Lean Manufacturing Terminology
Lean has a language of its own. We have separated lean
terms into six subdivisions: General Terms, Workflow,
Workplace Organization, Workplace Simplification, Process
Improvement, and Measures.
- Waste: Any aspect of a
task or activity that does not add value.
- Value Stream: All tasks
and activities needed to transform input materials and
information into an output.
- Current State: The
current or existing view of the workflow.
- Product Family: A
grouping of products using similar processing methods.
- Future State: A
potential improved view of the workflow.
- JiT: Just-in-time means providing what is needed,
when it is needed, in the quantity it is needed.
- One-piece Flow: A
practice where product is moved from one workstation to the next
one piece at a time without allowing inventory to build up
- Takt Time: The rate at
which the customer uses a product. It is calculated by dividing
the total daily operating time by the total daily customer
- Bottlenecks: The step in
a process line that limits the throughput of the entire process
- Pull vs. Push: Two
diametrically opposite scheduling philosophies. Push
manufacturing schedules are dictated by a formal production
schedule where a new lot is pushed onto the first step of the
process. With pull manufacturing, a customer order triggers the
start of a new lot; typically empty kanbans pull new production
from the prior process step.
- Monuments: Equipment
that is too costly or disruptive to move is considered a
- Kanbans: A visual
signal, typically a re-order card or container that triggers a
pull manufacturing system.
- The 5S's: A formal
approach to organizing the workplace.
- Work Cell: A
cross-functional process line typically including equipment to
process products (or product families) from start to finish.
- TPM: Total productive
maintenance, an approach that leads to increased equipment
availability by reducing downtime due to failure and unplanned
- Mistake-Proofing: A
mistake prevention approach.
- SMED: Literally "Single
Minute Exchange of Dies." It stands for set-up reduction, an
approach that minimizes the time the process is down being
changed over from one product to another.
- Visual Workplace: Use of
visual controls and visual displays to help employees maintain
control of their work areas and assess performance at a glance.
- DFA/DFM: Design for
Assembly and Design for Manufacturability techniques that
improve manufacturing productivity.
- Kaizen: Continuous
improvement on top of continuous improvement.
- Problem-Solving Process:
A formal, structured approach to solving a problem such as the
8D Process or DMAIC.
- Kaizen Event: A focused,
short-term event to make immediate improvements.
- FMEA: Failure Mode and
Effects Analysis, a technique used to assess risk in a process
or a product design.
- QFD: Quality Function
Deployment, a technique used to identify the "Voice of the
Customer" and match customer requirements and technical
- DOE: Design of
Experiments, a family of statistical improvement techniques.
- COQ: Cost of Quality, a
quantification of the cost of poor quality.
- Set-Up Time: The time it
takes to set-up a process to produce the next product, measured
from the last good part of the prior lot to the first good part
of the new lot.
- On-Time Delivery: A
measure of the success rate of delivering (or shipping) on the
- Lead Time: The time
quoted to customers (usually in days or weeks) between the date
of purchase and the shipment date.
- Inventory Turns: the
number of times the value of inventory is turned over in a year;
12 turns means that the value of inventory is turned 12 times
per year or once per month.
The number and extent of tools to help lean efforts is probably
unending but these four tools are vital.
- Value Stream Mapping: A
graphical representation of all tasks and activities needed to
transform input materials and information into an output.
- The 5S's: A structured
approach to clean and organize the workplace.
- Set-Up Reduction:
Reducing the time to set-up or change-over a process.
- TPM: Total Productive Maintenance:
Techniques to improve equipment reliability by
reducing the frequency of breakdowns and failures.
Some of the major lean techniques include:
- Workflow Analysis:
Analyzing the physical layout of a process flow with the intent
of reducing travel distances, eliminating redundancies,
improving communication and quality.
- Layouts & Work Cell Design:
Using the results of value stream mapping and workflow analysis
to improve the macro and micro layout of the process.
- Simulated Continuous Flow:
With a step-wise batch operation, simulating a continuous
process with small lot sizes (as small as a lot size of 1),
elimination of WIP, and direct feed of each process step from
its prior step.
- Pull Scheduling:
Starting a new lot with an order from a customer.
- Kanban: A visual signal,
typically a re-order card or container that triggers a pull
- Load Balancing: Matching
or adjusting the throughput rate of all steps in a workflow.
Improving the throughput rate of the process bottleneck.