Assembling cores using jigs and fixtures
Overview
This standard identifies the competencies you need to assemble, locate and secure cores, outside the mould cavity, to form core sub-assemblies. The cores will be assembled using both manual and mechanised methods, in accordance with approved procedures.
You will be required to select the appropriate equipment to use, based on the type, size and number of the cores to be assembled and secured. You will be required to check the condition of the cores you receive and to reject any considered as sub-standard, in accordance with the company quality control procedures.
You will, where appropriate, repair minor core defects and dress and apply core coatings. Cores will be assembled using jigs, fixtures and manual methods, to form sub-assemblies, and secured using various methods. On completion of the assembly, you will be expected to carry out final checks to ensure that the quality of the assembled cores meets company standards. Forming and sealing of interconnecting core vents will take place using approved sealing methods and materials. Assembled cores will be passed to the mould closing up area.
Your responsibilities will require you to comply with organisational policy and procedures for the assembling of the cores to form sub-assemblies and to report any problems with the cores, materials or equipment in use 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 carry out.
Your underpinning knowledge will provide a good understanding of your work and will provide an informed approach to the assembly and securing of cores to form sub-assemblies and to the control of metal thickness in assembled cores. You will have an understanding of the different types of materials used to make the cores and of the associated machinery that is used to handle the different sizes of cores. You will understand the different methods of locating the cores in the sub-assembly and the core location devices that are applicable.
You will understand the safety precautions required when carrying out the core assembling 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 relevant instructions, assembly drawings and any other specifications
- ensure that the specified components are available and that they are in a usable condition
- assemble the components in their correct positions, using appropriate methods and techniques
- secure the components using the specified connectors and securing devices
- check the completed assembly to ensure that all operations have been completed and the finished assembly meets the required specification
- 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
- the personal protective equipment and clothing (PPE) to be worn during the activities
- how to obtain the job instructions and interpret the information
- the procedure to be followed in the event of equipment or machine malfunction
- why it is necessary to check the cores prior to commencing the assembly operations
- the defects that can occur in the cores (cracked surfaces, exposed reinforcements, friable surfaces, broken or weak core sections, incomplete cores, damaged or broken core prints and core locations, uncoated cores)
- the actions that are needed when cores are found to be sub-standard
- the storage requirements of cores produced from various types of sands
- the differences in assembly methods using manual freehand, jigs, fixtures and combined methods
- the different processes and machines used to make the cores
- why and how metal thickness checks are made (direct measurement, clay slugs, gauges, templates, jigs and fixtures)
- why different core location devices are used during the assembly activities (such as pins, rebates, prints, diabolos, set-offs, joining cores and dovetails)
- why different methods are used to secure the cores to form sub-assemblies (print locations, adhesives, studs or chaplets, wire ties, pins, interlocking cores and fixtures)
- why cores in the sub-assemblies are held in place prior to inserting them into the mould cavity (using items such as polystyrene, studs or chaplets)
- the effects on casting quality and accuracy of incorrectly located and secured cores
why different types of securing devices are used on ferrous and non-ferrous alloys
why different methods of securing cores in moulds are used when castings are required to be pressure tight or have other operational requirements
- the importance of keeping equipment clean and free from damage, good housekeeping of tools and equipment and maintaining a clean working area
- the extent of your own authority and whom you should report to if you have problems that you cannot solve when assembling the cores to form complete moulds
- how to access, use and maintain information to comply with organisational requirements and legislation
Scope/range
Scope Performance
Assemble and close cores, carrying out all of the following activities:
- confirm that the cores received are complete and free from defects
- adhere to health and safety regulations, systems and procedures to realise a safe system of work
- comply with job instructions, core assembly specifications
- use the correct tools and equipment for the core assembly and preparation activities
- follow the defined core assembly and preparation procedures
- ensure that the completed core assembly meets the required specification for quality and accuracy
- leave the work area in a safe condition on completion of the core assembly activities
Assemble cores to form sub-assemblies, using two of the following:
- freehand manual methods
- fixtures
- jigs
- combined methods
Assemble cores produced from one of the following sands:
- chemically bonded gas activated
- ester silicate bonded
- chemically bonded resin catalyst
- resin bonded heat activated
- oil sand
Apply mould coatings using one of the following methods:
- brush
- spray
- flood
Assemble the cores using both of the following methods:
- manual means
- mechanical means
Determine cast metal thickness, using two of the following methods:
- direct measurements
- gauges
- jigs
- clay slugs
- templates
- fixtures
Assemble a minimum of three cores per assembly, using two of the following location devices:
- pins
- prints
- set-offs
- dovetails
- rebates
- diabolos
- joining cores
- other specific method
Secure the cores together to form complete moulds, using two of the following methods:
- print locations
- wires (tied down or back)
- interlocking cores
- adhesives
- pins
- fixtures
- studs or chaplets
Maintain metal thickness between the assembled cores, using one of the following methods:
- polystyrene
- studs or chaplets
- other specific method
Seal and protect the core vents using one of the following materials:
- adhesive
- flexible mastic
- sand
- plumbago and oil
Complete visual and dimensional checks to the mould, checking all of the following:
- all cores have been assembled
- cores, jigs and fixtures are clean and undamaged
- core vents are sealed and protected
- cores comply with all quality and product specifications