Producing composite mouldings using resin transfer moulding techniques
Overview
This standard identifies the competences you need to setup and produce composite mouldings using resin transfer moulding techniques, in accordance with approved procedures. You will be required to use appropriate drawings, specifications and documentation to produce various mouldings, using the correct resin transfer moulding production techniques.
You will be expected to prepare a range of tooling, apply release agents and prepare composite materials. You will be expected to setup the resin transfer moulding equipment to produce a range of mouldings incorporating a variety of features. Mouldings produced will include laminates and sandwich structures, using a range of resin, fibre and core materials.
Your responsibilities will require you to comply with organisational policy and procedures for the setup and production activities undertaken, and to report any problems with the equipment setup, production activities or materials that you cannot personally resolve, or that 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 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 resin transfer moulding techniques and procedures. You will understand the setup and production techniques used, and their application, in adequate depth to provide a sound basis for carrying out the activities, correcting faults, and ensuring that the work output is to the required specification.
You will understand the safety precautions required when carrying out the moulding 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 and other relevant regulations, directives and guidelines
- follow the correct component drawing or any other related specifications for the component to be produced
- determine what has to be done and how this will be achieved
- obtain and prepare the appropriate tools, equipment and materials
- set the equipment operating parameters required for the resin transfer moulding operation
- carry out the moulding activities using the correct methods and techniques
- check that the equipment operates within the operating parameters set
- produce mouldings to the required specification
- check that all the required operations have been completed to specification
- check the quality of the mouldings by visual inspection
- complete and store all relevant documentation in accordance with organisational procedures
- deal promptly and effectively with problems within your control and report those that cannot be solved
- leave the work area in a safe and appropriate condition on completion of the activities
Knowledge and Understanding
You need to know and understand:
- the health and safety precautions to be taken, and procedures used, when working with composite materials, consumables, tools and equipment in the specific work area
- the hazards associated with carrying out resin transfer moulding techniques, and with the composite materials, consumables, tools and equipment used, and how to minimise these and reduce any risks in the work area
- the protective equipment (PPE) that is needed for personal protection and, where required, the protection of others
- the specific environmental conditions the must be observed when producing composite mouldings (such as temperature, humidity, fume/dust extraction systems and equipment)
- how to extract and use information from engineering drawings and related specifications (to include symbols and conventions to appropriate standards) in relation to work undertaken
- how to interpret drawings/ lay-up manuals, imperial and metric systems of measurement, workpiece reference points and system of tolerancing
- the quality procedures used in the workplace to ensure production control (in relation to currency, issue, meeting specification), and the completion of such documents
- the conventions and terminology used for resin transfer moulding techniques (such as material identification, lay-up specifications, resin viscosity, injection pressure, injection rate, resin/catalyst ratios, resin and fibre weights/volumes, gel times, exotherm)
- the safety mechanisms on the machine, and the procedure for checking that they function correctly
- the operation of the machine controls, and how to stop the machine in an emergency
- the parts and functions of the resin injection machines, injector heads and sensors (to include machine controls; hydraulic, pneumatic and electricity supplies; material delivery and flushing systems)
- the various machine operating parameters that may require adjusting prior to resin transfer moulding activities (such as pressure, flow rate, quantities, catalyst ratios), and how these are achieved
- the effects that changes to theses settings will have on the quality of the components produced
- the different types of resins, reinforcement, catalysts, accelerators and additives used, and their applications
- the different types of fibre materials and preforms, their combinations and applications
- the different core and insert materials, and their merits
- the visual identification of both raw and finished composite materials
- different types of production tooling used for producing composite mouldings, and their applications
- the identification and rectification of defects in production tooling
- methods of preparation for moulds and tooling (including the correct selection and use of surface sealers and release agents)
- methods for handling, preparation, positioning and application of the reinforcing fibres and fabrics
- mixing ratios for gel coats, resins, accelerators and catalysts, and the associated working times
- the tools and equipment used in the resin transfer moulding activities, and their care, preparation and control procedures
- the problems that can occur during the resin transfer moulding process (including defects such as contamination, incomplete saturation, pressure/vacuum leaks, flow restrictions)
- the different methods and techniques used to cure composite mouldings including cure cycles and the need for monitoring
- procedures and methods used for removing mouldings from production tooling
- the identification of defects in the composite mouldings (such as dry patches, print through, voids, contaminants)
- the care and safe handling of production tooling and composite mouldings throughout the production cycle
- the production controls used in the work area, and actions to be taken for unaccounted items
- how the composite component relates to its own quality documents and the production tooling used
- the extent of your own responsibility and to whom you should report if you have problems that you cannot resolve
Scope/range
Scope Performance
- Carry out all of the following during the moulding activities:
- obtain and use the appropriate documentation (such as job instructions, drawings, material data sheets, specifications, equipment setting-up documentation, planning and quality control documentation)
- 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
- provide and maintain a safe working environment for the setting and moulding activities
- obtain and check that all tools and equipment to be used are correct for the operation to be carried out and are in a safe and usable condition
- follow safe practice/approved setting and moulding techniques at all times
- plug injection and vent holes on completion of resin injection where required
- clean/flush mixing and injection equipment after use
- return all tools and equipment to the correct location on completion of the moulding activities
- segregate and dispose of waste materials using the correct procedure
- Prepare the machine for use, to include carrying out all of the following:
- ensure all machine services are connected and operational (such as electrical, pneumatic, vacuum)
- ensure there are sufficient raw materials available and that they meet the component specification (such as resin, catalyst and flushing solvent)
- set up the machine operating conditions to suit the moulding being produced, including alarm conditions
- check the injector head and cleaning cycles function correctly
- check that all the machine controls function correctly including pressure and vacuum sensors where applicable
- set the resin and/or mould tool heating arrangements where applicable
- Prepare the machine for use, to include setting all of the following where applicable:
- injection pressure
- Injection flow rate
- injection quantity
- catalyst percentage
- mould vacuum level
- peripheral seal vacuum level
- Prepare the tooling for production, to include carrying out all of the following:
- check that tooling is correct and complete
- clean tooling and remove resin build-ups
- check for surface defects
- correctly apply sealers/release agents
- clean and store tooling suitably after use
- Produce composite mouldings incorporating five of the following features:
- internal corners
- external corners
- double curvature
- concave surface
- convex surfaces
- return surfaces
- joggle details
- nett edges
- other specific feature
- Produce composite mouldings, using one type of resin from:
- epoxy
- phenolic
- bismaleimide
- cyanate ester
- other specific type
- Produce composite mouldings, using two types of fibre from:
- polyethylene
- glass
- aramid
- carbon
- other specific type
- Produce composite mouldings, using six types of reinforcement/preform from:
- uni-directional
- chopped strand
- tissues/veils
- woven
- braids
- multi-axis/stitched
- tapes
- knitted
- stitched perform
- 3D knitted perform
- braided perform
- RTM fabric
- RTM fabric/core
- other specific type
- Produce composite mouldings, using two types of core materials from:
- wood
- expanding core
- nomex honeycomb
- aluminium honeycomb
- syntactic core
- foam
- other specific type
- Produce composite mouldings, using three types of mould clamping system:
1. threaded fasteners
2. toggle clamps
3. latch clamps
4. vacuum clamping
5. hydraulic press
6. electric press
7. other specific type
- Visually inspect a number of sample or trial mouldings, and identify two of the following:
1. mouldings which meet the required specification
2. mouldings which have defects
3. mouldings that require further investigation
- Produce composite mouldings in compliance with all of the following quality and accuracy standards:
1. company standards and procedures
2. dimensionally accurate within specification tolerances
3. has an appropriate surface finish and is free from defects or surface blemishes