Production Preparation Process (3P) December 7, 2007
Posted by Lawrence Loucka in : Definitions, Lean , add a comment
3P is about rapidly designing product and production processes to ensure capability, built-in quality, productivity, and Flow-Takt-Pull. The Production Preparation Process minimizes resources needed such as capital, tooling, space, inventory, and time. Rather than tweaking an existing shop floor process, we start with a clean sheet of paper. The 3P process is used to develop a product line specific production system in the shortest time to satisfy design and quality requirements, concept to market time goals,production requirements, and cost requirements.
3P simulates the actual components, product and production line of a new product during the early stages of the design process to learn about manufacturing or delivery requirements before making commitments to a floor plan or process flow. The goal is to produce a product that meets customer demand with perfect quality and at the desired cost. From beginning to end, 3P is an exercise in project management and waste elimination. 3P is a valuable tool because the cost of eliminating waste in the earliest stages of product development is less than during the final stages. The tool is useful and effective when you need to develop a method to meet customer requirements, plan production capacity for new or changing demand, transition new products, set a target date for delivering to market or prove the business-case target cost.
The 3P cross-functional team should include designers, engineers (i.e., manufacturing, quality and process), operators, operations experts and anyone else instrumental in bringing the product to market. Using lean principles, the cross-functional team creates a mock-up of the product and walks through how the product will flow through the factory. Mock-ups may be made from cardboard, plastic foam, wood or any other material that makes sense. Multiple 3P events are usually required throughout the design and development phases of a new product.
Here are the basic steps for 3P:
Moonlighting, Moonshining, Skunksworks, Trystorming and 3P November 19, 2007
Posted by Lawrence Loucka in : Definitions, Lean, Lean Sigma , 1 comment so far
Moonlighting - work a second job, usually after hours; "The med student is moonlighting as a taxi driver". To work at another job, often at night, in addition to one’s full-time job. Also to sell unused vacation time to do some consulting - how I got in to this line of work.
Moonshining - Illicit distilling. Often at night with home made apparatus. When several Japanese consultants from Shingijitsu were working with Boeing on kaizen they observed a team member bringing some homemade fixtures in to solve a problem. Described as "doing a little moonlighting" this term was misunderstood or mistranslated as moonshining, now the common term used to describe a key stage of 3P - Production Preparation Process.
Skunk Works - A skunkworks is a group of people who, in order to achieve unusual results, work on a project in a way that is outside the usual rules. A skunkworks is often a small team that assumes or is given responsibility for developing something in a short time with minimal management constraints. Typically, a skunkworks has a small number of members in order to reduce communications overhead. A skunkworks is sometimes used to spearhead a product design that thereafter will be developed according to the usual process. A skunkworks project may be secret. The name is taken from the moonshine factory in Al Capp’s cartoon, "Lil’ Abner."
The following are from Kelly Johnson of Lockheed’s Skunk Works:
- The Skunk Works manager must be delegated practically complete control of his program in all aspects. They should report to a division president or higher.
- Strong but small project offices must be provided both by the military and industry.
- The number of people having any connection with the project must be restricted in an almost vicious manner. Use a small number of good people (10% to 25% compared to the so-called normal systems).
- A very simple drawing and drawing release system with great flexibility for making changes must be provided.
- There must be a minimum number of reports required, but important work must be recorded thoroughly.
- There must be a monthly cost review covering not only what has been spent and committed but also projected costs to the conclusion of the program. Don’t have the books ninety days late and don’t surprise the customer with sudden overruns.
- The contractor must be delegated and must assume more than normal responsibility to get good vendor bids for subcontracts on the project. Commercial bid procedures are very often better than military ones.
- The inspection system as currently used by ADP, which has been approved by both the Air Force and Navy, meets the intent of existing military requirements and should be used on new projects. Push more basic inspection responsibility back to subcontractors and vendors. Don’t duplicate so much inspection.
- The contractor must be delegated the authority to test their final product in flight. They can and must test it in the initial stages. If they don’t, they rapidly lose their competency to design other vehicles.
- The specifications applying to the hardware and software must be agreed to in advance of contracting. A specification section stating clearly which important military specification items will not knowingly be complied with and reasons is highly recommended.
- Funding a program must be timely so that the contractor doesn’t have to keep running to the bank to support government projects.
- There must be mutual trust between the military project organization and the contractor with very close cooperation and liaison on a day-to-day basis. This cuts down misunderstanding and correspondence to an absolute minimum.
- Access by outsiders to the project and its personnel must be strictly controlled by appropriate security measures.
- Because only a few people will be used in engineering and most other areas, ways must be provided to reward good performance by pay not based on the number of personnel supervised.
"When the prototype approach for system development is used, ultimate production of the system must be considered throughout the design and evaluation phase."
See Wikipedia for more on Lockheed Skunk Works.
Trystorming - extends brainstorming by quickly creating mock-ups that can be rapidly and thoroughly evaluated. Trystorming refers to taking an idea and trying it out in practice. If the idea concerns the design of a product, you mock-up the product. If the idea is about a process improvement, you pilot the improvement. Sometimes we start with sketches, then table top ‘paper dolls’, then move on to life size mock ups with cardboard, 2 by 4’s, or whatever comes to hand. Finally build a functional model, although maybe not ‘industrial strength’ we prove out the concepts before building or buying the final machines, products, or processes.
Demand Segmentation November 8, 2007
Posted by Lawrence Loucka in : Definitions, Lean, Lean Sigma, Logistics, Supply Chain , 1 comment so far
Traditional Product Quantity (PQ) or ABC analysis fails to recognize that high volume may not be predictable and that low volume can be. So when trying to determine which products may lend themselves readily to pull techniques we can run into trouble if we don’t understand demand variation. Get some demand data - build a spreadsheet or table listing products in rows and demand in columns, calculate average demand, Cv (the standard deviation divided by demand average), and plot it as here. Here are some considerations:
- Altitude - this analysis typically starts with customer demand but can be done by market, customer, finished goods, in-process, raw materials, suppliers i.e. anywhere along the supply chain where there is consumption.
- Time Bucket - depending on the ‘clock speed’ of the enterprise the demand data can be aggregated by month, week, day, or hour. When gathering data start with the smallest time period possible. It’s easy to convert daily demand to week or month but impossible to take monthly and say anything about daily demand.
- Unit of Measure - the units of volume may be straight forward, for example ‘pieces’ or may be complicated due to different value streams or product lines having a mix of units. You may need to convert your data to a common unit. Dollars can be a common unit.
- Demand - sometimes not easy to get. Shipments may not represent true customer demand, especially if on-time delivery and order fill aren’t very high. Getting original customer demand can be difficult if the customer order entry system forces ship complete or when back orders lose original request dates (and quantities).
- Geography - like altitude, this analysis can be done by production cell, value stream, plant or DC, business unit, or enterprise.
- Horizon - use forecast to determine volume, especially if product life cycles are short. Using history to predict future volume is like driving by looking in the rear view mirror - it can be done, but reaction time is a little slow, and its hard to see the ‘cliff event’ until it’s too late. Sometime forecast is crap or isn’t available, so then use very recent history.
- Timeline - usually want at least 25 data points to calculate a meaningful standard deviation of the demand history.
- Scrub - other than filtering out abnormal orders consider weekend transactions, huge one-time orders, and zeros. Excel and Access treat blanks and zeros differently. As you take the transaction log and build a pivot table of part number vs. date you’ll have cells with no data because no transactions occur on that day for that item. Use search/replace to replace blank with zero. But for new products coming to life during the study period you might leave cells blank prior to the launch date. Similarly if a product has regular demand, say Monday, Wednesday, Friday you might want to leave Tuesday and Thursday blank.
- Plot - volume vs. Cv
- Interpret - Cv’s less than 1.0 lend themselves to flow and pull techniques. Cv’s less than 0.5 can often be handled with rate-based replenishment methods. Remember a Cv of 1.0 means the demand variation is a great as the demand average. Say a part has an average daily demand of 100 with a Cv of 1.0 the demand one day could be zero and the next 200 or more - not very predictable. High Cv items are usually low volume, but not always. Take a look at the three data points in the top center of the graph above. Must be a story here - why are the highest volume parts so unpredictable?
Product Family Turnover Rate, Every Product Every October 27, 2007
Posted by Lawrence Loucka in : Definitions, Lean , 1 comment so far
In mixed model fixed repeating scheduling we want to balance run time and changeover time, that is we want to determine how much to run and the time interval between successive runs. Some refer to this a Every Product Every Interval (EPEI). Here’s the math:
A = Available Time (*% Uptime)
L = Production Load = sum run time for all members of the product family ( average demand for product i * cycle time for product i). Note that this doesn’t include changeover time.
C = Total Changeover Time = sum of changeover times needed to accomplish one changeover for each product in the family
PFTR = (A - L) / C
Example:
Available time is 2 shifts of 8 hours and 10% unplanned downtime
We have 4 products in the family with average daily demand of 14 A’s, 6 B’s, 4 C’s and 2 D
Cycle time for a unit is the same for all products, and is 30 minutes per piece
Changeover time between each product is 60 minutes
So:
A = 2 shifts/ day * 8 hrs/shift * 0.90 = 960 minutes * 0.90 = 864 minutes/day of effective available time
L = (14 + 6 + 4 + 2) * 30 minutes per piece = 780 minutes/day of production load or run time
C = 4 products * 1 hour changeover = 4 hours = 240 minutes/family
PFTR then is (864 - 780) / 240 = 0.35 or a EPE Interval of 2.85 days.
Our run sizes would be 40 A’s, 17 B’s, 12 C’s and 6 D’s.
Here’s another example:
Number of different parts running through an injection molding center = 20
Setups take 1 hour between each mold change
20 days in a month, 16 hours in a day
Available Time = 20 day/month * 16 hours /day = 320 hr/month
Load or run time = sum or all cycle times to produce a month of demand = 280 hrs/ month
Time available to do change overs = 320-280 = 40 hours a month
Number of cycles per month = 40/20 = 20
Repeat Interval = 10 days, so make 10 days worth of each part every 10 days.
Muda in the Warehouse September 25, 2007
Posted by Lawrence Loucka in : Consulting, Definitions, Lean, Lean Sigma, Logistics, Supply Chain , add a comment
Although created in the manufacturing environment of Toyota by Taiichi Ohno, the Seven Wastes can be found almost everywhere, if you learn how to see them. Here’s some lean thinking for the warehouse:
Overproduction - Think about the consequences when consumers, retailers, wholesalers, distributors, and manufacturers justify "just in case" or Murphy stock as a hedge against unplanned demand. Money, time, people, physical assets, the environment have all been tied up for something that isn’t needed.
Waiting - the ‘hurry up and wait’ of trucks sitting idle or drivers killing time awaiting their turn at the dock, or DC workers or lifts standing by waiting for tools, instructions, materials to arrive or to be taken away. Waiting comes from poor layout, lumpy demand, system batching. Then once the blockage is cleared we hustle.
Defective Product or Service - from picking errors, incorrect order quantities, misplaced stock to shipping on the wrong carrier or the wrong mode these errors consume resources of time, people and materials to no useful end. Worse yet, additional resources, often 2 or 3 times the original, are usually needed to correct the error.
Overprocessing - how about dock audits, redundant approvals, pick/pack/ship audits, cycle counting? Another example of overprocessing the the warehouse is the failure to rationalize the supply base and concentrate relationship management on a few top-tier suppliers. What about rationalizing the carriers? Both result in inefficient duplication of resources, decisions, and communications.
Moving Product - like overproduction, the unnecessary movement of product can occure both within the warehouse and throughout the entire supply chain. Too many steps, too many stops, unnecessary movement from suppliers though master DC’s to regional DC’s for further deployment to customers can be deadly drivers of cost and time, labor, and space.
Moving People - in the warehouse an enormous percentage of people’s time is devoted to movement, such as picking, put-away, and replenishment. If a facility isn’t well laidout with easy access to "A" items an enormous amount of time can be wasted in traveling empty. When good aren’t where they’re supposed to be the movement to the wrong location is both a defect and a waste of human motion.
Ineffective Inventory Control - creates waste a several levels. Excess inventory based on bad inventory data diverts limited capital into creation and maintenance of waste. Excess inventory results in consuming valuable storage space to hold unnecessary goods. A scarcity of items, on the other hand, results in stock outs, expediting, or lost orders.