Grade 12 Preventative maintenance for Gear drives Preventative

Grade 12 Preventative maintenance for Gear drives

Preventative maintenance is defined as: • Care and servicing by personnel for the purpose of maintaining equipment and facilities in a satisfactory operating condition by providing for systematic inspection, detection and correction of emerging failures, either before they occur or before they develop into major defects. • Maintenance, including test, measurements, adjustments and parts replacement, performed specifically to prevent faults from occurring. Mechanical Technology Curriculum Coordination & Support

Two subgroups Preventative maintenance can be divided into two subgroups: • Planned or scheduled maintenance • Condition — based maintenance The main difference between the two subgroups is the determination of maintenance time or the determination of the moment when maintenance should be performed. Mechanical Technology Curriculum Coordination & Support

Planned Maintenance Mechanical Technology Curriculum Coordination & Support

Condition based Maintenance Mechanical Technology Curriculum Coordination & Support

Gear drives • Ensure that gears are properly secured to shafts. • The cleaning and replacement of oil filters. • Excessive noise and wear, vibration and overheating should be reported for expert Mechanical Technology Curriculum Coordination & Support

Mechanical Technology Curriculum Coordination & Support

Lubrication • Lubrication is one of the most important components of a gearbox. • Oil has two main purposes. • It keeps components from wearing and also keeps them cool. • Most gearbox failures can be attributed to improper lubrication. Mechanical Technology Curriculum Coordination & Support

Oil Levels Checking oil levels on a regular basis should be part of your preventive maintenance program. Too little oil can damage gearing and bearings. Too much oil may cause operating temperatures to increase, causing decreased efficiency and reduced oil and seal life. Mechanical Technology Curriculum Coordination & Support

Oil Fill • Many gearboxes are not supplied with oil, so it is important to follow the manufacturer’s recommendations when purchasing oils. • If the wrong type of oil or incorrect viscosity is used, the result can be gear or bearing failures. • If the gearbox is factory-filled with oil, again follow the manufacturer’s recommendations to ensure that additional oil added in the field is compatible Mechanical Technology Curriculum Coordination & Support

Oil Viscosity • Viscosity is a key attribute of the gear oil. • The proper oil viscosity will provide an oil film between meshing gear teeth. • This oil film is very thin and keeps the gear teeth from actually contacting each other. • With too thin of a film or no film, failures such as scoring or wear will occur. Mechanical Technology Curriculum Coordination & Support

Oil Temperature • Temperature changes affect the oil viscosity. • If your application is exposed to extreme temperature variations throughout the year, lubricant viscosity grades should be changed for the season. • For example, an ISO 320 grade viscosity mineral oil is a typical selection for ambient temperatures of 10°C to 50° C. • If this oil is used in the winter and the temperature is -10° C, the oil will be too viscous to flow and properly lubricate components. • Synthetic oils are suitable for a wider temperature range but may have compatibility issues with seals. • Again, it is best to follow manufacturer’s recommendations for oil selection based on ambient temperature. Mechanical Technology Curriculum Coordination & Support

Oil Replacement • Like the oil in your automobile, it is essential that the gearbox oil is replaced regularly. • Oil and grease will break down over time. • As the oil breaks down, it is less effective at maintaining the proper oil film. • Also contaminants that build up in the sump will be flushed out during the oil change. Mechanical Technology Curriculum Coordination & Support

No Maintenance done Failure to conduct preventative maintenance can have very serious or even catastrophic consequences. The most important effects are: • Risk of injury or death(e. g. failed brakes) • Financial loss due to damage suffered as a result of part failure • Loss of valuable production time. Mechanical Technology Curriculum Coordination & Support