Stowe Consulting Company. OVERVIEW OF TOTAL PRODUCTIVE MAINTENANCE (TPM) . DEFINING TPM .
TOTAL PRODUCTIVE MAINTENANCE
Total Productive Maintenance (TPM) is the process of MAXIMIZING EQUIPMENT EFFECTIVENESS through the EQUIPMENT LIFE CYCLE by coordinating all stakeholders (including those who design, use, and maintain equipment) by involving everyone in the company through TEAM BASED ACTIVITIES with the goal of achieving ZERO LOSSES.
Running Time Actual Output Good Output
Net Operating Time Target Output Actual Output
OVERALL EQUIPMENT EFFECTIVENESS
OEE = AVAILABILITY x PERFORMANCE x QUALITY
+ Breakdowns + Minor Stoppages + Defects & Rework
+ Set-ups + Idling + Start-up
& Adjustments + Reduced Speed & Yield Loss
+ Other changes (Tools, etc)
OVERALL EQUIPMENT EFFECTIVENESS
Running Time: 750 minutes 960/750 = .78125
Net Operating Time 960 minutes
Actual Output 15,500 pieces 15,500/22,000 = .7045
Target Output 22,000 pieces
Good Output 13,400 pieces 14,000/13,400 = .9571
Actual Output 14,000 pieces
AVAILABILITY x PERFORMANCE x QUALITY = OEE
78.15% x 70.45% x 95.71 = 52.69%
PRODUCTIVE MAINTENANCE (Profitable PM) are those activities that assures that equipment is optimally maintained so as to assure it can meet demand in terms of speed, quantity, quality and cost. It includes:
BREAKDOWN MAINTENANCE: Responsive maintenance for breakdowns
PREVENTIVE MAINTENANCE: Preventing Breakdowns by Early Intervention
Daily Cleaning, Inspection and Basic Maintenance
Rebuild / Overhaul
Preventing breakdowns by machine improvements
Facilitate inspection, repair, and use
Document machine activities
BUILDING MAINTENANCE FREE EQUIPMENT
Design of safe, easy and inexpensive machine
Equipment specification and design for maintenance free or easy repair
FILTHY EQUIPMENT INCONSISTENTLY CLEANED
OIL, LUBRICANT, HYDRAULIC LEAKS & AIR LEAKS
ROTATING / MOVING PARTS ENCRUSTED WITH CHIPS, COATING, RAW MATERIAL
WIRES & HOSES TANGLED
MECHANISMS HIDDEN BY BIG COVERS
DISCORGANIZED, SCATTERED, CLUTTERED PARTS, TOOLS &
NO DESIRE TO CHANGE THE STATUS QUO
RESISTANCE ON THE PART OF
MAINTENANCE AND/OR OPERATORS
IGNORING OR MINIMIZING THE PROBLEM
“It isn’t that bad.”
FAILING TO UNDERSTAND GRIT, DIRT &
IMPROPER LUBRICATION SHORTEN EQUIPMENT LIFE
FAILING TO UNDERSTAND ELIMINATING MINOR DEFECTS
YIELD BIG PROFITS
FAILING TO START IMPROVEMENTS WITH RESTORATION
FAILURE TO SUSTAIN THE EFFORT LONG ENOUGH
TO CHANGE THE CULTURE
Equipment can actually have two types of breakdowns:
Function Loss Breakdowns (sometimes known as sporadic breakdowns – where the equipment is unable to function at all.
Function Reduction Breakdowns – where a piece of equipment experiences a a partial loss of function:
- reduced speed due to wear, fatigue, etc.
- produces defects due to no longer being able to hold tolerances, or a mold that has lost integrity, etc.
- minor stoppages due to overheating, misalignment,
Accidental Breakdown Period
ELIMINATING BREAKDOWNS, CONT’D
Equipment doesn’t break down by itself – people break it. How?
Neglecting to do what needs to be done to protect the machine from wear, breakage, misuse, and degradation (rust, untightened bolts, etc. In short, machines fail because of mis-operation and poor maintenance.
Breakdowns happen in three time phases:
Initial Breakdowns after installation that decrease with familiarization and breaking in;
Accidental Breakdowns that occur during a machine’s general operation that remain fairly constant in number and duration; and
Wear Related Breakdowns that gradually increase after a machine has experienced significant length of use.
There are two key types of deterioration:
Natural Deterioration – the result of physical deterioration occurring over time even though equipment might be used correctly; and
Accelerated Deterioration – artificially hastened deterioration caused by people neglecting to do something that needs to be done or by mis-operation of equipment
Breakdowns and defects often occur because someone fails to notice slight problems or abnormal conditions. Some common things to watch for are:
Dirt and grime
Small amounts of wear, scratches
Variable raw materials
ACHIEVING ZERO BREAKDOWNS
PROVIDING THE BASICS
INSPECTING - Develop and use a checklist of things to look at to insure proper maintenance and operation as well as to discover signs of wear or other problems, such as defects, wear, scratches, excessive vibration, misalignment etc.
CLEANING – Keep dirt and grime of and away from equipment to reduce wear and use the cleaning as the time to inspect
LUBRICATING – Check and properly lubricate and make sure all hydraulic and air levels are at the proper pressure. This is a major source of wear along with dirt.
TIGHTENING – make sure basic machine components such as bolts, loose hoses, improper tension of belts, misaligned sprockets or other parts, etc. are checked for looseness or over tightness.
LEARNING HOW NOT TO BREAK EQUIPMENT
LEARNING FROM BREAKDOWNS
We need to study and understand each breakdown so as to learn what needs to be done in order to prevent them in the future. We must identify the root causes and eliminate them. This is another benefit of using the 5 Whys along with the question how can we prevent this from happening again
Autonomous Maintenance are operator based activities that they do to help maintain their own equipment. These are activities, once learned. they can do independent of the maintenance staff. The most common (but not necessarily exclusive) autonomous maintenance activities are:
Daily lubrication, hydraulic top off, etc.
Tightening and alignment
Abnormality inspection, identification, documentation
Tagging of problems that maintenance needs to address