pull / jit
DESCRIPTION
PULL / JIT. LT6 Training Module. INTRODUCTION. INTRODUCTION. What are Pull & JIT?. An inventory strategy Improves the return on investment of a business by… Reducing in-process inventory Reducing cycle time Driven by signals, or Kanban, to… Make the next part, or Move the next part. - PowerPoint PPT PresentationTRANSCRIPT
PULL / JITLT6 Training Module
INTRODUCTION
What are Pull & JIT?
» An inventory strategy » Improves the return on investment
of a business by…– Reducing in-process inventory – Reducing cycle time
» Driven by signals, or Kanban, to…– Make the next part, or– Move the next part
INTRODUCTION
PULL/JIT| LT6 Training Module
» First used by the Ford Motor Company (early 1900’s)
– "dock to factory floor" – not stored in warehouse, on factory floor
» Adopted by Toyota as part of its Toyota Production System (TPS)» Little space for inventory» Required shortening Set Up Times, through
SMED» Changed assumptions about Economic Lot
Quantity (ELQ)» ELQ fell to 1 unit
» When a part disappeared, a signal to produce or order a replacement.
HISTORY
PULL/JIT| LT6 Training Module
JIT AND PULL, related to……
WHY JIT & PULL
PULL/JIT| LT6 Training Module
But why is it important?
WHY JIT & PULL
PULL/JIT| LT6 Training Module
8 WastesDefects OverproductionWaitingNon-utilized talentTransportationInventoryMotionExtra processing
So…
What’s So Bad About Inventory?
Why Inventory?
PULL/JIT| LT6 Training Module
It HIDES problems
Why Inventory?
PULL/JIT| LT6 Training Module
What’s So Bad About Inventory?
Poor Quality
Work in process inventory level(hides problems)
Unreliable Vendors
Capacity Imbalances
Why Inventory?
PULL/JIT| LT6 Training Module
What’s So Bad About Inventory?
ScrapUnreliable Vendors
Capacity Imbalances
WIP
Lower Inventory level to expose problems, then…» Work on problems by:
– Reducing variability– Eliminating waste– Streamlining production and material flows– Accurate information
JIT
PULL/JIT| LT6 Training Module
So, Pull & JIT are……?
» A management philosophy of continuous and forced problem solving
» Supplies and components are ‘pulled’ through system to arrive where they are needed when they are needed
» Goal: Achieve the minimal level of resources required to add the necessary value in the production system.
» A means of making WASTE easy to see.
JIT
PULL/JIT| LT6 Training Module
JIT Philosophy……
» JIT means the right quantity at the right place and the right time.
» Minimize or eliminate wastes (hidden rocks)
» Simpler is better» Focuses on improving all operations» Flexibility to produce different
models/features with minimal set up
JIT
PULL/JIT| LT6 Training Module
JIT Elements……
» Inventory reduction - exposes problems
» Kanbans & pull production systems» Small lots & quick setups» Uniform plant loading (leveling the
load)» Flexible resources» Efficient facility layouts
JIT
PULL/JIT| LT6 Training Module
JIT Objectives……
» To eliminate waste, by…..– Producing the needed item– at the right time– and the exact quantityAND….– When a problem is identified, fixing it
JIT
PULL/JIT| LT6 Training Module
JIT Principles……
» Produce only what the customer wants
» Produce only at the rate the customer wants
» Produce with perfect quality» Produce with minimum lead time» Produce with no waste of labor,
material or equipment
» Produce with “flow”
Flow
PULL/JIT| LT6 Training Module
What is Flow?
» One piece at a time, opposite of batching
» Minimal distance between operations» Small flexible equipment VS Large
inflexible » Cross Functional VS Departmentalized» Cross Trained operators, easily moved» Produce to the Takt, » Level Loaded production
Enablers
PULL/JIT| LT6 Training Module
What ENABLES JIT to work» Quick set ups (SMED) » Stable processes» Use of standard containers » Doable stable schedules with adequate visibility» TAKT-Time» 5-S efforts » Kaizen Events » Visual controls » Flexible workers » Tools at the point of need » Products designed for manufacturing » Group Technology (product families)» Total Productive Maintenance» Kanban
Benefits
PULL/JIT| LT6 Training Module
What kind of benefits can you expect with JIT?
» Smaller inventories» Shorter lead times» Quicker response to customer demand» Improved quality» Reduced space requirements» Lower production costs» Increased productivity» Greater flexibility» Lower inventory carry costs (%25)
Works Best
PULL/JIT| LT6 Training Module
JIT works best when….
» Trust is present– labor/management– suppliers/consumers
» Individuals are familiar with problem solving» Quality at the source is emphasized» There is agreement over value and waste» Applied in the growth to maturity phases of Product Life Cycle » Products are somewhat “standard”» Standard/fixed pay-rate
– Problems with piece-rate systems» Universal agreement that change is needed
Key Enablers…
PULL/JIT| LT6 Training Module
Quality at the Source
» For JIT to work, quality must be high– There should be no extra inventory to buffer against the
production or use of defective units
» Producing poor-quality items, and reworking or rejecting them is wasteful
» The workers must be responsible for inspection & production quality
» The philosophy is, “NEVER pass along a defective item
Key Enablers…
PULL/JIT| LT6 Training Module
One Piece Flow, Continuous Flow
» The opposite of batch, lot, or mass processing» Product should move (flow) from operation to
operation, only when it is needed, in the smallest increment possible
» One piece is the ultimate (single-piece-flow)» Cross train operators
» Operators float to the bottleneck
Key Enablers…
PULL/JIT| LT6 Training Module
Pull Production, an feature of JIT
» Actual customer demand drives the manufacturing process
» It creates a system of cascading production and delivery signals from downstream demand to upstream production in which nothing is produced by the upstream supplier until the downstream customer signals a need– Big Benefit – Schedule only one point the value stream
» The rate of production for each product is equal to the rate of customer consumption
Key Enablers…
PULL/JIT| LT6 Training Module
Pull Example
Sub
Sub
Fab
Fab
Fab
Fab
Customer Request Final Assy
Vendor
Vendor
Vendor
Vendor
Production
Schedule
LeveledSchedule
A
AC
AB
Key Enablers…
PULL/JIT| LT6 Training Module
Work Balancing / TAKT Time
» Work balancing maximizes operator efficiency by matching work content to TAKT time
» TAKT time is the rate at which customers require your product
» TAKT time is calculated as follows:
Available work time per day
Daily required customer demand in parts per day
Available work time per day
Daily required customer demand in parts per day
Simulation…
PULL/JIT| LT6 Training Module
Let’s see how this works
» YESCO Aviation – Brand new operation– Building planes– 4 Assembly Operators– 1 Material Delivery– 1 Timer– 1 Customer– 1 Manager
Simulation…
PULL/JIT| LT6 Training Module
Let’s see how this works
» YESCO Aviation – Brand new operation– Customer watches for defects– Building and moving 3 at a time (ELQ)– Call Mtl Handler to move product– Customer will take all you can build– Don’t change layout– Colored paper will track “Lead Time”– Will run until enough work in process to capture data
Simulation…
PULL/JIT| LT6 Training Module
Let’s see how this works
» YESCO Aviation – How’d we do?Run #1 Run # 2 Diff
Lot SizeWIP
Lead TimeTotal Run Time 7.25 1.65 0.23
Deiveries 18 10 56%# of People 6 5 83%
SpaceProductivity 0.41 1.21 2.93
Defectives
Simulation…
PULL/JIT| LT6 Training Module
Let’s see how this works
» YESCO Aviation – Run # 2– Move however you like– Lot Size – 1
– Introduce Single Piece Flow discipline
» How’d we do
» Wrap up
Conclusion
PULL/JIT| LT6 Training Module
What’s next?
» Ensure quality» Remove clutter & minimize storage» Reduce setup times» Level load orders, produce to takt » Implement layout changes
– Cellular manufacturing &/or close proximity
» Cross train and teach to float to the bottleneck» Move to pull production» Extend methods to suppliers» Review and improve
Conclusion
PULL/JIT| LT6 Training Module
Q & A