Application
This unit describes the performance outcomes required to carry out grinding operations on engine crankshafts to specific under sizes. It involves preparing for the task, determining crankshaft damage and required repair action, preparing and using grinding machines to grind crankshafts to specifications, tolerances and workplace requirements, and completing workplace processes and documentation.
It applies to those working in the automotive service and repair industry. The crankshafts include those in vehicles from all sectors of the industry.
No licensing, legislative, regulatory or certification requirements apply to this unit at the time of publication.
Elements and Performance Criteria
Elements Elements describe the essential outcomes. | Performance Criteria Performance criteria describe the performance needed to demonstrate achievement of the element. Where bold and italicised text is used, further information is detailed in the range of conditions section. |
1. Prepare to grind crankshaft | 1.1 Job requirements are determined from workplace instructions 1.2 Crankshaft is cleaned and inspected and condition reported 1.3 Information is sourced, procedures and methods are analysed, and appropriate crankshaft grinding machine and equipment are selected for the crankshaft 1.4 Hazards associated with the work are identified and risks are managed 1.5 Tools and measuring equipment are selected and checked for serviceability 1.6 Crankshaft grinding wheel is prepared according to machine manufacturer specifications and tolerances, and workplace procedures 1.7 Crankshaft is measured to determine under size and tolerances, including journal diameters and sizes of grind 1.8 Crankshaft is positioned in grinder in correct direction of rotation, and clamped according to manufacturer specifications and workplace procedures |
2. Grind crankshaft big end bearing journals | 2.1 Chuck offsets are set according to the stroke of crankshaft 2.2 Crankshaft grinder wheel head position is set according to machine manufacturer procedures 2.3 Constant measuring gauge and steady rest are positioned on big end journal taking into account position of oil hole 2.4 Crankshaft is ground at correct rotational speed for crankshaft material and diameter according to safety requirements, and following machinery safe operating procedures 2.5 Crankshaft is measured to ensure compliance with specifications and tolerances 2.6 Grinding operations are completed to required specifications and tolerances according to safety requirements, and following machinery safe operating procedures |
3. Grind crankshaft main bearing journals | 3.1 Crankshaft is removed from grinder 3.2 Chucks are centralised for main bearings and counterweights are adjusted 3.3 Crankshaft is refitted to grinder in correct direction of rotation, and is clamped according to manufacturer specifications and workplace procedures 3.4 Datum is set in relation to crankshaft rear flange and nose 3.5 Crankshaft grinder wheel head movement is set according to manufacturer procedures 3.6 Constant measuring gauge and steady rest are positioned on main bearing journal taking into account position of oil hole 3.7 Crankshaft is ground at correct rotational speed for crankshaft material and diameter according to safety requirements, and following machinery safe operating procedures 3.8 Crankshaft is inspected to ensure compliance with specifications and tolerances 3.9 Grinding operations are completed to required specifications and tolerances according to safety requirements, and following machinery safe operating procedures |
4. Finish crankshaft grinding | 4.1 Oil holes are chamfered and dressed 4.2 Journals are linished with correct grade of belt and in right direction of rotation and required finish 4.3 Flange ends and seal areas are faced 4.4 Crankshaft is examined and measured according to manufacturer specifications and tolerances, and workplace procedures 4.5 Crankshaft is cleaned according to workplace procedures 4.6 Bright surfaces are treated with rust prevention solution and crankshaft is prepared for further process or storage according to workplace procedures |
5. Complete work processes | 5.1 Final inspection is made to ensure finished work complies with workplace requirements and crankshaft is presented ready for use or storage 5.2 Work area is cleaned, waste and non-recyclable materials are disposed of, and recyclable material is collected 5.3 Tools and equipment are checked and stored according to workplace procedures 5.4 Workplace documentation is processed according to workplace procedures |
Evidence of Performance
Before competency can be determined, individuals must demonstrate they can perform the following according to the standards defined in this unit’s elements, performance criteria, range of conditions and foundation skills:
grind one crankshaft of an in-line petrol engine with at least four cylinders.
Evidence of Knowledge
Individuals must be able to demonstrate knowledge of:
work health and safety (WHS) and occupational health and safety (OHS) requirements relating to grinding crankshafts, including procedures for:
selecting and using personal protective equipment (PPE) for using grinding machines and chemical cleaning and lubricating agents
identifying hazards associated with rotating grinding machines
manual handling techniques relating to grinding crankshafts
types, characteristics and limitations of crankshaft grinding machines, including:
hand-held machines for oil hole dressing
types and grades of grinding wheels, including grit grades
dismantling procedures for crankshafts, including:
numbering and removing counterweights
drive gears
oil seal sleeves and dowels
cleaning and inspection procedures, including:
chemically cleaning crankshafts, including methods of avoiding damage to nitride and Tufftride crankshafts
identifying crankshaft material
identifying heat treatment process, including nitriding, Tufftriding and induction hardening
identifying radius treatment, including deep fillet rolling, radius rolling and shot peening
checking alignment of crankshaft in V blocks
measuring journals against specifications and identifying damaged journals
testing procedures for crankshaft, including:
crack testing coil shot and end shot
testing hardness of journals
procedures for preparing crankshaft grinding wheel, including:
wheel preparation, including selecting wheel to suit radius and journal width of crankshaft
dressing procedures for wheel, including:
types of diamonds for front and radius dressing
procedures for dressing wheel to suit crankshaft radius
procedures for dressing front of wheel
procedures for big end grinding, including:
setting crankshaft rotation speed according to crankshaft material and big end diameter
setting crankshaft grinder wheel head position
setting chuck offsets for big end bearings and adjusting counterweights to suit
fitting crankshaft in correct direction of rotation and ensuring that critical surfaces are not damaged by the chuck
measuring journal diameters during grinding with constant measuring gauge
procedures for adjusting crankshaft grinder to suit main bearing journal grinding, including:
removing crankshaft from grinder
fitting crankshaft in correct direction of rotation
setting datum in relation to rear flange and nose for main bearing grinding
procedures for main bearing journal grinding, including:
setting crankshaft rotation speed according to crankshaft material and journal size
setting crankshaft grinder wheel head position
measuring journal diameters during grinding with constant measuring gauge
procedures for finishing journal grinding, including:
chamfering and dressing oil holes
linishing journals according to grade of belt, required finish, and rotational direction
setting up and facing flange ends and seal areas
final grinding inspections of crankshaft, including:
journal surface finish
taper, ovality, barrelling, and hourglass
grinding chatter
burning of radius and journals
methods of correcting faults
procedures for removing crankshaft from grinder and checking crankshaft for straightness in V blocks using dial indicator
requirements of Australian standards relating to engine reconditioning, including:
AS 4182 Automotive repairs – Code of practice for reconditioning reciprocating spark ignition engines
AS 4427 Automotive repairs – Code of practice for reconditioning reciprocating compression ignition engines
post-grinding operations, including rust protection of machined surfaces.
Assessment Conditions
Assessors must satisfy NVR/AQTF assessor requirements.
Competency is to be assessed in the workplace or a simulated environment that accurately reflects performance in a real workplace setting.
Assessment must include direct observation of tasks.
Where assessment of competency includes third-party evidence, individuals must provide evidence that links them to the crankshaft grinding that they have carried out, e.g. repair orders.
Assessors must verify performance evidence through questioning on skills and knowledge to ensure correct interpretation and application.
The following resources must be made available:
automotive repair workplace or simulated workplace
workplace instructions
manufacturer crankshaft specifications
AS 4182 Automotive repairs – Code of practice for reconditioning reciprocating spark ignition engines
AS 4427 Automotive repairs – Code of practice for reconditioning reciprocating compression ignition engines
crankshaft from an in-line petrol engine with at least four cylinders requiring grinding
engine crankshaft grinding machine
precision measuring equipment, including:
dial indicators
inside and outside metric and imperial micrometers.
Foundation Skills
This section describes those language, literacy, numeracy and employment skills that are essential to performance and are not explicit in the performance criteria.
Skills | Description |
Learning skills to: | locate appropriate sources of information efficiently. |
Reading skills to: | interpret crankshaft specifications from workshop literature interpret machinery safe operating procedures from operating manuals. |
Writing skills to: | legibly and accurately fill out workplace documentation to record measurements. |
Numeracy skills to: | interpret numerical information in manufacturer specifications, workshop literature, and machinery dials, gauges and computer readouts use basic mathematical operations, including addition and subtraction, to: convert metric dimensions to imperial, and imperial dimensions to metric calculate tolerances and clearances. |
Planning and organising skills to: | select best tooling option for the work and sequence procedure to reduce time and material wastage. |
Technology skills to: | use metric and imperial precision measuring equipment. |
Range Statement
This section specifies work environments and conditions that may affect performance. Essential operating conditions that may be present (depending on the work situation, needs of the candidate, accessibility of the item, and local industry and regional contexts) are included. Bold italicised wording, if used in the performance criteria, is detailed below.
Cleaning and inspecting crankshaft must include: | following procedures for chemically cleaning nitride and Tufftride crankshafts inspecting crankshaft, including: coil shot end shot hardness alignment bend thread condition key way condition seal running surfaces condition rear flange condition nose gear condition. |
Preparation must include: | selecting wheel to suit radius and journal width procedures for dressing wheel. |
Safety requirements | work health and safety (WHS) and occupational health and safety (OHS) requirements, including procedures for: selecting and using personal protective equipment (PPE) for using grinding machines and chemical cleaning and lubricating agents identifying hazards associated with rotating grinding machines manual handling techniques relating to grinding crankshafts. |
Examining and measuring crankshaft must include: | checking journals for: acceptable surface finish taper ovality barrelling hourglass grinding chatter and journal burning checking crankshaft for straightness in V blocks using a dial indicator. |
Sectors
Technical - Manufacture
Competency Field
Mechanical Miscellaneous