Setting automatic spring end grinding machines for production
Overview
This standard identifies the competences you need to prepare and set up automatic spring end grinding machines, such as single end and double end spring grinding machines, in accordance with approved procedures. You will be expected to set up the machines to grind the ends flat, square and to the correct dimensional requirements. This will involve selecting the appropriate workholding devices, and mounting and positioning them to the machine in the correct location for the type of operation being carried out.
You will also be expected to select the appropriate grinding wheels to use, to check them for defects, balance them when appropriate, and to mount and secure them to the machine spindles. You will be expected to prepare the grinding wheels for operation by `trueing up' and dressing the wheels, and creating any necessary relief, as applicable to the operation to be performed. You must set up the appropriate mechanisms, stops and controls for feeds and speeds, as applicable for the particular operations and machine type used. Making adjustments to settings to achieve specification, and solving machine-related problems during production, will also form part of your role.
Your responsibilities will require you to comply with organisational policy and procedures for the spring end grinding machine setting activities undertaken, and to report any problems with the grinding machines, equipment or setting-up activities 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 the setting-up procedures used. You will understand the automatic spring end grinding machine used, and its application, and will know about the workholding devices, grinding wheels, wheel dressing, relevant materials, consumables and setting-up procedures, 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 working with the automatic spring end grinding machines, and with their associated tools and equipment. You will be required to demonstrate safe working practices throughout, and will understand your responsibility for taking the necessary safeguards to protect 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 specifications for the component to be produced
- determine what has to be done and how the machine will be set to achieve this
- mount and set the required workholding devices, workpiece and cutting tools
- set the machine tool operating parameters to achieve the component specification
- check that all safety mechanisms are in place and that the equipment is set correctly for the required operations
- deal promptly and effectively with problems within your control and report those that cannot be solved
Knowledge and Understanding
You need to know and understand:
- how to work safely at all times, complying with health and safety and other relevant regulations, directives and guidelines
- the hazards associated with spring end grinding and how to minimise them and reduce any risks
- how to start and stop the machine in normal and emergency situations
- the importance of ensuring that the machine is isolated from the power supply before mounting grinding wheels and workholding devices
- the importance of wearing the appropriate protective clothing (PPE) and equipment, and of keeping the work area clean and tidy
- the basic operation of the spring end grinding machine, and typical operations that they can perform
- how to handle and store grinding wheels, safely and correctly
- 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 first and third angle drawings, imperial and metric systems of measurement, workpiece reference points and system of tolerancing
- terminology used in spring end grinding, in relation to the activities undertaken
- the range of workholding methods and devices that are used on the spring end grinding machines
- the methods of mounting and setting the springs in the workholding devices, and the tools and equipment that are to be used for this
- the selection of grinding wheels with regard to the type of material being ground and operations being carried out
- how the various types of spring material will affect the feeds and speeds that can be used
- how to check that the grinding wheels are in a safe and serviceable condition
- how grinding wheels are balanced, and the equipment that is used for this
- the methods of mounting and securing the grinding wheels to the machine spindles
- the need for `trueing up' and frequent dressing of wheels to prevent glazing and burning of the spring surface
- how to set up the machines for the particular operations being performed
- the application of cutting fluids with regard to a range of different materials
- the need to conduct trial runs, and to check that the machine is set up and running safely and correctly
- organisational quality control procedures, and the recognition of grinding defects
- problems that can occur with setting up of the grinding wheels, workholding devices and machine operating parameters, and what to do if problems occur
- the importance of completing all relevant documentation on conclusion of the spring grinding activities
- 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 activities during setting up:
- obtain and interpret correctly the documentation for the type of spring to be ground
- 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
- check that the machine and workholding device to be used is in a safe and usable condition
- carry out the setting-up activities, following good practice/approved procedures
- ensure that grinding wheels are correctly dressed/formed and are in a usable condition
- hold components securely, without distortion
- ensure that correctly adjusted machine guards are in place
- leave the machine and work area in a safe and clean condition on completion of the setting-up activities
- Grind components made from two of the following types of material:
- carbon steel
- alloy steel
- nickel based alloys
- stainless steel
- copper based alloy
- titanium and other special material
- other specific material
- Prepare one of the following types of automatic spring end grinding machine in readiness for production:
- single end
- double end
- Use one of the following methods when grinding the springs:
- crash grinding
- down-feed grinding
- Position and secure the springs, using three of the following workholding methods and devices:
- loading plate
- magnetic table
- fixtures
- pots
- bushes
- Select and mount grinding wheels, to include all of the following:
- selecting grinding wheels for specific materials and applications (such as grain size, grade, structure, bond)
- testing wheels for soundness/cracks
- mounting wheels (such as paper washers, flanges, locking pressure)
- balancing wheels, where appropriate
- dressing and `trueing up' grinding wheels
- Set up the spring end grinding machines in accordance with instructions and specifications, to include all of the following, as appropriate:
- mounting and securing the appropriate loading plate/fixture to the machine
- checking springs for cleanliness and freedom from burrs, reaming and edging if required
- loading springs in the fixture, using bushes, where appropriate
- setting guards and safety mechanisms and checking that they operate correctly
- setting the grinding machine to grind one or both ends, as appropriate to the machine type
- setting to give equal tip end thickness
- setting automatic trips and limit switches
- checking that spring length, squareness and finish are to specification
- Use four of the following whilst checking the quality of the springs produced:
- vernier callipers
- vernier protractors
- gauges
- micrometers
- squares
- jigs
- spring testing machines
- electronic measuring equipment
- Carry out checks of the springs, to include all of the following:
- free length
- coil diameter of end
- tip end thickness
- squareness
- solid length
- finish
- Set up automatic spring end grinding machines, to grind spring ends to meet one of the following:
1. BS, ISO or EN standards and procedures
2. customer standards and job requirements
3. company standards and procedures