
and seven more of the following: - engineer's rule or tape
- protractor
- profile gauge
- height gauge
- callipers
- radius gauge
- straight edge
- dividers
- jigs or fixtures
- angle plates
- go/no-go gauges
- square
- other specific instruments
Set up, mark out and carry out dimensional checks on castings, to include six of the following features:
- flatness
- roundness
- angle
- squareness
- concentricity
- profiles
- straightness
- taper
- centres
Check, by dimensional inspection, eight of the following casting features:
- overall dimensional tolerances
- incorrect profiles
- sectional variances
- ovality in holes
- swells
- excessive flash
- misplaced cores
- hole centres out of tolerance
- cross joints
- loss of definition/size on machining location points
- thin or thick metal sections
- depth of inclusions on casting surfaces
- lack of metal on surfaces requiring machining
- other feature (specify)
Follow the correct procedure to deal with castings in three of the following categories:
- castings which meet the specification
- castings requiring pattern/die alterations
- castings requiring other inspection methods
- castings requiring further investigation
Complete the inspection activities, to include carrying out all of the following:
- marking up the castings with all relevant information
- recording all the required details in the appropriate format
- handing over the castings and inspection details to the appropriate people