16 Big Losses in Total Productive Maintenance (TPM)
Before knowing 16 Big Losses in Total Productive Maintenance (TPM) you should know what is TPM. TPM is abbreviated as Total Productive Maintenance or Total Productive Management. It is so-called because all the people in an organization are involved in TPM activities. It is very important to learn to develop any organization.
Benefits of TPM:
Periodic and preventative maintenance models can boost your company’s overall production and alleviate downtime It guarantees availability, performance, and quality. Some benefits are mentioned below.
1. Creates Safer work environments by maintaining a proper 5S foundation. 5S foundation means
S: Setting in order,
S: Standardizing, and
2. TPM aims to achieve zero defects, breakdowns, or accidents. Thus it is a Proven impact on efficiency.
3. This is the system of improving staff morale because in this system employees from all levels or departments in the company to fully involved in the same goal with different activities.
4. It increases job satisfaction by establishing a safe workplace. Employee morale and efficient production all come with adopting productive maintenance.
This approach could bring about measurable, lasting benefits such as proactive company culture, reduced changeover, improved quality output, and a longer manufacturing maintenance regime.
16 Big Losses in TPM:
To identify all losses in a process system (man/machine/material), and thus, eliminate them, they have been divided into 16 categories and can be grouped accordingly.
- Breakdown Loss
- Setup and adjustment loss
- Cutting Tool Replacement loss
- Startup Loss
- Minor Stops and Idling Loss
- Speed Loss
- Quality Defect and Rework Loss
- Shutdown Loss
- Management Loss
- Motion Loss
- Line Organisation Loss
- Internal Logistic Loss
- Measurement and adjustment Loss
- Yield Loss
- Energy Loss
- Consumable Loss
Short Briefings of 8 big Equipment losses in Total Productive Maintenance (TPM)
8 big equipment losses in TPM are –
- Breakdown Loss: (unit time e.g. minutes)
The equipment breaks down causing the function of the line or process to stop. Often this is considered as a sporadic failure, typically caused by equipment component failure.
Examples: Bearing failure due to wear, electrical fault, snapped belt.
- Reduction in machine’s capacity to function.
- Time loss
- Reduction in output
- Physical losses caused by the increase in defectives and rework
- Arising from sporadic or chronic failure.
- Setup & Adjustment Loss: (unit time e.g. minutes
This loss occurs during a changeover between products. Set up time is defined as the amount of time taken to change a process over from the last part of a production run to the first good, repeatable part of the next production run. Adjustment within the set up time is often hidden, and involves tweaking settings until optimal run conditions are achieved.
Examples: Changing products, changing packaging, adjusting the feed rate.
- Incurred from the last good product of the previous run comes off the line until changeover, adjustment & test processing are completed.
- The first good product of the next run emerges together with the physical losses (quality loss) created by test processing.
- Cutting tool Replacement Loss: (unit time e.g. minutes)
The time loss incurred swapping any consumable tooling item when it has become worn/ineffective or damaged.
Examples: Time spent replacing saw blades, cutting/grinding tools, and lathe tools.
- Stopping a machine in order to change a cutting tool when it has become worn out or damaged.
- Cutting tool such as grindstone, saw blade, cutter wire or lathe tool.
- Startup Loss (unit time e.g. minutes)
The Loss incurred when production starts throughout the run-up to steady-state operation until processing conditions have been established.
Examples: Time spent warming/cooling equipment to operating temperature, compressor/hydraulic power pack run-up time.
- Minor Stops and Idling Loss (unit time e.g. minutes & Numbers)
It results in stopping and starting and transient problems, which require a machine to be paused or idled for a short period.
Examples: Waiting for a machine to index, emptying a mold during press operation, a sensor fault, or product blockage.
- Speed Loss (unit rate e.g. tonnes per hour)
This loss arises from the difference between the equipment’s design speed and the speed at which it actually operates.
➤ SPEED LOSS = Equipment designed speed – Actual Speed of that equipment
Examples: Line speed reduced due to quality issues or mechanical problems, gaps in the product on conveyors.
- Quality Defect and Rework Loss (Unit – Quantity, time, money)
This is the loss of defective product i.e. Not Right First Time which requires rework, repair or scrap. Examples: Out of spec product, low weight product requiring top-up, poor surface finish, incorrect labelling.
- The physical loss (defective and rework)
- Time loss (time lost by having to reprocess defective product to make it acceptable)
- Shutdown Loss (Unit – Time, quantity)
The loss incurred by deliberately shutting down the equipment within the production plan. Examples: Routine maintenance, periodic overhaul, cleaning, statutory
- The time loss (reduction in output)
- Shutting equipment down deliberately for maintenance
- The physical losses (defective & rework) arising when the equipment is started up again.
5 big Manpower losses in Total Productive Maintenance (TPM)
- Management Loss: (Unit = Time & £)
These are waiting time losses generated by management problems. Examples: Failure to provide materials, spare parts, manpower resource, utilities, work instructions.
- Motion Loss: (Unit = Time & £)
Losses are created due to unnecessary/excessive operator movement and transportation, as a result of poor layout and work organisation. Examples: Walking loss, wasted motion e.g. unnecessary reaching and lifting
- Line Organisation Loss: (Unit = Time & £)
This loss results from a shortage of operators on the line and operators having to work on more equipment than was originally planned. Examples: No additional cover or contingency for break times, training and time spent off the line
- Distribution Loss: (Unit = Time & £)
This loss is the wasted time that is experienced in the incorrect or inefficient delivery of raw materials, packaging or products to and from the factory or the production line. Example: Incorrect delivery of materials from supplier to store, late deliveries, excessive handling of deliveries (double handling)
- Measurement and Adjustment Loss: (Unit = Time & £)
This loss is caused by the frequent measurement and adjustment to prevent the recurrence of problems. Example: Excessive inspection integrated in the process as a result of poor quality and failure to find root cause. Adjustment loss is experienced when adjusting equipment back to the standard after routine cleaning and periodic consumable changes (e.g. labels, film, and ink).
3 big Yield, Energy & Tooling Loss in Total Productive Maintenance (TPM)
- Yield Losses: (Unit = £)
This is the total loss between the input of raw material and the output of finished goods. Examples: over-pack, giveaway, mass balances
- Energy: (Unit = £)
Energy loss is the input energy that cannot be used effectively for processing Examples: Start-up losses, Idling losses.
- Die, Tool and Jig Losses: (Unit =£)
This is the cost of the physical consumption of the spare parts or the refurbishment/maintenance of items that are used on the line. Examples: Cost of spares, cost of replacement and maintenance to tooling, dies, and jigs.
Calculation of OEE ( Overall Equipment Efficiency ) in TPM:
The calculation of OEE relates to the relationship of 7 big Equipment losses & OEE. The calculation formula is given below –
Now the term to calculate overall equipment efficiency (OEE) by the following equation –
Causes of Downtime Losses:
- Setup – adjustment
- Cutting tool replacement
Causes of Performance Losses –
- Minor Stops & idling
Causes of Quality Loss:
- Defectives and rework
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