SMEDQuick Changeover Contents Introduction Background and History Components

SMED-Quick Changeover

Contents • Introduction • Background and History • Components and Implementation – Changeover and Changeover Time – Traditional Setup – SMED (Single Minute Exchange of Dies) – SMED Process Steps – Ideas for Improvement • Knowledge Check 2

Introduction • Quick Changeover is one of the core concepts of lean manufacturing • A rapid and efficient way of converting a process from running the current product to running the next product • Also known as “single minute exchange of dies” (SMED) – derived from the desire to change over any process within minutes instead of hours • Reduces the waste of inventory by creating shorter production runs that better align with customer demand 3

Background and History • Developed in the late 1950’s and early 1960’s by Shigeo Shingo, chief engineer of Toyota • Land costs in Japan were very high, therefore it was not feasible to store large inventories of vehicles • Quick Changeover provided a solution to the economic lot size problem of traditional manufacturing, which promoted large lot sizes 4

Components and Implementation • Changeover and Changeover Time • Traditional Setup • SMED (Single Minute Exchange of Dies) • SMED Process Steps • Ideas for Improvement 5

Changeover Defined • Definition: – Changeover is the total process of converting a machine or line from running one product to another 6

Changeover Time Defined • Definition: – Changeover time is the total elapsed time between the last unit of good production of the previous run, at normal line efficiency, to the first unit of good production of the succeeding run, at full line efficiency. 7

The Objective • Objective: – Reduce changeover from hours to single minutes 8

Time Out to Roll Your Eyes • It’s all been said before… – – – – “Be serious…” “Can’t really happen…” “What are you smoking…” “Our operation is unique…” “That’s only in low-tech molding or stamping…” “We can’t move any faster…” “We’re already the best at what we do…” 9

Before SMED • Typical changeover: 1 – 2 hours 10

After SMED Typical changeover: minutes. . . Or seconds 11

Real World Examples • 3000 -ton sheet metal stamping press – – Before: 4 hours After: 3 minutes Improvement: 98. 7%, or a factor of 80 Now the same press can make multiple parts (hoods and doors in this case) for the Camry, only what is needed for the next hour of production. • 400 -ton LIM molding press with 16 -cavity tool – Before: 3 hours – After: 18 minutes – Increase in effective capacity equal to 5, 184 additional parts 12

More Examples 13

Benefits of Setup Reduction • Better quality – Very defined setup processes • Lower cost – Less scrap and inventory • Better flexibility – Rapidly change from product to product • Better worker utilization – Less time spent on setup or waiting for the run to start • Shorter lead time and more capacity • Less process variability 14

SMED is Continuous Improvement • It is a customer-driven requirement. Customers are demanding: – Product and service diversity – Lower costs – Higher reliability and quality. • So – – – organizations must: Produce smaller lots, more frequently. Expand the scope and diversity of products Reduce quality defects. 15

Traditional approach • Setup is given and fixed • Therefore, – Use highly skilled setup personnel – Minimize product variety – Combine lots – Make large batches 16

Another way • Setups CAN be improved! • Small lot production REQUIRES short setups • Setup time reduction of 90% and more is common 17

6 “Traditional” Setup Steps 1. 2. 3. Preparation – Ensures that all the tools are working properly and are in the right location. Extraction – The removal of the tooling, raw material, and support equipment after the production lot is completed. Mounting – The placement of the new tool, support equipment, and raw material before the next production lot. 4. Establishing Control Settings – Setting all the process control settings prior to the production run. 5. First Run Capability – This includes the necessary adjustments required after the first trial pieces are produced. 6. Setup Improvement – The time after processing during which the tooling, machinery is cleaned, identified, and tested for functionality prior to storage. 18

The SMED Process • Step 1 – Observe and record. • Step 2 – Separate internal and external activities. • Step 3 – Convert internal activities to external activities. • Step 4 – Streamline all activities. • Step 5 – Document internal and external procedures. 19

Step 1: Observe and Record • Team-work – Recorder • Record overall duration (from last product to first good product). • Video recorders work very well • Describe the change (from what to what? ). – Timers • Time each step – Fact collectors • Breakdown the steps into actions – as much detail as possible. • Use a layman to ask uninformed questions – challenge the “accepted norm”. 20

Step 1 • Timers. – Aim to have 10 -20 steps for each changeover. – Record the elapsed time. Calculate the step time later. 21

Step 1: Fact collectors. • Have a number of fact collectors to ensure elements are not missed. • One fact per Post-it – write clearly, be concise. • Record everything. – E. g. For the “remove guards” step – fact collectors may record the following elements: 1. Walk to control panel 2. Switch machine off 3. Wait for flywheel to stop 4. Get spanner from toolbox 5. Remove 3 hex bolts 6. Get Allen key 7. Remove 5 Allen bolts 8. Remove guard 9. Walk to rear of machine 10. Place guard on the floor 11. Walk to front of machine 22

Step 2: Separate internal and external activities • Internal set-up activities. – Elements in the changeover which can only be done when the machine is stopped. • External set-up activities. – Elements that can be performed when the machine is running. 23

Step 3: Convert internal to external • Study each internal step and ask if it could be external. – Common issues: • Dies in remote storage racks. • Spanners not available. • Raw material checks. • Lifting equipment not available. • Ask why the remaining internal steps can’t be external. – Re-examine the true function of each step. – Common issues: • Cold dies – using material to heat the dies. • No record of settings. 24

Step 4: Streamline all activities • Analyze the activity, and discuss all possible ways of improving the step. • Study the external activities as well as the internal activities. • Common issues: – Fastenings – Are bolts needed? If so remember that only the last turn tightens a nut or bolt. – Standardize bolt heads. – Standardize die heights. – Equipment and material availability and accessibility. 25

Step 5: Document the procedures • Write down the new internal and external procedures. • Fill in an action sheet to ensure that the new procedures can be achieved. • Review the whole activity to determine “What went well? ”, “What went badly? ” and changes that the team would make before the next SMED activity. 26

Non-Manufacturing Example • Directory inquiries in New York handles 5. 5 million calls per day at an average time of 22 seconds per call. • Changed to asking “Directory inquiries, what listing? ” instead of “Directory inquiries, what listing please? ” – New Yorkers often broke into the “please” with their request anyway • Reduced peak call center requirements from 87 operators to 72 operators. 27

Non-Manufacturing Example (cont. ) • A call to NY directory inquiries is no longer a real time experience. • Digitized responses saved 5 seconds in the 1980’s. • Now your request is recorded and delivered to the next available operator (while you were speaking he was helping a previous customer). • The recording is processed through a computer program which removed all of the pauses or silences and the “Uhms and Ahs”. • The software then speeds up the recording by 20% • Peak operator requirements dropped by another 23% 28

Priorities • Eliminate all unnecessary elements of changeover • Externalize all possible elements • Simplify what remains • Measure, measure 29

Ideas for Improvement • The following slides have several potential areas for improvement. 30

Combining equipment functionality • Involves standardizing the equipment (parts, tooling, processes) based on commonality between setups to reduce the number of setup steps and cycle times. The common setup parts were identified and replaced with this jig/holder combination. By using these fixtures, the parts are automatically centered and adjusted for height and flatness as a part of External setupnot Internal setup. Notice how different quantities of the same part can be setup with the same fixture. Also, these setups can occur while the machine is running. 31

Waste associated with finding, replacing, motion Tooling supplies are clearly labeled Tooling supplies are neatly assigned a unique location. 32

One Step Fastening Bolt attachments requires 32 complete turns for each bolt or screw (1 for each thread) to fasten this bolt and die to a machine. This clamp attachment requires one step to attach the die to a machine. This magnetic clamp attachment requires one step to attach the die to a 3000 ton press machine. 33

Common Problems Solved • Problem: “only the last turn tightens a nut or bolt, and the first one loosens it”. • Solution 1: Key-holes. Fasten here Attach and remove plate here 34

Common Problems Solved • Problem: “only the last turn of a nut or bolt tightens it and only the first one that loosens it”. • Solution 2: Split Thread Method. Three grooves cut into male and female threads. Bolt inserted by aligning the grooves and sliding into position. Bolt tightened by a one-third turn. Note: the bolt needs to be longer to preserve the area of effective friction. 35

Common Problems Solved • Problem: Dies are different heights - operators have to change the clamping bolts. • Solution: Shim the smaller die to equalize the height If center height of the tool is important, shim top and bottom 36

Common Problems Solved • Problem: Waiting for tooling to reach elevated temperatures. • Solutions: – Pre-heat ovens, electric or steam heating. – Use the coolant water from the machine to pre-heat the dies. – Use a transfer jig which will allow the electrical and coolant connections to be made off-line and to bring the die to running temperature. 37

Product design 38

Pre-staged parts 39

Cleanability • Flush fasteners speed cleaning 40

Quick change tools • Power tools speed repetitive tasks • Vacuum or magnetic clamping 41

Vacuum or magnetic clamping 42

Parallel setup tasks • Ideally, two people can do the job in half the time as one person • Think about a pit stop at a car race 43

Improve external setups • Store fixtures, etc. , near machine • Prepare setup kits and carts • Improve material handling 44

Knowledge Check 45

What was the primary problem that led to the development of the quick changeover process? A) Persistent late deliveries by suppliers B) Moving material goods in and out of storage C) Workers standing around watching an automated machine D) Land costs in Japan were very high 46

Who is primarily responsible for creating quick changeover and SMED? A) Eiji Toyoda B) Shigeo Shingo C) Taiichi Ohno D) Edward Deming 47

Click on the definition and drag the correct answer to match the Process Type on the left. Process Type D Internal Processes B External Processes Definition A. Elements that can be performed when the machine is running. B. The time after processing during which the tooling, machinery is cleaned, identified, and tested for functionality prior to storage. C. The placement of the new tool, support equipment, and raw material before the next production lot. D. Elements in the changeover which can only be done when the machine is stopped. 48

Drag the Description to the matching SMED process step. Step Description B Step 1 A. Streamline all activities. E Step 2 B. Observe and record. D Step 3 C. Document internal and external procedures. A Step 4 C Step 5 D. Convert internal activities to external activities. E. Separate internal and external activities. 49

Describe one quick changeover method or tool. 50

Describe one potential application of quick changeover in your operation. 51