Unit 2
Structure 2.1 Introduction
2.1.1
Advanced Methodologies of Production
Advanced Methodologies of Production
Use of Computers in Design – CAD Computer Integrated Manufacturing
2.1.1.1 2.1.1.2
2.2 Splitcase Order Fulfillment Methods and Mechanization
2.2.1 Order Picking Methods 2.2.2 Sorting and Routing 2.2.3 Order Packing Methods 2.2.4 Classification Schemes
2.2.5 Choice of Optimal Fulfillment Strategies 2.3 Communication of Picking Directives 2.4 Order Picking and Packing Economics
2.4.1 Space and Storage Equipment Costs 2.4.2 2.4.3
Storage costs per annual cube movement Storage Density Vs. Velocity
2.5 Capital costs for online Storage
2.5.1 Mechanization Costs – for Assembly and Packing 2.5.2 Picking and Packing Costs
2.5.3 Order Assembly and Packing System Costs 2.5 Summary TQ
Answer to SAQ and TQ
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2.1 Introduction
In this unit, we discuss advanced technologies of production; use of CAD and CIM to facilitate production. Classification of material, their storage and how assembly lines are fed with picking materials using mechanized systems for achieving high efficiencies are discussed. Also discussed are the costs at various stages and the way a balance is struck for optimization. Learning Objective:
· New concepts of manufacturing technology.
· Use of computers in Design, of products, components, assemblies, and how
their analyses help in producing better products
· Importance of information flow which should be continuous, accurate and
timely.
· Advanced methodologies of mechanization that help in improving quality and
reducing throughput time, ·
Computerised Integrated Manufacturing systems takes care of various processes like scheduling, routing, inventory and optimizes the usage of space and storage systems. ·
Packaging and movements of materials both inside the plant and external distribution points for raw materials and finished products
2.1.1 Advanced Methodologies of Production
Production systems contain principally, the machinery, which are used to transform materials to the desired shapes, having the requisite properties –induced into them for obtaining specific performance parameters so that product when assembled allows the user to obtain or derive outputs i.e customer satisfaction. This process calls for obtaining raw materials, store them, and move them from one stage of operation to the next sometimes outside the plants. Tracking them throughout the process the supply chain verifying the completion of operation is a stupendous task. Optimisation at every stage is necessary to derive competitive advantage. Advanced methodologies in aspects like material handling, scheduling, Just In Time, Lean Manufacturing, packaging, logistics get the support of data base management systems on line transmission and processing of information that initiate and follow activities. With advancement in IT processing of
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operations has become fast and accurate. These bring in economies which have made it possible to manufacture and deliver high quality products on a global scale. We will consider them in detail in the following pages.
2.1.1.1Use of computers in design CAD
Designers of products are increasingly depending on Computer Aided Design. The software aids in creating or modifying an existing design. The images can be maneuvered on the screen. Images of different components can be seen as ‘assembled’; sections taken and relative positions can be checked to great accuracies. Views can bee made seen from different angles and positions, so that the visualization process of the designed component/product helps the designer to suggest alternatives to the customer and the production department. The drawings can be sent via intranet or internet to the concerned persons and their opinions taken. Corrections and incorporations can be made very quickly. The database can be prepared, updated continuously and their access to executive. The efficiency of designers increases by nearly 5 times The software can generate the volume, weights of components as also other engineering parameters like centre of gravity, deflections under estimated loads, and various other design parameters on complicate forms – either single components or assemblies Laborious mechanical drawings need not be drawn. nor complicated calculations done. This aids in reducing the time required to make a design or modify a product and thus concept market period gets drastically cut. 2.1.1.2 Computer Integrated Manufacturing
Integration occurs when a broad range of manufacturing and supporting activities are linked. Activities include engineering design, production planning, shop control, order processing, material control, distribution etc. Information flow across all functions takes place with the help of computers. Transmission, processing, distribution and feed back happen almost in real time so that intended activities are conducted rapidly. This process helps in rapid production and also reduce indirect costs. As response times decrease, customer satisfaction increases resulting in better business. CIM helps in avoiding accumulation of materials resulting in better throughput and better utilization of space. Bar coded labels that accompany materials
contain instructions for processing them which are read by sensing devices and display the status on monitors. This information is available to all concerned personnel responsible in planning,
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marketing etc. so that they will be aware of the status of any order and if expediting is needed to meet deadlines, they will be able to seek intervention. Identifying shortages, ensuring faster deliveries becomes easy with CIM.
2.2 Splitcase Order Fulfillment Methods and Mechanisation
This system looks at situations when bulk supplies in full cases to one or more destinations are not done. Fulfillment of orders which need different merchandise in different quantities requires that ‘cases’ will have to be split, and pieces picked, repacked in cartons and ship to the customer. . Mechanisation helps in improving identification, pickup and repacking the materials in addition to relieving monotony of the workers. A few strategies of achieving this objective optimally are discussed here. 2.2.1
Order Picking Methods
Items as per customer requirements have to be picked and packed in a logical manner and
assigned to personnel so that their productivity is maximized. Accuracy of fulfillment of order is ensured by two basic factors
a) Order Extent it is defined as the number of order to be picked simultaneously by a
picker in an assignment. This is categorized as discrete order picking in which case a single order is selected at a time; and Batch order Picking in which case the merchandise requirements of many orders are put together and selected for pick up in the geographical area which is covered in a single pass.
b) Coverage Extent it is the physical area to be traversed by the picker in selecting
merchandise for an assignment within the picking system. The personnel pick up the merchandise from a zone the zone being a contiguous area with different picking locations. The boundaries may be fixed or dynamically adjusted to accommodate either personnel or customers. This zone is identified within the picking area. In the other method called tour picking the entire picking area is considered for picking merchandise. Either of the strategies is adopted to meet the constraints or opportunities which maximize employee productivity and the customers’ needs.
2.2.2 Sorting and Routing
Sorting is done for the purpose of easing the operation of matching orders, merchandise
and the customers for whom they are done. This activity can be done as and when orders are
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picked Sort Immediate or by merging a number of order and batches are made to consolidate the priorities for execution. This method is called Merge and Sort. The strategy used depends on the total area of the zone, the number of orders, and the type of merchandise. and the economics of balancing all the above.
When orders are routed among those zones where picks are required we call them Routing
the picks. When orders are routed from zone to zone, in a particular order, whether any picks are there or not, we call them chaining. When multiple zones are covered simultaneously in different zones we call them parallel routing. As can be discerned, no one single method is suitable for actual situations on site. They are formulated as a strategy for optimization of resources in view of the constraints.
2.2.3 Order Packing Methods
Order fulfilling methodology covers one more aspect i.e. the order packing methods. When split case is executed it becomes necessary that the merchandise is repackaged for shipment to meet the requirements of the customers. In the first method they are packed as they are picked. This is applicable in cases where the merchandise is usable by the customer directly and when the tools and packaging materials are available with the picker and he can pack them throughout the picking area.
2.2.4 Classification Schemes
In this section you will come to know about the coding of various methods of split picking and packing. The letters will uniquely identify the method intended to be used and all personnel in the process will know disposition status of the merchandise.
D iscrete Order Picking or B atch Order Picking Letter D or B is used Z one Picking or Tour Picking
Pack Immediate or Assemble and Pack BS Batch Order Picking Sort Immediate BM Batch Order Picking – Merge & Sort ZR Zone Picking with Routing ZC Zone Picking with Chaining
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ZP Zone Picking in Parallel
For example, BSDZCA means Batch Order Picking Sort ImmediateDiscrete Order Packing Zone Picking with Chaining and Assemble.
With this type of coding 24 ways of representing the type of split order picking and packing are identifiable.
2.2.5 Choice of Optimal Fulfillment Strategies
The choice of order fulfillment strategy depends upon the predominant order characteristics and category of distribution. They are determined by General order characteristics such as
a) number of lineitems; b) quality of pieces per line item
General order categories are
a) Wholesale Distribution – usually large number of pieces of a few items; b) Retail Distribution – orders for large quantities for a large number of items; c) Direct Marketing orders for a small quantity;
d) Consumer Distribution small quantities of different items for purposes of evaluation,
promotion and consumption
The performance measures to be satisfied by the choice of strategy are to minimize the costs involved and maximize desirable characteristics.. They are
a) b) c) d) e) f)
Minimise the cost of pick and pack for every order; Minimise the cost of shipping per order, Reduce the time required per cycle; To increase the fill rate
Improve Accuracy of the elements of the process Traceability and accountability of all transactions..
Advanced technology involving Bar Coding, feeding on line data, high speed processing an distribution of information across all nodes of the supply chain help in improving efficiency, reduce costs and improve customer satisfaction.
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Self Assessment Questions 1
1 Mechanisation helps in improving __________, _________ and ___________the materials in addition to relieving monotony of the workers.
2. When multiple zones are covered simultaneously in different zones we call them __________ _________.
2.3 Communication of Picking Directives
For efficient process of order picking by personnel, communication plays a vital role in any organisation. The directives they need have to be accurate, timely and sufficient. With the help of computers and automation this task has become reliable to the extent that dependence is almost total. So, the method selected to communicate the directives for picking will certainly impact on the performance measures, which represent the consequences of the activities indulged in. A few of the techniques are discussed here.
1. Reports Customers’ order either in the printed format generated by the customer or converted to one by the marketing department, pick lists, packing slips, stock location reports, delivery notes. The reports flow along with the orders and when split are distributed for parallel picking..
a.
Labels – These are used to direct order pick locations in addition indicate picking activity. These labels are bar coded for item sorting and order verification. These are used mostly for Discrete order or Batch selection methods. b.
Radio Frequency Terminals These are used in combination barcoded shipping labels to identify the orders for purposes of sorting and routing. They need classification, coding and bar coding for identifying orders for routing and sorting. c.
Display Lights – These computer activated lights are used to direct order selectors to items and locations to pick order or batch requirements. Items are ‘put’ in designated locations and the data read and the light helps the sorting of the items as per orders. They call for the attention of the personnel and alert them.
Self Assessment Questions: 2
1. Directives they need have to be ________, _______ and ______.
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2.4 Order Picking and Packing Economics The main cost factors can be divided into
two categories Capital Costs non recurring and operating costs recurring. The first one includes facilities, material handling systems, weighing systems and other supporting and facilitating goods which are used over a long time. The operating costs include labour, consumable supplies, insurance, utilities, taxes etc. which are generally to the scale of operations. Some more costs which can be called incidental costs are those associated with damages, resolution of errors, return handling, inventory shrinkage etc.
2.4.1 Space and Storage Equipment Costs Split case picking and packing functions
and the space required for them can be broadly categorized as
a) on line storage for inventory; b) replenishment aisles; c) picking aisles(work area); d) packing work space;
e) material handling space. Activity levels are used to determine the methods of on line
storage for managing on line storage. They include Pallet Racks, Case Flow Rack, Bin Shelving and Carousel. They are used depending on the size, quantities, patterns of withdrawal and velocity.
2.4.2 Storage costs per annual cube movement Pallet storage is the lowest cost
option per
cubic metre movement as investments in racking, flow rail etc. get earlier two options. Amortised over a long period while transporting huge volumes. Case flow racks are only slightly costlier. Bin storage is relatively costlier than the earlier two. The capital cost of Carousel is significantly costlier than all the other systems though ate of movement is considerably higher.
2.4.3 Storage Density Vs. Velocity
Storage Density refers to quantity of material or number of items that can be stored in a unit of volume say 10 Cub.Metre. The type of storage we provide depends on the average duration of storage and the frequency of retrieval. One more factor is to be considered is whether the move different materials to a central location for purposes of assembly or further transmission or to the customer direct. Replenishment and pickup activities also matter when we consider the type of
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storage we provide. If they have to be conducted simultaneously Cash Flow Rack becomes the preferred choice. Velocity refers to the speed with which materials are moved into the storage and how fast they are required to be moved to the next point in the supply chain. When we deal with SplitCase Order Fulfillment situations the variety of items that need to go into satisfying orders are many, the access to the personnel in the system becomes an important factor in the design of the system. The major costs that are necessary to be incurred for an online storage system are space and the equipment costs. The economics of all the four systems – Pallet Rack, Case Flow Rack, Bin Shelving and Carousel are considered for maximum utilization of space, requisite amount of mechanization and productivity of the personnel.
Self Assessment Questions 3
1. Type of storage we provide depends on the average ___________ and _________.
2,5 Capital costs for online Storage Storage economics are mainly concerned with the
capital cost for on line storage when rationalised with annual item cube movement. Capital costs are those for the space, building, material handling equipments, bins, pallets, pallet loading systems, computer hardware and software for identifying and processing information about the storage cost . The main concern is the provision for picking, retrieval and packing . The supporting and efficiency enhancing fixtures needed for the efficient use of space and heavy equipments should be addressed. The extent of mechanization depends on the expected returns in them. Many times mechanization will not solve some fundamental problems of basic design of the system, inadequate forecasting or inappropriate methodologies. It will be found that capital costs which are quite huge fail to result in increased productivity and will be a drain on the economics of the operation,
2.5.1 Mechanization Costs – for Assembly and Packing Failure of the splitcase order
Assembly and Packaging systems occurs mainly due to two reasons a) Tote Sorting b) Item Sorting. Totes containing the picked merchandise area moved from the selected zone. These are received for sorting where the sorter automatically transfers all totes of a given order on a conveyor which supplies them to the packing station. The stations which perform this activity will have their
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workload assigned dynamically. The Item Sorting System received the Totes with picked merchandise are transported to one more induction stations where individual items are removed. These items area inducted into an item sorter. The sorter will be in the form of tilt tray or a cross belt. Individual items get sorted and sent to chutes which carry the items for assembly and packing. The discharge takes place at the Pack stations. Some times belt conveyors are used for Sorting and transporting. In such cases chutes may become redundant. It is to be noted that type of merchandise, their quantities determine the method for the intended operations. The capital costs in adopting one system to another will vary and utilization and productivity are factors which determine the choice. However, it is advisable that provision for alternates may be planned so that modifications do not become very costly.
2.5.2 Picking and Packing Costs These activities require a good deal of human intervention,
thus needing a number of people. Distribution centres where picking and packing activities take place will measure performances on the basis of pieces per manhour or order lines per manhour. Inevitably, these get linked to orders. There is a large variation in the quantities per order, variety of merchandise, waiting lines and other characteristics of the orders being filled. The orders might be wholesale, retail, direct or consumer. Productivity measures though dependent on pieces per hour or lines per hour will have to be adjusted to suit the peculiarities of the situation. The extent of mechanization also has to be considered. Costs involved – both in terms of capital and labour intensive activities should get suitable representation of the cost structure.
2.5.3 Order Assembly and Packing System Costs Assembly is done manually and
hence needs a well trained workforce. The variety of merchandise that arrive from totes either via the chute or trays or cross belt have to be accurately identified and placed for Assembly. Though every care would have been taken gaps in the information flow would still hold up the operations. Reducing inventory at this level is critical to productivity. Feed back systems should b e very efficient to rectify errors as and when they occur. Main costs involved at this stage are the manpower and capital costs would not be heavy. Packing systems may be semiautomatic or manual. Fully automatic systems may not be advisable for Order Assembly situation unless quantities are large and requirements are for longer periods.
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Self Assessment Questions: 4
1. Many times ___________will not solve some fundamental problems of basic design of the system, ___________or inappropriate methodologies.
2. Some times bulk handling_______________ systems area used for _______.
3. ____________ though dependent on pieces per hour or lines per hour will have to be adjusted to suit the peculiarities of the situation.
2.5.4 Summary
New concepts of manufacturing technology and use of computers in Design, of products, components, assemblies, help in producing quality products. Information flow which should be continuous, accurate and timely is an important element introduction Advanced methodologies of mechanization help in improving quality and reducing throughput time,
Computerised Integrated Manufacturing systems takes care of various processes like scheduling, routing, inventory and optimizes the usage of space and storage systems. Packaging and movements of materials both inside the plant and external distribution points for raw materials and finished products is an important function in the supply chain.
Terminal Questions:
1. Explain how CAD and CIM helps in improving productivity 2. How split case orders processes improve customer satisfaction? 3. Explain the difference between Storage Density and Velocity. 4. Give reasons as to why failures occur in split case order assembly.
Answers To Self Assessment Questions and TQs Self Assessment Questions 1
1. Identification, pickup and repacking 2. Parallel, routing
Self Assessment Questions 2
1.
Accurate, timely and sufficient
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Self Assessment Questions 3
1.
Duration of storage and the frequency of retrieval.
Self Assessment Questions 4
1. 2. 3.
Mechanization, inadequate forecasting. Belt conveyors, sorting and transporting. Productivity measures.
Answers To Terminal Questions
1. 2. 3. 4.
Refer to 2.2.1 Refer to 2,2,3 Refer to 2.4.3 Refer to 2.5.1
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