{"id":56,"date":"2019-07-08T15:15:01","date_gmt":"2019-07-08T15:15:01","guid":{"rendered":"https:\/\/libraryresources.nse.org.ng\/industrialengineeringintro\/chapter\/lean-operations\/"},"modified":"2026-03-16T14:21:27","modified_gmt":"2026-03-16T14:21:27","slug":"lean-operations","status":"publish","type":"chapter","link":"https:\/\/libraryresources.nse.org.ng\/industrialengineeringintro\/chapter\/lean-operations\/","title":{"raw":"Lean Operations","rendered":"Lean Operations"},"content":{"raw":"<h1>Chapter Table of Contents<\/h1>\n<ul>\n \t<li><a href=\"https:\/\/libraryresources.nse.org.ng\/industrialengineeringintro\/chapter\/lean-operations\/#Wastes\">Wastes<\/a><\/li>\n \t<li><a href=\"https:\/\/libraryresources.nse.org.ng\/industrialengineeringintro\/chapter\/lean-operations\/#Value\">Value<\/a><\/li>\n \t<li><a href=\"https:\/\/libraryresources.nse.org.ng\/industrialengineeringintro\/chapter\/lean-operations\/#Flow\">Continuous Flow<\/a><\/li>\n \t<li><a href=\"https:\/\/libraryresources.nse.org.ng\/industrialengineeringintro\/chapter\/lean-operations\/#Pull\">Pull and Continuous Improvement<\/a><\/li>\n \t<li><a href=\"https:\/\/libraryresources.nse.org.ng\/industrialengineeringintro\/chapter\/lean-operations\/#Exercise\">Exercise<\/a><\/li>\n<\/ul>\n[caption id=\"attachment_54\" align=\"aligncenter\" width=\"513\"]<img class=\"wp-image-54 size-full\" src=\"https:\/\/libraryresources.nse.org.ng\/wp-content\/uploads\/sites\/17\/2019\/07\/Lean1.jpg\" alt=\"\" width=\"513\" height=\"512\"> Figure 9.1: Lean Operations Word Map[\/caption]\n<h1><span style=\"font-family: Lato, Helvetica, sans-serif; font-size: 1em; letter-spacing: 1px; text-transform: uppercase;\">Wastes<\/span><\/h1>\n<div class=\"pages_block\">\n<div data-click-id=\"648fb497-ee3f-4991-8538-d58bffcdd518\">\n<div class=\"HTMLContentstyles__Wrapper-hv2w60-0 fgnwfi\">\n<p id=\"648fb497-ee3f-4991-8538-d58bffcdd518\" style=\"text-align: justify;\">The word \u201clean\u201d means skinny or having no fat. Lean operations have no waste. The types of wastes, also called <b><i>muda<\/i><\/b>, that lean operations can be referred to as TIM WOODS:<\/p>\n\n<\/div>\n<\/div>\n<\/div>\n<div class=\"pages_block\">\n<div data-click-id=\"b005451e-ed97-4c4f-8a5e-cc063d5cacbe\">\n<div class=\"HTMLContentstyles__Wrapper-hv2w60-0 fgnwfi\">\n<ul id=\"b005451e-ed97-4c4f-8a5e-cc063d5cacbe\">\n \t<li><span style=\"color: #ab533d;\">T<\/span> \u2013 Transport \u2013 Moving people, products &amp; information<\/li>\n \t<li><span style=\"color: #ab533d;\">I<\/span> \u2013 Inventory \u2013 Storing parts, pieces, documentation ahead of requirements<\/li>\n \t<li><span style=\"color: #ab533d;\">M<\/span> \u2013 Motion \u2013 Bending, turning, reaching, lifting<\/li>\n \t<li><span style=\"color: #ab533d;\">W<\/span> \u2013 Waiting \u2013 For parts, information, instructions, equipment<\/li>\n \t<li><span style=\"color: #ab533d;\">O<\/span> \u2013 Over production \u2013 Making more than is IMMEDIATELY required<\/li>\n \t<li><span style=\"color: #ab533d;\">O<\/span> \u2013 Over processing \u2013 Tighter tolerances or higher grade materials than are necessary<\/li>\n \t<li><span style=\"color: #ab533d;\">D<\/span> \u2013 Defects \u2013 Rework, scrap, incorrect documentation<\/li>\n \t<li><span style=\"color: #ab533d;\">S<\/span> \u2013 Skills \u2013 Under utilizing capabilities, delegating tasks with inadequate training<\/li>\n<\/ul>\n<\/div>\n<\/div>\n<\/div>\n<div class=\"pages_block\">\n<div data-click-id=\"4505b6df-1524-4bb9-9626-50a7c0d5c441\">\n<div class=\"HTMLContentstyles__Wrapper-hv2w60-0 fgnwfi\">\n<p id=\"4505b6df-1524-4bb9-9626-50a7c0d5c441\" style=\"text-align: justify;\">The framework of lean operations focuses on the concepts of value, value stream, flow, pull, and perfection in order to reduce all of these types of waste.<\/p>\n\n<\/div>\n<\/div>\n<\/div>\n<div class=\"pages_block pages_heading--react\">\n<div data-click-id=\"24e99486-44ed-466f-9e92-80e236a1bcf0\">\n<div class=\"HTMLContentstyles__Wrapper-hv2w60-0 fgnwfi\">\n<h1 id=\"24e99486-44ed-466f-9e92-80e236a1bcf0\"><a id=\"Value\" href=\"\"><\/a>Value<\/h1>\n<\/div>\n<\/div>\n<\/div>\n<div class=\"pages_block\">\n<div data-click-id=\"9217fdc7-54f2-42ef-aaf1-6070ed5efbc1\">\n<div class=\"HTMLContentstyles__Wrapper-hv2w60-0 fgnwfi\">\n<p id=\"9217fdc7-54f2-42ef-aaf1-6070ed5efbc1\" style=\"text-align: justify;\"><b>Value<\/b> is defined by the customer. An organization must have a clear definition of value as perceived by the customer. Time and money spent on features of a product or a service that the customer does not perceive have value are wasted time and money. Knowing what the customer values requires becoming close to the customer and constantly soliciting feedback.<\/p>\n<span style=\"text-align: justify;\">In lean operations, a process flow diagram is called a <\/span><b style=\"text-align: justify;\">value stream map<\/b><span style=\"text-align: justify;\">. The diagram is similar, but the reason for creating the diagram is to identify all the activities in a process and place them into one of the following categories.<\/span>\n\n<\/div>\n<\/div>\n<\/div>\n<div class=\"pages_block\">\n<div data-click-id=\"d84b6d61-51de-4468-b9e2-8939a47b7908\">\n<div class=\"HTMLContentstyles__Wrapper-hv2w60-0 fgnwfi\">\n<ul id=\"d84b6d61-51de-4468-b9e2-8939a47b7908\">\n \t<li><b>Value Added\u00a0 (VA)<\/b> - activities that create value as perceived by the customer<\/li>\n \t<li><b>Non-Value Added <\/b><b>(NVA)<\/b>- activities which don\u2019t create value as perceived by the customer and so should be eliminated immediately<\/li>\n \t<li><b>Essential Non-Value Added\u00a0 (ENVA)<\/b> - activities that create no value but are company or regulatory policies and so can\u2019t be eliminated just yet<\/li>\n<\/ul>\n<\/div>\n<\/div>\n<\/div>\n<div class=\"pages_block\">\n<div data-click-id=\"d7e85393-de49-4ab6-8958-f0e9e7d3c5a5\">\n<div class=\"HTMLContentstyles__Wrapper-hv2w60-0 fgnwfi\">\n<p id=\"d7e85393-de49-4ab6-8958-f0e9e7d3c5a5\" style=\"text-align: justify;\">The value stream mapping also identifies the time actually spent in adding value and the time the product spends in storage or transport. Time in storage or transport is waste and should be eliminated.<\/p>\n&nbsp;\n\n[caption id=\"attachment_55\" align=\"aligncenter\" width=\"988\"]<img class=\"wp-image-55 size-full\" src=\"https:\/\/libraryresources.nse.org.ng\/wp-content\/uploads\/sites\/17\/2026\/03\/ValueStreamMapParts.png\" alt=\"Diagram shows the different parts of a Value Stream Map of material and information flow. The Information flows from customer to production control to supplier. The supplier then flows into material flow throuh the processes until the product is shipped to the customer. The Value Stream Map shows metrics of each step in the process including Cycle Time, Uptime, and Lead Time.\" width=\"988\" height=\"641\"> Figure 9.2: Value Stream Map[\/caption]\n<h1><a id=\"Flow\" href=\"\"><\/a>Continuous flow<\/h1>\n<div class=\"pages_block\">\n<div data-click-id=\"92972bc3-b642-4289-bcdb-9365df58c8ad\">\n<div class=\"HTMLContentstyles__Wrapper-hv2w60-0 fgnwfi\">\n<p id=\"92972bc3-b642-4289-bcdb-9365df58c8ad\" style=\"text-align: justify;\"><a class=\"medium-editor-link-added\" href=\"http:\/\/www.mmsonline.com\/articles\/picture-perfect-manufacturing\" rel=\"noopener noreferrer\">Picture-Perfect Manufacturing<\/a>, from MMS Online, describes how Stremel Manufacturing, in Minneapolis, Minnesota, used current state maps and future state maps to make sure that waste-reduction initiatives \u201cimprove the overall flow rather than merely optimize individual steps.\u201d<\/p>\n<span style=\"text-align: justify;\">In continuous <\/span><b style=\"text-align: justify;\">flow,<\/b><span style=\"text-align: justify;\">\u00a0a product never waits but flows continuously through the manufacturing system, thus eliminating time in storage and in transport. Batches and queues should be eliminated. If products move through the production systems in batches, then the first item in a batch must wait until the last item in a batch is completed before it moves to the next processing time; batches mean product spends time waiting, and that time is waste. The presence of queues mean that a product was completed at a previous processing step before the next step was ready for more input. Since the final step of the production process is shipping the product to customers, product should be produced at the rate that meets the market demand. The principle can be applied in the production of services also.<\/span>\n\n<span style=\"text-align: justify;\">One barrier to flow and one reason for using batches is the time necessary to switch the production facility from producing one kind of product to producing another, which is referred to as <strong>setup<\/strong><\/span><span style=\"text-align: justify;\">.\u00a0 <\/span><a style=\"text-align: justify;\" href=\"http:\/\/www.mmsonline.com\/articles\/setup-reduction-at-the-heart-of-lean-manufacturing\">Setup Reduction: At the Heart of Lean Manufacturing<\/a><span style=\"text-align: justify;\">, also from MMS Online, describes how Richards Industries, a manufacturer of specialty valves in Cincinnati, Ohio, reduced its setup times from an average of 50 minutes to 27 minutes. This reduction enabled them to reduce the typical batch size from 200 to about 20 to 30.<\/span>\n<p style=\"text-align: justify;\"><span style=\"text-align: justify;\">Flow can be improved by eliminating bottlenecks as shown by the following example from World War II as described by in Methods of Operations Research [footnote]Morse, P., &amp; Kimball, G. (1951). Methods of operations research (1st ed., rev.). Cambridge: Published jointly by the Technology Press of Massachusetts Institute of Technology, and Wiley, New York.[\/footnote].<\/span><\/p>\n\n<\/div>\n<\/div>\n<\/div>\n<div class=\"pages_block\">\n<div data-click-id=\"b007321d-9bbc-4119-a1c9-1cc7ed273e39\">\n<div class=\"HTMLContentstyles__Wrapper-hv2w60-0 fgnwfi\">\n<blockquote id=\"b007321d-9bbc-4119-a1c9-1cc7ed273e39\">\n<p style=\"text-align: justify;\">An operations research worker during his first day of assignment to a new field command noticed that there was considerable delay caused by the soldiers having to wait in line to wash and rinse their mess kits after eating. There were four tubs, two for washing and two for rinsing. The operations research worker noticed that on the average it took three times as long for the soldier to wash his kit as it did for him to rinse it. He suggested that, instead of there being two tubs for washing and two for rinsing, there should be three tubs for washing and one for rinsing. This change was made, and the line of waiting soldiers did not merely diminish in size; on most days no waiting line ever formed.<\/p>\n<\/blockquote>\n<\/div>\n<\/div>\n<\/div>\n<div class=\"pages_block\">\n<div data-click-id=\"7ea04d3f-633e-4f28-ab2a-376c4e7946a7\">\n<div class=\"HTMLContentstyles__Wrapper-hv2w60-0 fgnwfi\">\n<p id=\"7ea04d3f-633e-4f28-ab2a-376c4e7946a7\" style=\"text-align: justify;\">A <b>bottleneck<\/b> is the narrowest part of a bottle and limits the flow in or out of the bottle. In the original situation with only two tubs for washing, the lines in front of those tubs would have been long, indicating that the wash tubs were the bottleneck, that is, the place in the production process with the least capacity. If washing took three minutes and rinsing took one minute, two wash tubs can serve 40 soldiers per hour while two rinse tubs can serve 120 soldiers per hour. With the new configuration, three wash tubs can serve 60 soldiers per hour, the same service rate as one rinse tub.<\/p>\n<span style=\"text-align: justify;\">Bottlenecks can be identified by looking for places where <\/span><b style=\"text-align: justify;\">WIP (Work in Progress)<\/b><span style=\"text-align: justify;\"> piles up and create queues. The processing rate at a bottleneck can be increased by reducing the time to process one item or by adding more processing capability. As a bottleneck\u2019s rate is improved, WIP in front of the bottleneck will disappear, but another bottleneck may now appear.<\/span>\n\n<\/div>\n<\/div>\n<\/div>\n<div class=\"pages_block\">\n<div data-click-id=\"9ad0e705-e5f3-405a-a8be-02888e084854\">\n<div class=\"HTMLContentstyles__Wrapper-hv2w60-0 fgnwfi\">\n<h1><a id=\"Pull\" href=\"\"><\/a>Pull and Continuous Improvement<\/h1>\n<div class=\"pages_block\">\n<div data-click-id=\"7930d0b8-861d-45fe-a00f-15243799ef1c\">\n<div class=\"HTMLContentstyles__Wrapper-hv2w60-0 fgnwfi\">\n<p id=\"7930d0b8-861d-45fe-a00f-15243799ef1c\" style=\"text-align: justify;\">In a lean system, no product or service is produced until a customer asks for it, that is, product is pulled not pushed through the system. Some product must be maintained in sales places to meet immediate demand, but reduction in lead time through improvements such as daily deliveries reduces the amount of stock kept on hand and allows more variety in stock.<\/p>\n<p style=\"text-align: justify;\"><span style=\"text-align: justify;\">Lean systems constantly seek perfection by working to continuously improve. An organization should not compete against its competitors. If benchmarking shows the company is doing better than its competitors, it should not relax.\u00a0 As Womack and Jones state in their\u00a0 preeminent\u00a0 book on lean operations, <\/span><i style=\"text-align: justify;\">Lean Thinking<\/i><span style=\"text-align: justify;\"> [footnote]Jones, D. T., &amp; Womack, J. P. (2014). Lean thinking: Banish waste and create wealth in your corporation. Place of publication not identified: Free Press. [\/footnote], state:<\/span><\/p>\n\n<\/div>\n<\/div>\n<\/div>\n<div class=\"pages_block\">\n<div data-click-id=\"b065128c-98e7-418a-8fec-7b1f5f70ef7c\">\n<div class=\"HTMLContentstyles__Wrapper-hv2w60-0 fgnwfi\">\n<blockquote id=\"b065128c-98e7-418a-8fec-7b1f5f70ef7c\">To hell with your competitors; compete against perfection by identifying all activities that are muda and eliminating them.<\/blockquote>\n<\/div>\n<\/div>\n<\/div>\n<div class=\"pages_block\">\n<div data-click-id=\"03537f82-d09b-48d4-b4c4-a1699078e2be\">\n<div class=\"HTMLContentstyles__Wrapper-hv2w60-0 fgnwfi\">\n<p id=\"03537f82-d09b-48d4-b4c4-a1699078e2be\" style=\"text-align: justify;\">In addition to the tools listed above, industrial engineers use a lot of other tools to continuously try to reduce wastes in a production or service system.\u00a0 You will learn about these tools throughout your industrial engineering curriculum.<\/p>\n\n<h1><a id=\"Exercise\" href=\"\"><\/a>Exercise<\/h1>\n<code>The original version of this chapter contained H5P content. You may want to remove or replace this element.<\/code>\n\n<\/div>\n<\/div>\n<\/div>\n<\/div>\n<\/div>\n<\/div>\n<\/div>\n<\/div>\n<\/div>","rendered":"<h1>Chapter Table of Contents<\/h1>\n<ul>\n<li><a href=\"https:\/\/libraryresources.nse.org.ng\/industrialengineeringintro\/chapter\/lean-operations\/#Wastes\">Wastes<\/a><\/li>\n<li><a href=\"https:\/\/libraryresources.nse.org.ng\/industrialengineeringintro\/chapter\/lean-operations\/#Value\">Value<\/a><\/li>\n<li><a href=\"https:\/\/libraryresources.nse.org.ng\/industrialengineeringintro\/chapter\/lean-operations\/#Flow\">Continuous Flow<\/a><\/li>\n<li><a href=\"https:\/\/libraryresources.nse.org.ng\/industrialengineeringintro\/chapter\/lean-operations\/#Pull\">Pull and Continuous Improvement<\/a><\/li>\n<li><a href=\"https:\/\/libraryresources.nse.org.ng\/industrialengineeringintro\/chapter\/lean-operations\/#Exercise\">Exercise<\/a><\/li>\n<\/ul>\n<figure id=\"attachment_54\" aria-describedby=\"caption-attachment-54\" style=\"width: 513px\" class=\"wp-caption aligncenter\"><img decoding=\"async\" class=\"wp-image-54 size-full\" src=\"https:\/\/libraryresources.nse.org.ng\/wp-content\/uploads\/sites\/17\/2019\/07\/Lean1.jpg\" alt=\"\" width=\"513\" height=\"512\" srcset=\"https:\/\/libraryresources.nse.org.ng\/industrialengineeringintro\/wp-content\/uploads\/sites\/17\/2019\/07\/Lean1.jpg 513w, https:\/\/libraryresources.nse.org.ng\/industrialengineeringintro\/wp-content\/uploads\/sites\/17\/2019\/07\/Lean1-300x300.jpg 300w, https:\/\/libraryresources.nse.org.ng\/industrialengineeringintro\/wp-content\/uploads\/sites\/17\/2019\/07\/Lean1-150x150.jpg 150w, https:\/\/libraryresources.nse.org.ng\/industrialengineeringintro\/wp-content\/uploads\/sites\/17\/2019\/07\/Lean1-65x65.jpg 65w, https:\/\/libraryresources.nse.org.ng\/industrialengineeringintro\/wp-content\/uploads\/sites\/17\/2019\/07\/Lean1-225x225.jpg 225w, https:\/\/libraryresources.nse.org.ng\/industrialengineeringintro\/wp-content\/uploads\/sites\/17\/2019\/07\/Lean1-350x349.jpg 350w\" sizes=\"(max-width: 513px) 100vw, 513px\" \/><figcaption id=\"caption-attachment-54\" class=\"wp-caption-text\">Figure 9.1: Lean Operations Word Map<\/figcaption><\/figure>\n<h1><span style=\"font-family: Lato, Helvetica, sans-serif; font-size: 1em; letter-spacing: 1px; text-transform: uppercase;\">Wastes<\/span><\/h1>\n<div class=\"pages_block\">\n<div data-click-id=\"648fb497-ee3f-4991-8538-d58bffcdd518\">\n<div class=\"HTMLContentstyles__Wrapper-hv2w60-0 fgnwfi\">\n<p id=\"648fb497-ee3f-4991-8538-d58bffcdd518\" style=\"text-align: justify;\">The word \u201clean\u201d means skinny or having no fat. Lean operations have no waste. The types of wastes, also called <b><i>muda<\/i><\/b>, that lean operations can be referred to as TIM WOODS:<\/p>\n<\/div>\n<\/div>\n<\/div>\n<div class=\"pages_block\">\n<div data-click-id=\"b005451e-ed97-4c4f-8a5e-cc063d5cacbe\">\n<div class=\"HTMLContentstyles__Wrapper-hv2w60-0 fgnwfi\">\n<ul id=\"b005451e-ed97-4c4f-8a5e-cc063d5cacbe\">\n<li><span style=\"color: #ab533d;\">T<\/span> \u2013 Transport \u2013 Moving people, products &amp; information<\/li>\n<li><span style=\"color: #ab533d;\">I<\/span> \u2013 Inventory \u2013 Storing parts, pieces, documentation ahead of requirements<\/li>\n<li><span style=\"color: #ab533d;\">M<\/span> \u2013 Motion \u2013 Bending, turning, reaching, lifting<\/li>\n<li><span style=\"color: #ab533d;\">W<\/span> \u2013 Waiting \u2013 For parts, information, instructions, equipment<\/li>\n<li><span style=\"color: #ab533d;\">O<\/span> \u2013 Over production \u2013 Making more than is IMMEDIATELY required<\/li>\n<li><span style=\"color: #ab533d;\">O<\/span> \u2013 Over processing \u2013 Tighter tolerances or higher grade materials than are necessary<\/li>\n<li><span style=\"color: #ab533d;\">D<\/span> \u2013 Defects \u2013 Rework, scrap, incorrect documentation<\/li>\n<li><span style=\"color: #ab533d;\">S<\/span> \u2013 Skills \u2013 Under utilizing capabilities, delegating tasks with inadequate training<\/li>\n<\/ul>\n<\/div>\n<\/div>\n<\/div>\n<div class=\"pages_block\">\n<div data-click-id=\"4505b6df-1524-4bb9-9626-50a7c0d5c441\">\n<div class=\"HTMLContentstyles__Wrapper-hv2w60-0 fgnwfi\">\n<p id=\"4505b6df-1524-4bb9-9626-50a7c0d5c441\" style=\"text-align: justify;\">The framework of lean operations focuses on the concepts of value, value stream, flow, pull, and perfection in order to reduce all of these types of waste.<\/p>\n<\/div>\n<\/div>\n<\/div>\n<div class=\"pages_block pages_heading--react\">\n<div data-click-id=\"24e99486-44ed-466f-9e92-80e236a1bcf0\">\n<div class=\"HTMLContentstyles__Wrapper-hv2w60-0 fgnwfi\">\n<h1 id=\"24e99486-44ed-466f-9e92-80e236a1bcf0\"><a id=\"Value\" href=\"\"><\/a>Value<\/h1>\n<\/div>\n<\/div>\n<\/div>\n<div class=\"pages_block\">\n<div data-click-id=\"9217fdc7-54f2-42ef-aaf1-6070ed5efbc1\">\n<div class=\"HTMLContentstyles__Wrapper-hv2w60-0 fgnwfi\">\n<p id=\"9217fdc7-54f2-42ef-aaf1-6070ed5efbc1\" style=\"text-align: justify;\"><b>Value<\/b> is defined by the customer. An organization must have a clear definition of value as perceived by the customer. Time and money spent on features of a product or a service that the customer does not perceive have value are wasted time and money. Knowing what the customer values requires becoming close to the customer and constantly soliciting feedback.<\/p>\n<p><span style=\"text-align: justify;\">In lean operations, a process flow diagram is called a <\/span><b style=\"text-align: justify;\">value stream map<\/b><span style=\"text-align: justify;\">. The diagram is similar, but the reason for creating the diagram is to identify all the activities in a process and place them into one of the following categories.<\/span><\/p>\n<\/div>\n<\/div>\n<\/div>\n<div class=\"pages_block\">\n<div data-click-id=\"d84b6d61-51de-4468-b9e2-8939a47b7908\">\n<div class=\"HTMLContentstyles__Wrapper-hv2w60-0 fgnwfi\">\n<ul id=\"d84b6d61-51de-4468-b9e2-8939a47b7908\">\n<li><b>Value Added\u00a0 (VA)<\/b> &#8211; activities that create value as perceived by the customer<\/li>\n<li><b>Non-Value Added <\/b><b>(NVA)<\/b>&#8211; activities which don\u2019t create value as perceived by the customer and so should be eliminated immediately<\/li>\n<li><b>Essential Non-Value Added\u00a0 (ENVA)<\/b> &#8211; activities that create no value but are company or regulatory policies and so can\u2019t be eliminated just yet<\/li>\n<\/ul>\n<\/div>\n<\/div>\n<\/div>\n<div class=\"pages_block\">\n<div data-click-id=\"d7e85393-de49-4ab6-8958-f0e9e7d3c5a5\">\n<div class=\"HTMLContentstyles__Wrapper-hv2w60-0 fgnwfi\">\n<p id=\"d7e85393-de49-4ab6-8958-f0e9e7d3c5a5\" style=\"text-align: justify;\">The value stream mapping also identifies the time actually spent in adding value and the time the product spends in storage or transport. Time in storage or transport is waste and should be eliminated.<\/p>\n<p>&nbsp;<\/p>\n<figure id=\"attachment_55\" aria-describedby=\"caption-attachment-55\" style=\"width: 988px\" class=\"wp-caption aligncenter\"><img decoding=\"async\" class=\"wp-image-55 size-full\" src=\"https:\/\/libraryresources.nse.org.ng\/wp-content\/uploads\/sites\/17\/2026\/03\/ValueStreamMapParts.png\" alt=\"Diagram shows the different parts of a Value Stream Map of material and information flow. The Information flows from customer to production control to supplier. The supplier then flows into material flow throuh the processes until the product is shipped to the customer. The Value Stream Map shows metrics of each step in the process including Cycle Time, Uptime, and Lead Time.\" width=\"988\" height=\"641\" srcset=\"https:\/\/libraryresources.nse.org.ng\/industrialengineeringintro\/wp-content\/uploads\/sites\/17\/2026\/03\/ValueStreamMapParts.png 988w, https:\/\/libraryresources.nse.org.ng\/industrialengineeringintro\/wp-content\/uploads\/sites\/17\/2026\/03\/ValueStreamMapParts-300x195.png 300w, https:\/\/libraryresources.nse.org.ng\/industrialengineeringintro\/wp-content\/uploads\/sites\/17\/2026\/03\/ValueStreamMapParts-768x498.png 768w, https:\/\/libraryresources.nse.org.ng\/industrialengineeringintro\/wp-content\/uploads\/sites\/17\/2026\/03\/ValueStreamMapParts-65x42.png 65w, https:\/\/libraryresources.nse.org.ng\/industrialengineeringintro\/wp-content\/uploads\/sites\/17\/2026\/03\/ValueStreamMapParts-225x146.png 225w, https:\/\/libraryresources.nse.org.ng\/industrialengineeringintro\/wp-content\/uploads\/sites\/17\/2026\/03\/ValueStreamMapParts-350x227.png 350w\" sizes=\"(max-width: 988px) 100vw, 988px\" \/><figcaption id=\"caption-attachment-55\" class=\"wp-caption-text\">Figure 9.2: Value Stream Map<\/figcaption><\/figure>\n<h1><a id=\"Flow\" href=\"\"><\/a>Continuous flow<\/h1>\n<div class=\"pages_block\">\n<div data-click-id=\"92972bc3-b642-4289-bcdb-9365df58c8ad\">\n<div class=\"HTMLContentstyles__Wrapper-hv2w60-0 fgnwfi\">\n<p id=\"92972bc3-b642-4289-bcdb-9365df58c8ad\" style=\"text-align: justify;\"><a class=\"medium-editor-link-added\" href=\"http:\/\/www.mmsonline.com\/articles\/picture-perfect-manufacturing\" rel=\"noopener noreferrer\">Picture-Perfect Manufacturing<\/a>, from MMS Online, describes how Stremel Manufacturing, in Minneapolis, Minnesota, used current state maps and future state maps to make sure that waste-reduction initiatives \u201cimprove the overall flow rather than merely optimize individual steps.\u201d<\/p>\n<p><span style=\"text-align: justify;\">In continuous <\/span><b style=\"text-align: justify;\">flow,<\/b><span style=\"text-align: justify;\">\u00a0a product never waits but flows continuously through the manufacturing system, thus eliminating time in storage and in transport. Batches and queues should be eliminated. If products move through the production systems in batches, then the first item in a batch must wait until the last item in a batch is completed before it moves to the next processing time; batches mean product spends time waiting, and that time is waste. The presence of queues mean that a product was completed at a previous processing step before the next step was ready for more input. Since the final step of the production process is shipping the product to customers, product should be produced at the rate that meets the market demand. The principle can be applied in the production of services also.<\/span><\/p>\n<p><span style=\"text-align: justify;\">One barrier to flow and one reason for using batches is the time necessary to switch the production facility from producing one kind of product to producing another, which is referred to as <strong>setup<\/strong><\/span><span style=\"text-align: justify;\">.\u00a0 <\/span><a style=\"text-align: justify;\" href=\"http:\/\/www.mmsonline.com\/articles\/setup-reduction-at-the-heart-of-lean-manufacturing\">Setup Reduction: At the Heart of Lean Manufacturing<\/a><span style=\"text-align: justify;\">, also from MMS Online, describes how Richards Industries, a manufacturer of specialty valves in Cincinnati, Ohio, reduced its setup times from an average of 50 minutes to 27 minutes. This reduction enabled them to reduce the typical batch size from 200 to about 20 to 30.<\/span><\/p>\n<p style=\"text-align: justify;\"><span style=\"text-align: justify;\">Flow can be improved by eliminating bottlenecks as shown by the following example from World War II as described by in Methods of Operations Research <a class=\"footnote\" title=\"Morse, P., &amp; Kimball, G. (1951). Methods of operations research (1st ed., rev.). Cambridge: Published jointly by the Technology Press of Massachusetts Institute of Technology, and Wiley, New York.\" id=\"return-footnote-56-1\" href=\"#footnote-56-1\" aria-label=\"Footnote 1\"><sup class=\"footnote\">[1]<\/sup><\/a>.<\/span><\/p>\n<\/div>\n<\/div>\n<\/div>\n<div class=\"pages_block\">\n<div data-click-id=\"b007321d-9bbc-4119-a1c9-1cc7ed273e39\">\n<div class=\"HTMLContentstyles__Wrapper-hv2w60-0 fgnwfi\">\n<blockquote id=\"b007321d-9bbc-4119-a1c9-1cc7ed273e39\">\n<p style=\"text-align: justify;\">An operations research worker during his first day of assignment to a new field command noticed that there was considerable delay caused by the soldiers having to wait in line to wash and rinse their mess kits after eating. There were four tubs, two for washing and two for rinsing. The operations research worker noticed that on the average it took three times as long for the soldier to wash his kit as it did for him to rinse it. He suggested that, instead of there being two tubs for washing and two for rinsing, there should be three tubs for washing and one for rinsing. This change was made, and the line of waiting soldiers did not merely diminish in size; on most days no waiting line ever formed.<\/p>\n<\/blockquote>\n<\/div>\n<\/div>\n<\/div>\n<div class=\"pages_block\">\n<div data-click-id=\"7ea04d3f-633e-4f28-ab2a-376c4e7946a7\">\n<div class=\"HTMLContentstyles__Wrapper-hv2w60-0 fgnwfi\">\n<p id=\"7ea04d3f-633e-4f28-ab2a-376c4e7946a7\" style=\"text-align: justify;\">A <b>bottleneck<\/b> is the narrowest part of a bottle and limits the flow in or out of the bottle. In the original situation with only two tubs for washing, the lines in front of those tubs would have been long, indicating that the wash tubs were the bottleneck, that is, the place in the production process with the least capacity. If washing took three minutes and rinsing took one minute, two wash tubs can serve 40 soldiers per hour while two rinse tubs can serve 120 soldiers per hour. With the new configuration, three wash tubs can serve 60 soldiers per hour, the same service rate as one rinse tub.<\/p>\n<p><span style=\"text-align: justify;\">Bottlenecks can be identified by looking for places where <\/span><b style=\"text-align: justify;\">WIP (Work in Progress)<\/b><span style=\"text-align: justify;\"> piles up and create queues. The processing rate at a bottleneck can be increased by reducing the time to process one item or by adding more processing capability. As a bottleneck\u2019s rate is improved, WIP in front of the bottleneck will disappear, but another bottleneck may now appear.<\/span><\/p>\n<\/div>\n<\/div>\n<\/div>\n<div class=\"pages_block\">\n<div data-click-id=\"9ad0e705-e5f3-405a-a8be-02888e084854\">\n<div class=\"HTMLContentstyles__Wrapper-hv2w60-0 fgnwfi\">\n<h1><a id=\"Pull\" href=\"\"><\/a>Pull and Continuous Improvement<\/h1>\n<div class=\"pages_block\">\n<div data-click-id=\"7930d0b8-861d-45fe-a00f-15243799ef1c\">\n<div class=\"HTMLContentstyles__Wrapper-hv2w60-0 fgnwfi\">\n<p id=\"7930d0b8-861d-45fe-a00f-15243799ef1c\" style=\"text-align: justify;\">In a lean system, no product or service is produced until a customer asks for it, that is, product is pulled not pushed through the system. Some product must be maintained in sales places to meet immediate demand, but reduction in lead time through improvements such as daily deliveries reduces the amount of stock kept on hand and allows more variety in stock.<\/p>\n<p style=\"text-align: justify;\"><span style=\"text-align: justify;\">Lean systems constantly seek perfection by working to continuously improve. An organization should not compete against its competitors. If benchmarking shows the company is doing better than its competitors, it should not relax.\u00a0 As Womack and Jones state in their\u00a0 preeminent\u00a0 book on lean operations, <\/span><i style=\"text-align: justify;\">Lean Thinking<\/i><span style=\"text-align: justify;\"> <a class=\"footnote\" title=\"Jones, D. T., &amp; Womack, J. P. (2014). Lean thinking: Banish waste and create wealth in your corporation. Place of publication not identified: Free Press.\" id=\"return-footnote-56-2\" href=\"#footnote-56-2\" aria-label=\"Footnote 2\"><sup class=\"footnote\">[2]<\/sup><\/a>, state:<\/span><\/p>\n<\/div>\n<\/div>\n<\/div>\n<div class=\"pages_block\">\n<div data-click-id=\"b065128c-98e7-418a-8fec-7b1f5f70ef7c\">\n<div class=\"HTMLContentstyles__Wrapper-hv2w60-0 fgnwfi\">\n<blockquote id=\"b065128c-98e7-418a-8fec-7b1f5f70ef7c\"><p>To hell with your competitors; compete against perfection by identifying all activities that are muda and eliminating them.<\/p><\/blockquote>\n<\/div>\n<\/div>\n<\/div>\n<div class=\"pages_block\">\n<div data-click-id=\"03537f82-d09b-48d4-b4c4-a1699078e2be\">\n<div class=\"HTMLContentstyles__Wrapper-hv2w60-0 fgnwfi\">\n<p id=\"03537f82-d09b-48d4-b4c4-a1699078e2be\" style=\"text-align: justify;\">In addition to the tools listed above, industrial engineers use a lot of other tools to continuously try to reduce wastes in a production or service system.\u00a0 You will learn about these tools throughout your industrial engineering curriculum.<\/p>\n<h1><a id=\"Exercise\" href=\"\"><\/a>Exercise<\/h1>\n<p><code>The original version of this chapter contained H5P content. You may want to remove or replace this element.<\/code><\/p>\n<\/div>\n<\/div>\n<\/div>\n<\/div>\n<\/div>\n<\/div>\n<\/div>\n<\/div>\n<\/div>\n<hr class=\"before-footnotes clear\" \/><div class=\"footnotes\"><ol><li id=\"footnote-56-1\">Morse, P., &amp; Kimball, G. (1951). Methods of operations research (1st ed., rev.). Cambridge: Published jointly by the Technology Press of Massachusetts Institute of Technology, and Wiley, New York. <a href=\"#return-footnote-56-1\" class=\"return-footnote\" aria-label=\"Return to footnote 1\">&crarr;<\/a><\/li><li id=\"footnote-56-2\">Jones, D. T., &amp; Womack, J. P. (2014). Lean thinking: Banish waste and create wealth in your corporation. Place of publication not identified: Free Press.  <a href=\"#return-footnote-56-2\" class=\"return-footnote\" aria-label=\"Return to footnote 2\">&crarr;<\/a><\/li><\/ol><\/div>","protected":false},"author":1,"menu_order":9,"template":"","meta":{"pb_show_title":"","pb_short_title":"","pb_subtitle":"","pb_authors":[],"pb_section_license":""},"chapter-type":[],"contributor":[],"license":[],"class_list":["post-56","chapter","type-chapter","status-publish","hentry"],"part":21,"_links":{"self":[{"href":"https:\/\/libraryresources.nse.org.ng\/industrialengineeringintro\/wp-json\/pressbooks\/v2\/chapters\/56","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/libraryresources.nse.org.ng\/industrialengineeringintro\/wp-json\/pressbooks\/v2\/chapters"}],"about":[{"href":"https:\/\/libraryresources.nse.org.ng\/industrialengineeringintro\/wp-json\/wp\/v2\/types\/chapter"}],"author":[{"embeddable":true,"href":"https:\/\/libraryresources.nse.org.ng\/industrialengineeringintro\/wp-json\/wp\/v2\/users\/1"}],"version-history":[{"count":1,"href":"https:\/\/libraryresources.nse.org.ng\/industrialengineeringintro\/wp-json\/pressbooks\/v2\/chapters\/56\/revisions"}],"predecessor-version":[{"id":57,"href":"https:\/\/libraryresources.nse.org.ng\/industrialengineeringintro\/wp-json\/pressbooks\/v2\/chapters\/56\/revisions\/57"}],"part":[{"href":"https:\/\/libraryresources.nse.org.ng\/industrialengineeringintro\/wp-json\/pressbooks\/v2\/parts\/21"}],"metadata":[{"href":"https:\/\/libraryresources.nse.org.ng\/industrialengineeringintro\/wp-json\/pressbooks\/v2\/chapters\/56\/metadata\/"}],"wp:attachment":[{"href":"https:\/\/libraryresources.nse.org.ng\/industrialengineeringintro\/wp-json\/wp\/v2\/media?parent=56"}],"wp:term":[{"taxonomy":"chapter-type","embeddable":true,"href":"https:\/\/libraryresources.nse.org.ng\/industrialengineeringintro\/wp-json\/pressbooks\/v2\/chapter-type?post=56"},{"taxonomy":"contributor","embeddable":true,"href":"https:\/\/libraryresources.nse.org.ng\/industrialengineeringintro\/wp-json\/wp\/v2\/contributor?post=56"},{"taxonomy":"license","embeddable":true,"href":"https:\/\/libraryresources.nse.org.ng\/industrialengineeringintro\/wp-json\/wp\/v2\/license?post=56"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}