MCE 509 Mechanical Maintenance Flashcards

Comprehensive vocabulary flashcards covering key definitions, techniques, calculations, maintenance types, TPM pillars, OEE losses, scheduling tools, and MHE systems from MCE 509 Mechanical Maintenance.

Maintenance

The discipline and profession of applying engineering concepts to the optimization of equipment, procedures, and departmental budgets to achieve better maintainability, reliability, and availability of equipment.

Breakdown Repairs

Repairs carried out on equipment or machinery that has broken down during the course of normal operation.

Overhaul

Repairing and maintaining a piece of equipment or machinery to restore it to working condition.

Rebuild

Restoring a piece of equipment to working condition after it has reached the end of its working life or after it has been damaged.

Service

Routine operations to keep equipment functioning effectively.

Modification

Small adjustments, changes, or additions to a piece of equipment to improve output.

Inspection

A physical examination or review to assess equipment functionality and performance, which may encompass taking measurements or performing tests.

Replacements

Changing out a piece of equipment or its components when it has reached the end of its useful life.

Salvage

Replacing an item with a new one to bring the system back into operation when equipment cannot be repaired or brought to the desired level of performance.

Planned Maintenance

Maintenance that is organized and makes use of records for a predetermined plan.

Preventive Maintenance (PM)

Care and servicing carried out at predetermined intervals with prescribed criteria to keep equipment and facilities in a satisfactory operational state and reduce the probability of failure.

Breakdown Maintenance

Maintenance where repair is undertaken only after the failure of a system.

Opportunistic Maintenance

A maintenance approach that utilizes an opportunity, which may arise at any time, to perform maintenance.

Emergency Maintenance

Maintenance performed to bring a failed machine or facility to a safe and operationally efficient condition.

Routine Maintenance

Activities that are repetitive and periodic in nature, such as lubrication, cleaning, and small adjustments.

Corrective Maintenance

Maintenance performed to correct or restore a failed unit, executed through data collection, root cause identification, finding the best solution, and implementation.

Running Maintenance

Activities carried out while the machine or equipment is running, performed before actual preventive maintenance activities take place.

Shutdown Corrective Maintenance

Maintenance activities performed when the production line is in a total stoppage situation.

Design-Out Maintenance

Activities to eliminate the cause of maintenance, simplify tasks, or raise machine performance by redesigning machines and facilities vulnerable to frequent failure.

Predictive Maintenance

Activities that detect changes in the physical condition of equipment (signs of failure) to carry out maintenance work maximizing service life without increasing failure risk.

Failure Rate

The time rate of change of the probability of failure, denoted by $\lambda(t)$, providing physical information on which factor controls failure behavior.

The Bathtub Curve

A graphical representation describing the relative failure rate of an entire population of products over time, consisting of infant mortality, normal life, and wear-out periods.

Infant Mortality Period

The initial 'running in' period of a product's life cycle characterized by a high but decreasing failure rate due to design or manufacturing errors, defective parts, or material defects.

Useful Life Period

The normal life period where the failure rate is at its lowest and remains constant, driven by random external events rather than inherent internal defects.

Wear Out Period

The phase occurring toward the end of product life with an increasing failure rate caused by old age, material fatigue, corrosion, contact wear, and insulation failure.

Reliability

The probability that a product, system, or component will perform without failure under specified conditions for a specific period of time.

Mean Time Between Failures (MTBF)

The average operating time between two successive failures of a repairable system, calculated as $\text{MTBF} = \frac{1}{\lambda}$ when the failure rate is constant.

Mean Time To Failure (MTTF)

The average time to failure used for non-repairable components or items such as filament lamps, fuses, resistors, and capacitors.

Availability Ratio

The portion of total time a machine should function relative to the time it actually functions, calculated as $\text{AR} = \frac{U}{U + D}$ where $U$ is uptime and $D$ is downtime.

Maintainability

The combined qualitative and quantitative characteristics of material design and installation enabling operational objectives with minimum resource expenditure under specified maintenance environments.

Infrared Thermography (IRT)

The application of noncontact infrared detection instruments in short wave ($3\text{ to }5\,\mu m$) and long wave ($8\text{ to }15\,\mu m$) bands to identify temperature differences and thermal anomalies.

Total Productive Maintenance (TPM)

A holistic approach to equipment maintenance striving for perfect production with no breakdowns, no small stops or slow running, no defects, and no accidents.

5S Foundation

A clean and well-organized work environment foundation for TPM consisting of five elements: Sort, Straighten, Shine, Standardize, and Sustain.

Autonomous Maintenance

The TPM pillar placing responsibility for routine maintenance, such as cleaning, lubricating, and inspection, in the hands of equipment operators.

Planned Maintenance (TPM Pillar)

The TPM pillar that schedules maintenance tasks based on predicted or measured failure rates to reduce unplanned stop time.

Quality Maintenance

The TPM pillar that designs error detection and prevention into production processes and applies Root Cause Analysis to eliminate recurring sources of quality defects.

Focused Improvement

The TPM pillar where small groups of employees work together proactively to achieve regular, incremental improvements in equipment operation.

Overall Equipment Effectiveness (OEE)

A metric identifying the percentage of planned production time that is truly productive, calculated as $\text{OEE} = \text{Availability} \times \text{Performance} \times \text{Quality}$.

Six Big Losses

The six primary causes of productivity loss in manufacturing: Unplanned Stops, Setup and Adjustments, Small Stops, Slow Running, Production Defects, and Reduced Yield.

Critical Path Method (CPM)

A deterministic project scheduling technique using a single time duration estimate based on judgment to determine early/late start and finish times and the critical path.

Program Evaluation Review Technique (PERT)

A probabilistic project scheduling technique incorporating three time estimates ($O_i$, $P_i$, $m_i$) and modeling activity durations using a beta distribution.

Optimistic Time ($O_i$)

In PERT analysis, the time required to complete an activity if execution goes extremely well.

Pessimistic Time ($P_i$)

In PERT analysis, the time required to complete an activity under the worst possible conditions.

Most Likely Time ($m_i$)

In PERT analysis, the time required to complete an activity under normal operating conditions.

Economic Order Quantity (EOQ)

An inventory model used to determine the exact order quantity that minimizes total inventory costs, balancing ordering costs and storage or carrying costs.

FSN Analysis

Inventory classification based on frequency of issues/use, categorizing items into Fast moving, Slow moving, and Non moving.

SDE Analysis

Inventory classification based on procurement lead-time, categorizing spare parts into Scarce ($> 6\text{ months}$), Difficult ($15\text{ days to }6\text{ months}$), and Easily available ($< 15\text{ days}$).

VED Analysis

Inventory classification based on equipment criticality and production downtime loss, categorizing spare parts into Vital, Essential, and Desirable.

ABC Analysis

Inventory classification based on annual consumption value applying Pareto's principle, categorizing spares into Class A (70% value, 10% items), Class B (20% value, 20% items), and Class C (10% value, 70% items).

HML Analysis

Inventory classification based on unit price, categorizing spare parts into High Cost, Medium Cost, and Low Cost.

Insurance Spares

Spare parts used to replace failed identical parts in operating equipment with very high downtime penalty costs, which do not become obsolete until the parent machine is retired.

Capital Spares

Vital spare parts for critical equipment characterized by high unit cost, very high stock-out cost, and low consumption quantity over equipment lifetime.

Overhaul Spares

Spare parts that must be replaced every time equipment is disassembled and reassembled.

Wear and Tear Spares

Spare parts experiencing regular wear during operation that require replacement after a definite number of operating hours.

Single-Minute Exchange of Die (SMED)

A setup time reduction program aimed at minimizing Availability Loss caused by setup and adjustments.

Chain Hoist

A lifting device commonly used for lighter loads in workshops and warehouses, requiring regular inspection of the load chain for elongation, twisting, or corrosion.

Wire Rope Hoist

A lifting device used for heavy-duty lifting in industrial applications, requiring inspections for broken strands, kinks, crushing, and proper drum and sheave alignment.

Pneumatic Hoist

A hoist powered by compressed air used in hazardous environments like chemical plants, requiring clean air filters, proper air pressure, and clean exhaust ports.

Electric Hoist

A hoist widely used for precise lifting in factories and warehouses, requiring motor inspection, limit switch testing, and routine wiring checks.

Overhead Crane (Bridge Crane)

A crane used in factories to handle heavy loads within enclosed environments, requiring track alignment checks, girder inspection, and cable line monitoring.

Mobile Crane

A versatile crane used on construction sites, requiring hydraulic system checks, tire or track inspection, boom and jib examination, and LMI safety testing.

Tower Crane

A crane with a fixed structure used for high-rise construction projects, requiring base bolt checks, mast inspection, slewing bearing lubrication, and wind-speed monitoring.

Crawler Crane

A heavy-lifting crane with a tracked undercarriage providing stability on uneven terrain, requiring track alignment and engine cooling system checks.

Gantry Crane

A crane supported by legs that move on a track or rail system, requiring leg structural checks, rail cleanliness, and wheel bearing lubrication.