MS-5 1.
Elab Elabor orat ate e the the con conce cept pt of syst system ems s Life Life-c -cyc ycle le in oper operat atio ions ns Mana Manage geme ment nt
Ans:
Concept of systems Life-cycle: Life-cycle: The life-cycle life-cycle concept concept or `womb `womb to tomb' concept concept draws analogy from living organisms. It assumes that every system (product) has a definite life-cycle and it passes through growth, maturity, saturation and decline phases. Figure V shows a typical life-cycle of a product. Similar pattern could exist for the entire production systems. Lifecycle concept enables us to understand various decisions and their inter-dependence in a better perspective. For example if some of the strategic decisions like product selection or plant location, which are made at the early stages of systems life-cycle are wrong, then these would continue to influence day-to-day operations planning and control decisions adversely and no amount of day-to-day effectiveness will be able to undo the damage done by poor decisions at initial stages of life-cycle. This concept also enables us to be alert to the external environment and start phasing out a dying product and substitute, it with a new product well in time so that continued survival of the organisation can be planned. Figure V shows how introducing new product well in time can cause long-term survival of the organisation even if individual products follow life-cycle pattern. Life span of a product may vary from few months (such as fashion goods) to few decades. Stages in Systems Life-cycle: The eight stages stages of the syste system m life-c life-cyc ycle le along along with with the associated key decisions to be made at each stage. Some of the initial decisions like product selection, technology selection, location and layout selection are of strategic importance. Once the system has achieved steady state-most on-going organisation we work in are probably at that stage-then most problems of operations management are of tactical or operational nature. Short-term planning and control and cost reduction strategies are the main focus at that stage. The steady steady state state experi experienc ences es minor minor pertur perturbat bation ions s due to extern external al and intern internal al factor factors. s. Moderate level changes can be accommodated by updating and revising of the previous decisions. When the system cannot adjust to even major revisions due to extreme changes in external environment, then the systems must come to end-through liquidation or through sale or merger. Termination or phasing out of operations may be sometimes deliberate. Life-cycle Costing: A very important concept in costing has emerged in recent years-that of life-cycle costing. It says that when we evaluate the cost implications of our decisions we should should not consider consider the short-term short-term cost alone but the entire costs during the life-cycle life-cycle of the system system and equipment. equipment. Thus long-term long-term cost repercuss repercussion ion must be examined rather than immediate short-term alone. Such a concept may change our perspectives and seemingly good decisions may not remain attractive if life-cycle costs are computed. For example while purchasing a machine, the short-term cost may mean only initial purchase price and we may be tempted to buy a cheaper equipment or machine. It may however require too much repair, maintenance and operating expenses. If all these costs including initial costs are compared during the life-cycle of the machine, we may find that an expensive machine with very little maintenance repair and operating cost may be preferred alternative over initially inexpensive but `costly-to maintain' machine. Thus while making important decisions regarding design and planning aspects of production systems we should consider life-cycle costs. These could even be converted to present values by discounted cash flow techniques, accounting for the time value of money.
Stages of Life cycle and key decisions Stage
Key decisions
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1.
Birth of of th the sy system
Identification of of co corporate go goals se selection of of th the Product
2.
Productio Production n design design and process se selection
Technologi Technological cal design of product, product, selection selection of manufacturing te technology se sequence of of ma manufacturing
3. Design Design of the the produ producti ction on System
2.
Facili Facility ty loca locatio tion/l n/lay ayout out,, desig design n for for quali quality, ty, demand demand forecasting
4.
Manning th the sy system
Job st structuring al allocation, as assignment me method de design, Work measurement, payment systems
5.
System start up
How to overcome initial problems, how to achieve fu full capacity.
6.
System stem in stea stead dy sta state te
Oper peratio ation nal deci decisi sio ons, ns, co cost red reduc ucti tion on stud studie ies, s, Improving system performance to look after day-today problems
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Revi Revisi sion on of the the sys syste tem m
Upda Updati ting ng vari variou ous s dec decis isio ions ns in the the lig light ht of exte extern rnal al Changes
8.
Death of the system
How to phase out, salvage resources, sustain by starting new product etc.
Defi Define ne wor work k mea measu sure reme ment nt.. Wha Whatt are are the the var vario ious us meth method ods s of of wor work k mea measu sure reme ment nt? ? Discuss work sampling.
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Ans:
Work measurement: Work measurement is concerned with the determination of the amount of time required to perform a unit of work. It provides management with a basis for comparison of alternative methods, and also a basis for initial manning. Moreover, it makes available the necessary data for effective planning and scheduling and provides a basis for wage and salary administration especially for devising sound incentive schemes. Various Various methods methods of work measurement: measurement: The various methods and techniques of work measurement are as follows: (a) Time study (b) Work sampling (c) Pre-determined motion-time system (PMTS) (d) Analytical estimating (e) Synthesis from standard data (f) MOST Time study: study: Basic time study equipment consists of a stop watch, a study board, pencils, a pocket calculator (optional) and measuring instruments for distance and speed (such as a ruler, tape measure, micrometer and technometer/revolution counter). The decimal-minute stop watch has been adopted as standard equipment. It may take you some time to get used to this system as most of us are used to the seconds system Regular checks are necessary for monitoring the accuracy of the watch at regular intervals. In some situations, much more expensive type of equipment like motion picture camera could be used. But we don't think it to be feasible in our country, as yet. As regards the time study board, an ordinary clip-board used by us when appearing in examinations could suffice. However, do not forget to keep at least two or three sharpened pencils or pens/dot-pens along with you while conducting the study. If one pencil point breaks, then you have the other one ready. We can’t afford to go in for sharpening the pencil because this would lead to erroneous recording of the elements. Perhaps we might not be able to appreciate this trivial point now. But we will realise your helplessness. If we experience such a situation while conducting a time study yourself. Work sampling: sampling: The origin of this technique is credited to L.H.C. Tippet. He used the method of ‘snap reading for determining the causes of loom stoppages in Textile factories in 1935 while working for the British Cotton Industry Research Institute. Since then, the technique has been successfully applied in many different situations under such names as Ratio Delay Study, Random Observation Method, Observation Ratio Study, Activity Sampling and Work Sampling. Work Sampling is a fact-finding tool. It is a measurement technique for quantitative analysis, in terms of time, of the activity of operators, machines, or of any observable state or condition of operation. This tool is particularly useful when information is urgently needed about men or machines, especially in the analysis of non-repetitive or irregularly occurring activity where no complete method and frequency description is available. Work sampling can be used to study almost almost any type type of work: work: repeti repetitiv tive e and non-re non-repet petitiv itive, e, factor factory y or office office,, execut executive ive or supervisory, clerical or engineering, handlers, salesmen, nurses and what have you. Work sampling is a method of randomly observing work, noting state or condition of the object being studied. From the proportions of observations in each category, inferences are drawn conc concer erni ning ng the the tota totall work work acti activi vity ty unde underr stud study. y. It can can be used used for for fact fact-f -fin indi ding ng,, work work measurement and methods analysis. Some uses of Work Sampling: Work Sampling provides a way to: (i) (i) obta obtain in inf infor orma mati tion on abo about ut eit eithe herr cert certai ain n long long cyc cycle le wor work k or non non repe repeti titi tive ve typ type e of job jobs s for which it would be clearly impractical to use continuous observation methods. (ii) (ii) indi indica cate te ifif cert certai ain n acti activi viti ties es sho shoul uld d be stu studi died ed in in deta detail il.. (iii) (iii) help help des desig ign n the the work work loa load d dist distri ribu buti tion on in in form formul ulat atin ing g a new new work work sys syste tem. m. (iv) (iv) stud study y any any oper operat atio ion n for for poss possib ible le meth method ods s impr improv ovem emen ent. t. (v) help establish job content as an aid to job evaluation and employment purposes. (vi) aid aid su superv pervis isor ors s to to org orga anis nise the their ir tim time. (vii) (vii) aid apprai appraisal sal of shop shop effect effective ivenes ness, s, effici efficienc ency, y, safety safety perfor performan mance ce etc. etc. (viii) (viii) provid provide e feedba feedback ck infor informat mation ion abou aboutt compli complianc ance e to state stated d manage managemen mentt policie policies. s. (ix) (ix) assi assist st in in esta establ blis ishi hing ng sta stand ndar ards ds of of perf perfor orma manc nce. e. (x) (x) esta establ blis ish h con contr trol ols s on on lab labou our, r, mate materi rial al or mach machin ine e uti utili lisa sati tion on.. Predetermined Motion Time System (PMTS): Every element of work is composed of some combination of basic human motions. Apart from mental activity, all work can be broken down
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into elements that are usually a fundamental movement of the body or body members. After this analysis stage, the basic motions that have been isolated have a time allotted to them on the basis of predetermined motion times. This is the measurement (or rather premeasured) stage. The synthesis stage involves combining the basic motions in specific combinations and frequencies to form basic elements which would go to complete the total work operation. This method is particularly suited to situations where direct observations may not be possible or it may be some entirely new method of working which, however, is composed of work of basic elements which are standard with a new combination or mix. It is suited to both repetitive as well as non-repetitive work. Analytical Estimating: After the job has been broken down into its constituent elements in certain certain types of non-repetitiv non-repetitive e work, work, we find that analytical analytical estimating estimating serves as best for measuring work. In the analysis stage we find that usually these basic elements are much larger as compared to the elements in PMTS or time study. For the measuring stage, the time, which will be occupied by the element at a specific speed of working, is estimated. Many values may be obtained from the records of previous studies. The synthesis of all such records or data can be clubbed together for meaningful purpose. Synth Synthesi esis s from from Standa Standard rd Data: Data: Now Now here here we find find yet yet anot anothe herr tech techni niqu que e of work work measurement to obtain synthetic times (or synthesised time standards) that are synthesised from from elem elemen entt time times s prev previo ious usly ly obta obtain ined ed from from dire direct ct time time stud studie ies. s. The The anal analys ysis is and and measurement stages are thus conducted prior to the actual study. The technique primarily focuses on the synthesis stage. Most organisations that have had work studies conducted for some time usually build up synthetic tables covering the common elements in their own type of work. You could also refer to some standard tables, but be cautious in adapting it to your own organi organisat sation ions s by duly duly keepin keeping g the frame framewor work k in mind mind for which which the standa standards rds might be applicable. MOST Measurement System: The word MOST stands for Maynard Operation Sequence Technique. The basic assumption here is that for an overwhelming majority of work, there is a common denominator from which work can be studied: the displacement of objects: In fact, all basic units of work are organised for the purpose of accomplishing some useful result by simply moving objects. MOST is a system to measure work by concentrating on the movement of objects. objects. Consequently, Consequently, MOST technique technique is composed composed of the following basic sequence sequence models: The General Move Sequence The Controlled Move The Tool Use Sequence (for the use of common hand tools). In contrast to Methods Time Measurement, PMTS etc., the primary work units are no longer basic motions, but fundamental activities (collections of basic motions) dealing with moving objects. • • •
3.
What are the objectives of value Engineering? Discuss how to organize VE/VA function in a tractor manufacturing firm.
Ans:
Objectives of value engineering: engineering: We Should able to (i) Understand the concept of value engineering (ii) Differentiate between value and cost
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(iii) (iv) (v) (vi) (vii) (viii) (ix)
See value engineering in historical perspective Appreciate the role of value engineering in cost reduction and performance improvement Identify poor value areas in products and systems Learn about the value engineering job plan Appreciate the role of some of the techniques of value engineering Study some cases to see the improvements in product value through value engineering techniques. Identify the behavioural and organisational issues involved in value engineering.
Value Engineering and Value Analysis in a tractor manufacturing firm: Value Engineering (VE) or Value Analysis (VA) is an important and powerful approach for improvement in the perfor performan mance ce of the produc products, ts, syste systems ms or proced procedure ures s and reduct reduction ion in costs costs withou withoutt jeopardising their function. The terms VE and VA are used almost interchangeably. Other terms used to convey the same concepts are Value Assurance and Value Management (VM). L.D. Miles defined Value Analysis in his book Techniques of Value Analysis and Engineering (1961) as "an organised creative approach which has for its purpose the efficient identification of unnecessary cost i.e., cost which provides neither quality, nor use, nor life, nor appearance, nor custom customer er featur features" es".. Variou Various s other other definit definition ions s are propos proposed ed such such as "an organi organised sed systematic study of the function of a material, component, product or service, with the objective of yielding value improvement through the ability to accomplish the desired function at the lowest cost without degradation in quality". Thus the basic objective of VE/VA is to achieve equivalent or better performance at a lower cost while maintaining all functional and quality requirements of tractor. It does this largely by identifying and eliminating hidden, invisible and unnecessary costs. We may simply perceive VE as the systematic application of recognised techniques to identify the functions of a product or service and provide those functions at the lowest total cost. Value Engineering should not be 'treated as a mere cost reduction technique or cheapening of the product. It is more comprehensive and the improvement in value is attained without any sacrifice in quality, reliability, maintainability, availability, aesthetics, etc. It was traditionally applied in the area of hardware projects, such as product design, though these concepts are equally equally applic applicabl able e in softwa software re projec projects, ts, in the syste systems ms and proced procedure ures. s. Recent Recently ly these these concep concepts ts have have been been applie applied d to non tradit tradition ional al areas areas `such `such as urban urban slum slum develo developme pment nt programmes, staff welfare motivation enhancement and courtesy improvement plans. One of the important reasons behind poor value in products, systems and procedures that we come across is the lack of organised effort in devising such systems. Many times the designs are created under highly compressed time frame and the designer may play safe by giving product designs with sole emphasis on technical feasibility and may prescribe thicker, costlier materials and other unnecessary features which are not needed by the customer. Sometimes, ad hoc decisions get permanency due to lack of review of product designs. Often lack, of consultation with others contributes to poor value. Lack of information, wrong beliefs, habits and attitudes are some of the other reasons.
4.
Write rite an essay ssay on Stat Statis isti tic cal Quali uality ty Con Control trol
Ans:
Statistical quality control: control: The some of the statistical quality control methods are as follows:
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Variability: Variability: All products and services have a certain amount of natural variability because of variations in the input as well as imperfections in the process. For example, different quality of raw materials could have been used and different quantities of chemicals could have been used in the process. This process variability may be measured by the process standard deviation v, which indicates how much the products will vary even if the process is in control. Products have to meet specified tolerances imposed by their intended use. Accordingly the natura naturall variab variabili ility ty must must be substa substanti ntiall ally y small smaller er than than the specif specified ied tolera tolerance nce.. Within Within the specified tolerances, a certain amount of process variability is to be expected. However, It is the goal of the statistical process control control to determine when the process variability is getting out of hand; so that corrective action can be taken, preferably before the required tolerances are violated. This is generally achieved by a Control Chart. Control Chart: In order to provide rapid feedback to an ongoing production process, methods somewhat different from acceptance sampling are appropriate. Samples are taken as soon as they are available, rather than waiting for the completion of a lot. This affords the opportunity to detect unplanned changes in the process, shortly after they occur and take .a quick action, such as adjusting the machine. The most common device used for this purpose is Shewart Control Chart introduced in 1931. The control chart is a visual display of the result of an inspection inspection process incorporating incorporating carefully derived limits to indicate indicate unusual unusual behaviour. behaviour. A control chart can be based on categorical information or actual measurement. Accordingly, they are called control chart for variables and control chart for attributes. attributes. Since control chart for variables are more commonly used and more powerful, we will describe them first. The control chart is based on the idea that the average of a sample of several items will tend to cancel cancel out the normal process variability, variability, so that undesirable undesirable changes in the process process will be more visible. Other Control Charts: There are several other control charts, including the p-chart which is used to control the process when the measurement is by attributes. In other words the decision is only to decide whether or not the sample item is acceptable. No measurement is taken. For example in using the GO/NO GO gauges one gets only such a measurement. The p-chart is based on the fraction defective, p, in a sample of n items. If Po represents the normal process defective (i.e. when the process is in control). This is based on the fact that the number of defectives has the binomial probability. The control chart is used just like an X chart, except that the fraction defective p is calculated rather than X for each sample of n items and a lower control limit is often omitted. P0
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This is based on the fact that the number of defectives has the binomial probability. The control chart is used just like an X chart, except that the fraction defective p is calculated rather than X for each sample of n items and a lower control limit is often omitted. Sample sizes are typically larger for p-charts then for X-charts. Since the information content of a yes/no measurement is much smaller than the actual variable measurement, it can only be expected.
5.
Disc iscuss uss the the vario arious us vendo endorr ev evalua aluati tion on and and ra rating ting
Ans:
Vendor evaluation and rating: rating: It is not always easy to identify good suppliers. Records maintained maintained or procured procured from some other, sources sources about the vendors vendors help in their evaluation evaluation and rating. Usually a combinatio combination n of price, price, quality, quality, quantity, quantity, delivery time, service etc. giving
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relevant weightages to these factors is used to rate the vendors. In addition, a checklist can be used to facilitate rating from department standpoints. Some of the points are mentioned below: Reliability 1 Is the supplier reputable, stable and financially strong? , 2 Are the supplier's integrity and ability above doubt? 3 Is the supplier going along with product improvement? 4 Is the supplier's competitive strength. As to price, quality, etc. proved by past experience? Technical Capabilities 1 Can the supplier provide assistance as to application engineering? 2 Can the supplier provide assistance as to analytical engineering? 3 Can the supplier provide design assistance? 4 Can the supplier handle special needs. and contribute to improve product efficiency/basic processes? Convenience 1 Can the supplier help reducing acquisition costs through personal visits, telephone calls, incoming inspections, rejection of defects, spoilage, etc? 2 Can he offer other related products? 3 Is he qualified to help in solving difficult problems? 4 Does the supplier package his product conveniently? Availability 1 Does the supplier assure delivery in time? 2 Are his stocks locally available, and or at short notice? 3 Is the supplier's location advantageous? 4 Can he plan his supply to minimise inventory? 5 Can he be depended on for a steady flow of materials? After-sales Service 1 Does the supplier have a service organisation? 2 Is an emergency service available? 3 Are parts available, when needed Sales Assistance 1 Can the supplier help building mutual markets? 2 Will he recommend our products? 3 Does the use of supplier's product enhance appearance of our products? Vendor Evaluation: Recognising that there is a need for having good vendor, it is essential that supplies, are obtained from vendors after an evaluation of his capabilities. The buyer, who has to do the evaluation, is faced with two different situations; 1 Evaluating the performance before the vendor has delivered anything. 2 Evaluating the performance of vendor after the deliveries have been made. The latter one is normally called Vendor Monitoring and the former Vendor Evaluation. In case of Vendor Evaluation the buyer lacks the direct evidence on the results achieved by the vendor and must get his information in other ways. This includes (1) general reputation of vendor, (2) data from other buyers, (3) vendor surveys. Vendor Rating: Product quality submitted by vendors has always been evaluated and used as a factor in making purchasing decisions. Recently, the evaluation has been formalised by the use of vendor rating formulas which provide a quantitative measure of vendor quality. These ratings are primarily meant to provide an overall quality rating of a vendor for use in reviewing, compar comparing ing,, and select selecting ing vendor vendors. s. Vendor Vendor rating rating is not a tool tool for making making decisi decisions ons on submitted lots. To create a single single numerical numerical quality score is difficult difficult because there are several inputs, each involving its own unit of measure: 1 The lot quality, expressed as lots rejected versus lots inspected. 2 The parts qualities, expressed as per cent defective. 3 The characteristic qualities, expressed in numerous natural units, e.g., rupees per square cm., per cent active ingredient, MTBF, etc. 4 The economic consequences of bad quality, expressed in rupees. The National Association of Purchasing Agents, New York, has published three alternative vendor rating plans: 1 Categorical Plan: This is a non-quantitative system in which buyers hold a monthly meeting to discuss vendors and rate each as plus, minus, or neutral.
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2 Weighted-point Plan: Each vendor is scored on various factors like quality, price, service etc. These factors are weighted and a composite rating is then calculated for each vendor. The details of this performance evaluation scheme are as follows: i) Quality Rating: Quality Rating for a consignment
RQ =
x 100
where, Q = Quantity supplied Q1 = Quantity accepted Q2 = Quantity accepted with concession Q3 = Quantity accepted with rectification Q4 = Quantity rejected And Q = Q1 +Q2+Q3 -+Q4 X1 and X2 are weightage factors each less than 1.
6.
Expl Explai ain n how how wou would ld you you pro proce ceed ed in in desi design gnin ing g a was waste te dis dispo posa sall syst system em for for a ste steel el pla plant nt
Ans:
The adoptio adoption n of poor disposal disposal practic practices es have have resulted resulted in severe severe environme environmental ntal pollution pollution in different parts of the world, particularly in the big industrial centres and have posed serious threat to human life. Some of the developed countries have taken the problem on war footing and have starte started d develo developin ping g and adopti adopting ng latest latest technolo technology gy in this this regard regard.. In India India the awareness has grown recently and the design of effective waste disposal system has become a challenging problem area. From disposal viewpoint wastes may be categorised into: (i) Salvable waste and (ii) Non-salvable wa waste
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The waste that have got some salvage value are termed as salvable waste. The scrap, rejected goods, surplus/obsolete items and equipments etc., fall under this category. The well designed disposal system for salvable wastes may provides best return to the organisation; contribute to cost reduction and higher profit and aid to material conversation. Wastes which do not have any salvage value, but need further processing and treatment for disposal are termed as non-salvable non-salvable waste. The non-salvab non-salvable le wastes wastes may amount to resource resource recovery recovery and reduced environment and other social costs. Waste disposal system for a steel plant: plant: The salvage waste, e.g. scrap, surplus/obsolete stor stores es and and equip equipme ment nt is gene genera rate ted d in almo almost st all all sort sorts s of manu manufa fact ctur urin ing g and and serv servic ice e establishm establishments. ents. The steel plant waste is disposed disposed off through through auction. Another mode of dispos disposal al is to salvag salvage e scrap scrap throug through h specia specialis lised ed agenci agencies. es. A specia speciall surplu surplus s dispos disposal al committee was set up for analysing the large quantities of accumulated surplus. For disposal of steel plant scrap, a committee in consultation with Metal scrap trade Corporation and MMTC. Here Here some some broad broad guidel guideline ines s have have been been sugges suggested ted to aid the design design of syste systems ms and procedures for disposal of steel plant waste are as follows: (i) (i) (ii) (ii) (iii (iii)) (iv) (iv) (v) (v) (vi) (vi) (vii) (vii) (vii (viii) i) (ix) (ix)
(x) (x) (xi) (xi) (xii) (xii) (xiii) (xiii)
The The fea feasi sibi bili lity ty of recy recycl clin ing g sho shoul uld d be be ana analy lyse sed d to to dis dispo pose se the the scr scrap ap.. Try Try to to us use sc scrap rap for for pro produc ducing ing by by-pro -produ duc cts. ts. Try Try to to tra trans nsfe ferr the the surp surplu lus s fro from m one one plan plantt to to ano anoth ther er Anal Analys yse e the the feas feasib ibil ilit ity y to sel selll the the scra scrap p as raw raw mat mater eria iall to oth other er pla plant nts. s. Anal Analys yse e the the feas feasib ibili ility ty to to sell sell the the scr scrap ap/s /sur urpl plus us to to exte extern rnal al expo export rt age agenc ncie ies s dealing with it. Sell Sellin ing g the the scra scrap p thr throu ough gh adv adver erti tisi sing ng and and thr throu ough gh auct auctio ioni ning ng.. The auctio auction n shou should ld based based on the scrap scrap carryi carrying ng cost cost and auctio auction n cost cost.. The The surpl surplus us may may be sold sold to the the own comp compan any y emplo employe yees es or in the the open open market. If the the pro produ duct ct is is not not meet meetin ing g the the requ requir ired ed sta stand ndar ard, d, it sho shoul uld d be sold sold to company employees as secondary quality item. Which can give the incentive to the employees. To cons consul ultt the the vend vendor or and and ret retur urn n the the surp surplu lus s to to ven vendo dor. r. To sell sell surp surplu lus/ s/ob obso sole lete te equip equipme ment nt throu through gh adve advert rtis isem emen entt and and invi invite te the offers from other parties In case case of dam damage aged d equip equipme ment nt try try to sell sell after after the the part parts s afte afterr clas classif sifyin ying g into into good serviceable, repairable or reclaimable, and scrap. If the the scrap scrap is is usefu usefull for charit charitabl able e organi organisat sation ion,, it shou should ld be dona donated ted to to it.
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