Value-stream mapping is the simple process of directly observing the flows of information and materials as they now occur, summarizing them visually, and then envisioning a future state with much better performance.
" Value stream " may be a new phrase in your vocabulary. A value stream is all the actions ( both value added and non-value added ) currently required to bring a product through the main flows essential to every product: (1) the production flow from raw material into the arms of the customer, and (2) the design flow from concept to launch. This workbook looks at the production flow from customer demand back through raw material, which is the flow we usually relate to lean manufacturing and precisely the area where may have struggled to implement lean methods.
Value-stream mapping is a pencil and paper tool that helps you to see and understand the flow of material and information as a product makes its way through the value stream. What we mean by value-stream mapping is simple: Follow a product's production path from customer to supplier, and carefully draw a visual representation of every process in the material and information flow. Then ask a set of key questions and draw a " future-state " map of how value should flow.
Value stream mapping is a more recent technique designed specifically around the Toyota version of Lean Manufacturing. Figure 2 illustrates this technique.
Value stream mapping is performed in the following manner:
- Select a product family.
- Create a current-state map.
- Create a future-state map using lean techniques.
- Create an implementation plan for the future state.
- Implement the future state through structured continuous improvement activities.
( Daniel T. Jones,James P. Womack, Seeing the Whole: Mapping the Extended Value Stream, pg. 1 )
( Mike Rother,John Shook, Learning to See: Value Stream Mapping to Create Value and Eliminate Muda, pg. 3,4 )
( Quarterman Lee,Brad Snyder, Value Stream & Process Mapping: Genesis of Manufacturing Strategy, pg. 9,11 )
( Kevin J. Duggan, Creating Mixed Model Value Streams: Practical Lean Techniques for Building to Demand, pg. 7 )
Value Stream Mapping (time 9:17am 06.03.2011) ( Old )
Value stream mapping (VSM) aims to map the relations among entity, material, and information flow. There is the current VSM and the future VSM. In the future VSM you need to identify the result target. In this case, the future does not mean long-term, rather the future state should be what you would like to achieve in three months to a year
(Hwaiyu Geng, Manufacturing Engineering Handbook, McGrawHill, page 959 Unit 51.19)
Value stream mapping (VSM) aims to map the relations among entity, material, and information flow. There is the current VSM and the future VSM. In the future VSM you need to identify the result target. In this case, the future does not mean long-term, rather the future state should be what you would like to achieve in three months to a year
(Hwaiyu Geng, Manufacturing Engineering Handbook, McGrawHill, page 959 Unit 51.19)
2_) Key performance indicator(KPI) ( New ) ( Better ) ( Performance Measurement )
In general, key performance indicator is understood to mean the interpretation of a numerical value that is returned by a key performance indicator definition under specified framework conditions. Let us consider the example of a " Process runtime for purchasing processes in August 2004 " key performance indicator that has the value " 5 days ". The key performance indicator definition should be understood as a key performance indicator for the purposes of ARIS PPM, in this instance for example " process runtime ". Limiting the range to " Purchasing processes in August 2004 " serves as a filter for a " dimention ". A dimention is a process-relevant variable that is used for catagorizing processes. In the example described, the " point in time " ( = August 2004 ) and the " process type " ( = Purchasing process ) are dimentions.
A Key Performance Indicator ( KPI ) is the measure of performance of an activity that is critical to the success of an organization. Beyond the high level maxim that " You can't control what you don't measure ", the definition of those specific key indicators whose implementation and use would bring the most measurable benefit to a specific organization can vary substantially from organization to organization. KPI's must therefore be tailored to individual settings.
( August-Wilhelm Scheer,Wolfram Jost,Helge Heß,Andreas Kronz, Corporate Performance Management: Aris in Practice, pg. 50 )
( Albert Stähli, Management Andragogics 2: Zurich Living Case, pg. 212 )
Key performance indicator (KPI), is a number or value which can be compared against an internal target, or an external target ‘‘benchmarking’’ to give an indication of performance. That value can relate to data collected or calculated from any process or activity.
3_) Vacuum chuck ( New ) ( Machine Tools )
Vacuum chucks are being used for holding non-ferrous; non-magnetic parts for milling where holding without distortion is vital. A vacuum chuck is a section holding device relying on a vacuum pump to reduce the atmospheric pressure. The requirement for material to be held in vacuum are that sufficient area be provided for atmospheric pressure contact ( min 2 sq in ); that surface be flat and materials nonporous. A schematic of the vacuum chuck is shown in Fig. 8.45.
The vacuum chuck shown above is based on a unique value system. A pattern of tapped ports are filled out with individual valve screws, permit controlling the vacuum are by merely opening the valve directly below the part to be chucked. Unused valves are sealed by individual ' O ' rings.
Magnetic and Vacuum chucks can be more economical because in many cases the need for expensive mechanical, hydraulic or air clamping device is eliminated. This may result in reduction of size of machine table to hold a given number of parts and more parts per setup. Moreover smaller diameter cutters may be used since no clearance is required as with mechanical clamps.
( Dr. R. Kesavan, Machine Tools, pg. 8-45 )
THERE IS NOT OLDER DEFINITION !!!
4_) Crown gear ( New ) ( Gear Types )
A crown gear is a bevel gear where the pitch cone angle is 90 and bears the same relation to a bevel gear as a rack does to a spur gear. The tooth form in the bevel gear is slightly modified from a true involute. To ensure practical gear cutting, the basic crown gear have straight sided teeth. The cutting tools having straight cutting edges are inclined to give the desired pressure angle. Strictly speaking, the basic crown gear tooth should be slightly curved to attain the true involute form. Cutting should also conform accourdingly to produce this contour. To avoid practical difficulties associated with giving cutters a curved outline, straight teeth are used as indicated before. The teeth produced are said to have " octoid " form. In the generation method, a straight sided tool simulating the crown gear and the blank of the bevel gear cone roll on each other, producing the desired bevel gear.
The basic shape of a bevel gear tooth is almost the same as that of the spur gear. The tooth tapers off as it approaches the apex. The contour of the tooth also varies along its entire length. The angle between the shafts will depend on the conditions of drive. It is usually 90 degree, but can have other angles also.
The configurations of the straight-sided bevel gears have been shown in Fig. 5.1.
( Maitra, Handbook of Gear Design, pg. 5-1, 5-2 )
THERE IS NOT OLDER DEFINITION !!!
5_) Rubber-die forming ( New ) ( Manufacturing Methods )
The rubber-die forming process, known as the " Guerin Process " utilizes a flat, thick pad of rubber and a single male die of any material with sufficient toughness to stand up under the working pressures involved. Plastics, low melting point alloys, impregnated fiber, and wood can be used. For greatest life as well as for intricate parts, metal dies are required. Dies are low in cost, easy to produce and require no fitting. The rubber pad on the upper press platen mates with the die regardless of form, shape or size. Blanking as well as drawing is possible. In some cases parts can be blanked and formed in one operation. Stock up to 0,040-inch can normally be blanked by this method.
Ideal where quantities of a variety of machine parts are needed constantly, a great many different parts can be formed or drawn at the same time, Fig. 30.8.
At each loading of the platen, a full-sized sheet of metal can be cut or pressed into parts. In normal operation over 15,000 parts can be produced in 8 hours by this method, Fig. 30.9.
No lubricants are used and the parts emerge clean, eliminating a decreasing operation.
Rubber-die forming is successfully used for the drawing of aluminum and aluminum alloys, light-gage mild-steel sheet, stainless-steel sheet, copper and magnesium alloys. A minimum pressure of 1000 psi is required for working simple aluminum shapes. Greater pressures make for more perfect draws, especially with complicated parts. Hydraulic presses are considered best for this process and those in use range from 1000 to 5000 tons capacity.
( Roger William Bolz, Production Processes: The Productivity Handbook, pg. 30-06, 30-07 )
THERE IS NOT OLDER DEFINITION !!!
( Albert Stähli, Management Andragogics 2: Zurich Living Case, pg. 212 )
Key Performance Indicator
(KPI) ( Old )
Key performance indicator (KPI), is a number or value which can be compared against an internal target, or an external target ‘‘benchmarking’’ to give an indication of performance. That value can relate to data collected or calculated from any process or activity.
It was considered that the KPIs within the
manufacturing strategy are cost, quality, flexibility and delivery, as well as
inventory [3]. A part of a project survey was carried out to identify which
performance indicators
companies use and which ones they characterise
as important. The top five were: profitability, conformance to specifications,
customer satisfaction, return on investment and materials/overhead
cost.
(M.M. Ahmad, N. Dhafr, Robotics and
Computer Integrated Manufacturing, pp. 171-172)
3_) Vacuum chuck ( New ) ( Machine Tools )
Vacuum chucks are being used for holding non-ferrous; non-magnetic parts for milling where holding without distortion is vital. A vacuum chuck is a section holding device relying on a vacuum pump to reduce the atmospheric pressure. The requirement for material to be held in vacuum are that sufficient area be provided for atmospheric pressure contact ( min 2 sq in ); that surface be flat and materials nonporous. A schematic of the vacuum chuck is shown in Fig. 8.45.
The vacuum chuck shown above is based on a unique value system. A pattern of tapped ports are filled out with individual valve screws, permit controlling the vacuum are by merely opening the valve directly below the part to be chucked. Unused valves are sealed by individual ' O ' rings.
Magnetic and Vacuum chucks can be more economical because in many cases the need for expensive mechanical, hydraulic or air clamping device is eliminated. This may result in reduction of size of machine table to hold a given number of parts and more parts per setup. Moreover smaller diameter cutters may be used since no clearance is required as with mechanical clamps.
( Dr. R. Kesavan, Machine Tools, pg. 8-45 )
THERE IS NOT OLDER DEFINITION !!!
4_) Crown gear ( New ) ( Gear Types )
A crown gear is a bevel gear where the pitch cone angle is 90 and bears the same relation to a bevel gear as a rack does to a spur gear. The tooth form in the bevel gear is slightly modified from a true involute. To ensure practical gear cutting, the basic crown gear have straight sided teeth. The cutting tools having straight cutting edges are inclined to give the desired pressure angle. Strictly speaking, the basic crown gear tooth should be slightly curved to attain the true involute form. Cutting should also conform accourdingly to produce this contour. To avoid practical difficulties associated with giving cutters a curved outline, straight teeth are used as indicated before. The teeth produced are said to have " octoid " form. In the generation method, a straight sided tool simulating the crown gear and the blank of the bevel gear cone roll on each other, producing the desired bevel gear.
The basic shape of a bevel gear tooth is almost the same as that of the spur gear. The tooth tapers off as it approaches the apex. The contour of the tooth also varies along its entire length. The angle between the shafts will depend on the conditions of drive. It is usually 90 degree, but can have other angles also.
The configurations of the straight-sided bevel gears have been shown in Fig. 5.1.
( Maitra, Handbook of Gear Design, pg. 5-1, 5-2 )
THERE IS NOT OLDER DEFINITION !!!
5_) Rubber-die forming ( New ) ( Manufacturing Methods )
The rubber-die forming process, known as the " Guerin Process " utilizes a flat, thick pad of rubber and a single male die of any material with sufficient toughness to stand up under the working pressures involved. Plastics, low melting point alloys, impregnated fiber, and wood can be used. For greatest life as well as for intricate parts, metal dies are required. Dies are low in cost, easy to produce and require no fitting. The rubber pad on the upper press platen mates with the die regardless of form, shape or size. Blanking as well as drawing is possible. In some cases parts can be blanked and formed in one operation. Stock up to 0,040-inch can normally be blanked by this method.
Ideal where quantities of a variety of machine parts are needed constantly, a great many different parts can be formed or drawn at the same time, Fig. 30.8.
At each loading of the platen, a full-sized sheet of metal can be cut or pressed into parts. In normal operation over 15,000 parts can be produced in 8 hours by this method, Fig. 30.9.
No lubricants are used and the parts emerge clean, eliminating a decreasing operation.
Rubber-die forming is successfully used for the drawing of aluminum and aluminum alloys, light-gage mild-steel sheet, stainless-steel sheet, copper and magnesium alloys. A minimum pressure of 1000 psi is required for working simple aluminum shapes. Greater pressures make for more perfect draws, especially with complicated parts. Hydraulic presses are considered best for this process and those in use range from 1000 to 5000 tons capacity.
( Roger William Bolz, Production Processes: The Productivity Handbook, pg. 30-06, 30-07 )
THERE IS NOT OLDER DEFINITION !!!
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