SMED
SMED (Single Minute Exchange of Die) , also known as Quick Changeover Time.
SMED originated in the early 1950s in Japan, Toyota enterprises developed by Shigeo Shingo Single mean less than 10 minutes (Minutes), originally used in automobile production plant to achieve rapid mold switch (Exchange of Dies), it help the Toyota enterprise switching time from 4 hours to 3 minutes.
SMED income: no additional inventory to meet customer requirements that the funds are not pressure on the additional inventory, shorten delivery time, reduce possible errors in the adjustment process, shorten the the parking time switch means higher production efficiency, ie OEE improved.
What SMED law?
SMED stands for "Sixty Seconds Instant retooling" (Single Minute Exchange of Die) is a fast and effective method for switching, quick die change law the concept that all changes (and start) can and should be less than 10 minutes ----- therefore only a single minute of this statement. So called single minute quick die change law retooling law, within 10 minutes, fast job changeover to constantly equipment installed quickly change to adjust this difficulty a changeover time - will likely shrink to a minimum (real-time-for-line ). It can be an ongoing production step to quickly switch to the next production step. Quick Die Change Act also often refers to the fast switching. Quick Die Change Act can and often is used to start a program and make it run fast, and at a minimum waste of the state.
SMED (Single Minutes Exchange of Die) in the early 1950s, Toyota Motor Corporation of Japan to explore a set of batches should be a small amount, reduce inventory, improve production system useful technique for rapid response capability. This approach was pioneered by Japan, Mr. Shigeo Shingo (Shigeo Shingo), and implemented in many enterprises argued. Single mean is less than 10 minutes (Minutes), Xinxiang witnessed Mr. hair changeover time is actually up to four hours, his response "must be allowed to flow smoothly together. Based on the Xinxiang Mr. experience, he developed a retooling process can be analyzed, so as to find the reason why the changeover time for field personnel, as well as how to reduce the corresponding method. Multiple cases which under his leadership, the changeover time or even be reduced to less than ten minutes, this rapid change type title units minute fast switching. Originally used in automobile production plant to achieve rapid mold switch (Exchange of Dies).
The name suggests, aims to reduce job changeover time, the key point is that delimit the internal job changeover and external job changeover, external and internal job changeover possible to become job changeover, then shorten as much as possible within the external job changeover time.
How should import the SMED law?
Our 5 step method to import of SMED, use the system to shorten the time of the changeover.
The first step: To observe the current process,
Step two: the distinction between internal and external elements
The third step: the internal job transfer to an external
Step 4: reduction of internal work,
Step 5: reduce external job.
The SMED method of three basic points
(1) to distinguish between "the transform operation," and "outer transform operation. The SMED Act requires that the equipment installed for the adjustment operation into the transform operation and outer transformation operation The former refers to those before the operation only after the machine has stopped; latter means that the device the operation performed in the operation process.
(2) reducing the "inner transformation operation. The SMED Act requirements as much as possible within the transformation operation outside transform into operation, which is the the SMED method of core. Transform operating downtime occupied, it is within the entire installed for the adjustment time should be shortened, the most critical is. The inner transformation operation is reduced to the minimum.
(3) to shorten the time of the transform operation ". As mentioned above, the transform operation "occupy the downtime., SMED method requires the use of the necessary technical means," transform operations time as short as possible. Simplify outer transformation operation, and must be run on the device process completed outside transform operation. "This may be a very short period of time after the shutdown of the equipment completed quickly change and adjustment of the equipment installed.
Typical switching basic process
30% preparation and clean-up
To prepare the parts and tools, and to check its condition
Removal of parts and tools, and to clean up
5% of the assembly and remove the parts
15% of the measurement setup and calibration
50% of the test run and adjustments
SMED steps
The first step: To observe the current process
Objective: changeover data should be collected
The same number of staff to ensure that the number of observers and tools placed
Observing the entire changeover process - from the last thing before the changeover until the changeover after the first product
Including time, record all the action
Find any problems or any chance
Necessary through video recording
Step two: the distinction between internal and external elements
Objective: To changeover time of the internal and external changeover time to separate, we can greatly reduce the changeover time
The first step in collecting the current data
Determine what things you can do before and after the shutdown
Use production tool replacement process records for each participating
The third step: the internal job transfer to external
Objective: internal job transfer to external changeover time can be further shortened
Strict inspection and analysis of internal activities
Examine first step to find the opportunity to
To discuss new approaches and creative brainstorming
Tools Standardization
Tools preheat
To ensure that the items are placed in the right position at the right time - tools, processes records table, raw materials, manpower, firmware, gaskets and ruler
Step 4: reduction of internal work
Objective: to achieve standardization of the changeover steps, the next step is to find and eliminate waste in the changeover process
The conventional method is to use the following means exclude waste changeover:
Parallel operation
Once rotary locking method
Touch clamp system
Placed Tools / location unified
Uniform size of the tool
Uniform size of the screw head
Details of the tool replacement table
Modified settings, avoid debugging
Step 5: reduce external job
Objective: To shorten the internal changeover time, you should also think of ways to reduce the workload of the machine during operation support staff
Improved external work constituted by the following means:
Placed next to the machine tools
Hand tools Desk located next to the machine
The ruler is placed next to the machine
Ready tool replacement ready checklist
Provide detailed tool replacement process record single
SMED project implementation
Select a representative switch operating
Team-building and ready SMED research
SMED study required inventory
Equipment checklist:
Video camera
Videotapes
Stopwatch
Whiteboard
Projector
VCR / TV
Materials checklist:
Film
Tape
Scissors
Notepad
Permanent Marker
Notices posts
Observe and record the current switching process
Do not stop in the middle, so that you can use the video analysis of each step time camera switching process,
Note that switching the hand, eye and body movement.
Review video content in a conference room and stopwatch records various activities
Observed switch - with a public notice affixed
Switching each step listed in the the pink public notice affixed
Record the time of each step in the public notice of the white paste
Recording the results observed in the yellow public notice paste
: Operator pick up the wrench
Went to the parts counter
Clamps the head is difficult to be positioned on the machine
Chart shows the current status of
Current situation with a brief description of the language
Words to describe the current situation, including the length of time to switch, who usually complete the job, and special events that occur in the process of switching. Including the number of tools, parts, etc..
The two operating personnel of the three kinds of switching process includes:
Replace the poppet framework, the feeding tube;
Select the new program;
Adjust the feed tube separator bottle boot device, sealing and coding.
Set improvement goals
Write the target, including the target value of the switching time and the need to improve the time period, this is just SMED team members on the switching time to reduce the prediction, but the final result is usually more superior prediction
According to the three stages of SMED, step-by-step establishment and implementation of the improvement program
The first step: the distinction between internal and external
Step 2: The internal operation into external operation
Third step: optimization of a switching operation of various aspects of
The results of the inspection of the obtained
A standardized switching operation and training of operating personnel
SMED advantage of
Flexible production
No additional inventory to meet customer requirements.
Fast delivery
Shorten delivery time that funds are not pressure in extra inventory.
Good quality
Reduce possible errors in the adjustment process
Efficient production
Shorten the switching the parking time means higher productivity, that OEE improve.
Scrapped it possible to achieve JIT, a significant reduction in the product
The SMED benefits has two main aspects:
Improve the flow capacity
Improve the frequency of changeover
What is SMED quick die change technology
SMED quick die change technology expert Mr. Shigeo Shingo Toyota 1000 Dayton presses (die) by the 4-hour changeover time, after six months of improvement to 1.5 hours in 1969 to improve by the Japanese scene change line ( mode) time, and then after three months of improvement, change the line (mode) the time advocated reduced to 3 minutes to complete the actual changeover (mold) Case technology development from 1950 that changeover (mold ) job of setting the preparatory work within the set (job) and set outside (outside the line of operations) divided thoughts start, after 19 years of the womb. At the time (Single Set-Up), which means "fast change (die) in 9 minutes / set the single digits (Single) minutes to complete the practice known as" setting preparatory work to improve Italy .
Two. SMED Quick Die Change purpose
(1 reducing changeover times
(2 to increase the number of die change
(3 more small quantities of raw capacity
(4 more Levelized production capacity
(5 shorten delivery time
(6 reduce resource fluctuations
(7 reduce inventory quantity
(8 increase inventory turns
(9 to reduce the storage space
(10 to reduce the management workload
(11. Businesses more competitive
Three. SMED Quick Die Change Glossary:
Retooling: Any replacement product, but must be the machine or production line to stop production in order to engage in the exchange operation are. Also known as the setting.
Changeover time: in die change action, leaving the machine or production line to stop the production time, the previous batch last qualified parts with the next batch of sequential interval between a qualified parts.
3 Die Change (inside job): refers to the state of the machine must stop production line to die change action. Also known as "within the job" or "internal ready.
Line foreign operations (foreign operations): the die change action machines in production operation can still be carried out, also known as the "outside job" or "external ready.
Four. SMED Quick Die Change realm:
Realm of one: No concept of Quick Changeover no quick die change concept
Realm: Single Minutes Exchange Die bits minutes retooling
Realm of three: Zero the Exchange Die zero mold change
The realm four: One Touch Exchange Die a touch retooling
Realm of five: One Cycle Exchange Die retooling a week
Realm of six: No Need Exchange Die without retooling
Five. SMED quick die change six steps:
The fast switching of the main focus is to reduce the switching pause time of the production line, such a pause shorter the better. The switching speed of consumption of artificial time can be reduced, the focus should not be considered, of course, if you switch the artificial time can be reduced, and that is good, however.
Must be based on the following steps of thinking in order to reduce the switching time, step by step, step by step to.
1. Calculate the entire production preparation time.
Internal and external job separation.
3 within operating outside job.
4. Shorten operating within the time
5. Improve operating outside time
6. Standardized new program production preparation.
VI, SMED retooling skills and rules
Quickly switch aforementioned ideological steps, the greatest difficulty encountered is how to shorten operating within the machine operating outside the operating time. Following a few tips and rules if we are done, will be able to achieve their goals.
Rule One: parallel operation
The so-called parallel operations refers to two or more persons jointly engaged in switching action. The parallel operation is most likely to immediately shorten operating within the time effect. Another individual engaged in switching action slowly, perhaps it takes to one hour to complete. If collaboration by two, and perhaps can be done in 40 minutes or 20 minutes. Then the entire switching time from 1 hour is reduced to between 20-40 minutes. And man-hours required in parallel operation may be increased, unchanged, decreased, the focus is not to be considered. Because, to shorten the switching time of the obtained effect is much larger than the artificial part of the cost, this point is the average person easier ignored. Engaged in parallel operation, co-ordination between the two actions must drill skilled, especially need to pay attention to safety, non-accidental injury because of negligence.
Rule two: Do not move your feet
Switching action is mainly dependent on the hands of actions completed and feet must be to reduce the chance of movement or walking. Must be used when switching to props, mold, cleaning, etc. must be placed in a dedicated trolley, and have collated sequentially, reducing the time looking. The mold or switching items in and out moving lines must be designed to be easily in and out of the way, the switching action sequence to rationalization and standardization.
Rule Three: Special props
The so-called tool is a general-purpose appliances; props appliances specially designed for specialized uses. Like a magician poker special design, a stationery store to buy playing cards in general, then the magician want to conjure up some wonderful magic will be more difficult. Utensils used by the magician known as props, rather than tools.
Switching action as much as possible to use props do not use tools. Because the props can improve the efficiency of the switch, and to shorten the switching time. In addition, the determination of the appliance should props, to replace the numerical determination of scale or meter reading, with a block gauge or riffles. The most important thing is to try to reduce the types of props, to reduce looking to take on the time of the Board.
Rule Four: removing screws
In the switching operation, the screws are most commonly seen in the method of the fixed mold is used. Using screws of course necessary, but detachably to the action of the screw usually took a lot of switching time. If you look closely, also found screws abuse is really too much. For example, had only four screws enough, but used six screwing too many laps, but also time-consuming. The screws really play tight function only last lap only. Therefore, to improve the best solution is to eliminate fixed using screws. Have a screw-mortal hatred to go and then quickly mentality. For example, fixture, cassette socket available latch lever, intermediary shaft cam lock positioning plate to replace the screws.
Rule Five: a turn that is scheduled
Limited to certain conditions, still must use bolts, screws, they should also try to make efforts to reduce the time to tighten and remove the screws. Can do to remove the bolts, screws and can reach the lock function for the improvement goals. The main method can be used only rotation once screwed tight or relaxed. For example, the C-shaped opening washers, pad in the nut, simply loosen the nut a lap later, the C-ring can be removed opening reach complete relaxation purposes. Tighten reverse line only revolution can achieve bolted. In addition, like a gourd-hole can also achieve this purpose.
The second method is to make the locking parts highly immobilized the excessive locking parts to be cut as low as the standard height; too low parts of the locking pad to reach the height of the standard can be added. The height of each mold-locking parts are standardized, then tightening of the nut parts does not change, so may reduce the rotation of the lock relaxation times, of course, also reduces the switching time.
Rule six: standardization
The switching action is different because the product of mold or working conditions must be replaced. Must also be adjusted for the movement, to set a new standard. Adjust the action usually takes about 50% -70% of the entire switching time, and adjust the length of time variation, good luck, once adjusted, bad luck, you need to spend tens of minutes or even a few The circumstances of the hour, can often see. Adjust the action, you must adjust is a waste, to exclude the adjustment action for improvement goals.
Adjusted to exclude waste, to master the method the live standard fixed rule, in other words, the machine has set a good standard, not to replace the mold, but to change. Approach to operating within the adjustment action moved to the outside of the job, and well in advance of the action set; Do not disassemble the entire mold retain mold base, only replace the cavity parent-constructed to eliminate mold set action ; or shared fixture can be used to do dual-switch operation, that is, a group of processing, another group prepared material has set, just rotate over switch can immediately reach switch purposes. Mold highly standardized, and adjust the operation of the stroke can also be saved. Another example is the injection molding machine must be based on a multi-use mold, adjust the settings several different stroke or conditions, the adjustment can be set as a model, sets up the hand wave to all at the same time set.
More importantly, to cancel the scale or meter reading values to work to identify the conditions, try to change to reduce the adjustment time to block the regulation, the limit set fast and so easy to pick and place, and then shorten the switching time.
Rule Seven: Preparation
Preparation operations are operating outside work. If outside the job is done well, it will affect the smooth operating within the switching time becomes longer. Example: operating outside did not fully prepared, including jobs, can not find the required props or mold error, such as poor, we must temporarily halt find props or trimming mold, caused by operating within the time becomes longer.
The outside job action should be improved so standardized. Setting change mode special vehicle will be required mold, props, the all die change schedule and related equipment on the trolley, to reduce individual looking and handling time. The mold placed places have to clear the storage areas marked with a meaningful number. Storage of equipment, instruments, props do not function to place special boxes placed, be a different product or mold making group sets of better. The establishment of a checklist to help indecent necessary equipment are complete, and fix the standard switching procedure table, and to distinguish between jobs, the grouping. In addition, the usual cleaning, cleaning, finishing, rectifying action must do, which contribute to operating outside prepared.
Retooling the skills and rules:
Quickly switch aforementioned ideological steps, the greatest difficulty encountered is how to shorten operating within the machine operating outside the operating time. Following a few tips and rules if we are done, will be able to achieve their goals.
Steps to create retooling operations recorded
a. retooling program;
b. confirmed that members of the group;
c. observe and record the die change program;
d calculation time and create a chart;
e. define the current state;
f. posted and the establishment of the status quo of the chart and the test machine die change action;
g. Setting improvement goals, and write the description of the target;
h. Notice the status quo and goals.
