Wednesday, March 11, 2015

Project Report On Maynard's Operational Sequence Technique

INTRODUCTION

The manager or a small team of managers devotes thinking and energy to the various issues involved in improving productivity. In addition they must deal the problems of running of an enterprise at the same time. The main function of management has been recognized as “plan, provide and control” the “resources” necessary to achieve the desired results. Out of all resources human resources is the most difficult to control. Main stumbling block has been quantification of work- how much time to accomplish on given task. There have been many attempts to device a scientific method applicable over a large range of activities and be simple enough to be used by any one.



In engineering industry the first serious efforts were those of F.W.Taylor, refined over the years by many practitioners. New methods were searched when stopwatch studies revealed their limitations. Most of “predetermined time “systems were evolved. Some had limited applications and some had almost universal applications- MTM, work factor, clerical work measurement etc. was meant for universal applications. 

Each system had its own philosophy of looking at work, work content and work element. In this series MOST is the latest addition with its own philosophy.  

WORK STUDY
                 
          METHOD STUDY            WORK MEASUREMENT
       To simplify the job and          To determine how long 
       develop more economical                 it should take to carry out.
       methods of doing it.

PARTITION OF WORK STUDY

WORK- STUDY

Work study consists of two complementary techniques –method study and work measurement. Method study is the principle technique for reducing the work involved, primarily by eliminating unnecessary movement on the part of material or operatives and by substituting good methods for poor ones. Work measurement is concerned with investigation, reducing and subsequently eliminating ineffective time, that is time during which no effective work is being performed, whatever the cause.

WORK MEASUREMENT

The desire to know that how long it should to take to perform work must surely have been present in those individuals responsible for erecting ancient measurements of shaping tools. Why did the ancient and why do we need tobe able to predict with accuracy the length of working cycle? How was such a prediction made? How is it made now?

There are many reasons for wanting to know the amount of time a particular task should take to accomplish. It may simply be for reasons of curiosity but, realistically it is for any of the three reasons:
  • To accomplish planning
  • Determine performance
  • Establish cost.
Suppose an organisation wishes to manufacture a new product. Using a economical, pre- determined motion time system, the planning and budging process could be accomplish. Knowing the time to manufacture and assemble various parts and / or components, a manager could:
  • Determine the total labour cost of the product
  • Determine the no. of production workers needed.
  • Determine the no. of machines needed.
  • Determine the amount of and delivery times for material.
  • Determine the overall production schedule.
  • Determine the feasibility of entering in to production of the product.
  • Set production goals.
  • Follow- up on production: have goals been achieved?
  • Check individual or departmental efficiency.
  • Know t he actual cost of production. 
  • Pay by results.
As a consequence a manager can achieve an even and sufficiently high utilization of personal, material and equipment to result in an overall efficiency that will allow an organisation to survive and grow.

It must be assumed that the original form of work measurement was guessing. It is interesting to note that a primitive guessing technique employed thousands of years ago is still in use today in many modern manufacturing organisations. Today’s version is a much advanced form of original technique, however, and is known as educated guess. The educated guess is unscientifically supported by intuition, individual personal experience, the importance of estimation to be made and the inherent ability or inability of the application to make a confident sounding response. Obviously this technique is not scientific (well  documented or statically supported) and not accurate ( with any degree of confidence or consistency.), but it is fast.

Once products began to be manufactured or work tasks completed, another source of information was available from which future times could be estimated. The historical data concept of work measurement evolve from records of what had been accomplish came the information for predicting times for future situations. Using historical data does one think very well, it accurately tells you what has already happened? To use it to predict what will happen assumes two major points:
  • The conditions and actions under which process was performing originally are what you wish to repeat (the best way of performing a task).
  • The actions to be performed will be performed exactly as those on which the historical data based.
PREDERMINED TIME STANDARDS

A predetermined time standards is a work measurement technique whereby times establish for basic human motions (classified according to the nature of the motion and the conditions under which it is made) are used to build up the time for a job at a defined level of performance. By ILO there are a more than 200 PTS in the world. We can find the origins in the 1920’s F. G. Gilbreth, A. Segur, H.B. Maynard and many others contributed something to the development of PTS: therbligs, wofac, MTA, MTM and so on. However, generally work measurements specialist accept Methods Time. Measurement (MTM) as basis of measurement or use the motion patterns based on MTM as a backup data for other PTS.

In analysing any kind of manual task, it is possible to break that task into a series of movements, such as reaching, grasping, and carrying, among others. Researchers have been able to develop standards time for each of these basic movements. By breaking any task into the appropriate basic movements, it is possible to develop a standard time for the entire task by adding of the standard times for each individual movement. This approach is especially useful in developing times standards for a new job that has not yet been implemented. Because predetermined times standards are based on thousands of observation made under controlled conditions, individual workers are not being timed, and there is less room for disagreement about the results. For these reasons, quite a few companies used predetermined standards, although the stopwatch time study approach is still more common.

ACCURACY OF PMTS

This technique (MTM) is not appropriate for SME that produce in lower volumes. This productivity of the work analyst is very low. He is able to analyse only several minutes (two, three, ---) taking operation for one shift in accordance with the detailed constructions of MTM. It insures high accuracy but on the other side low productivity we can ask. How accurate do we have to measure work? Machinist work in thousandth millimeters, sometimes in millimeters. Carpenter accuracy is expressed in several centimetres or millimetres. Why are there so relative high deviations in accuracy? And what about the work analyst? Should operation time be accurate within thousand of seconds, or would plus or minus one day be acceptable. Obviously, both these conditions are in appropriate. 

The answer is that the accuracy of PTS must be considered in terms of cost involved to achieve certain level of accuracy. More exact times require more detailed analyses and more time for making it. It is necessary to consider what is cost for analyses and on the other side what are economical benefits that can be released for detailed analyses. The development of more productive systems has been continuous since the development of MTM. The majority of these systems are based on the combination of basic motion patterns to new merged motion.

 For example in the system MTM 2 the three basic motions (reach, grasped release) are merged to the new motion get. Further, two motions (move and position) are merged to new motion put and so on. The work analyst must consider several variables. Also during analysis, some motion is some times omitted from motion patters or erroneously included. This applicator errors occurs relative often when we use these systems. Errors depend largely on the level of applicator experience.
 Then we have a very accuracy PTS (system error is very low) but the overall accuracy of the analyse will be lower as we assume by applicator deviations.

CONCEPT OF MOST

DEFINATION OF TERMS
        
  In order to facilitate the understanding of the following text for the reader, the definition of several terms commonly used in connection with MOST systems will be presented here.
  • Operation
  • Sub-operation
  • Time standard
  • Activity
  • Method step
  • Sequence model
  • Sub activity
  • Parameter
  • MOST analysis
Since the logical result of work measurement tast is to establish a time standard for an operation, let us first define the term operation.

OPERATION
An operation is (1) a job or task consisting of one or more work elements, usually done essentially in one location;(2) the performance of any planned work or method associated with individual, machine, process, department or inspection or;(3) one or more element that involve one of the following; the intentional changing of an object in any of its physical or chemical characteristics, the assembly or disassembly of parts or objects; the preparation of an object for another operation, transportation or inspection or storage ; planning calculation or giving or receiving information.

Both the work measurement and standard setting procedure can be simplified and made more efficient through the use of fractions of operations called sub operations. The definition of sub operation is as follows:

SUBOPERATION

A sub operation is a discrete, logical and measurable part of an operation. The content of such sub operation may vary depending on type of operation, accuracy requirement and application area. Two or more sub operation may be combined into a combined sub operation.

TIME STANDARD

A time standard is the total allowed time including manual time, process time and allowances that it should take to perform a task to perform a task or do a job. An engineered time standard is the time it should take to perform a job based on established and documented work condition and specified work methods. (The pure operation time without allowance is called “normal” time)

ACTIVITY
An activity is here defined as a series of logical events that take place when an object is moved, observed or treated by hand, a tool or a transportation device. An activity starts when an operation leaves his or normal location (workplace) to perform these events and concludes when the operator has returned to the original or release the object. The work activity also may be used in general sense designing a task or a series of events.

METHOD STEP

A method step is a descriptive formulation of an activity. One or more (usually 5-20) method steps organized in sequence according to the applied method will constitute an operation or sub0operation.


SEQUENCE MODEL

 A sequence model is multicharater representation of a single activity. One sequence model is applied to each method step. Several predefined sequence models represent different types of activities.

SUBACTIVITY

 A sub activity is defined as discrete subdivision of an activity or sequence model.

PARAMETER
 A parameter is a one-character representation of a sub activity.


MOST MEASUREMENT SYSTEM

Work is displacement of a mass or object. This definition applies quite well to the largest portion of work accomplished everyday, like pushing a pencil, lifting a heavy box, or moving controls on a machine. All basic units of work are organized (or should be) for the purpose of accomplishing some useful results by simply moving objects. That is what work is. MOST is the system to measure work, therefore, MOST concentrates on movement of objects. MOST is based on different investigation of movements. It was noticed that the movement of object follows certain consistently repeating patterns, such as reach, grasp, move and position the object. These patterns were identified and arranged as sequence of events (or sub-activities) manifesting the movement of object. A model of these sequences is made and acts as a standard guide in analyzing the movement of object. It was noted that the actual motion contents of the sub activities in that sequence vary impendent of one another.

This concept provides basis of MOST sequence models. The primary work units are no longer basis motions as in MTM but are fundamental activities (collections of basic motions) dealing with moving objects. These activities described in terms of sub activities fixed in sequence. In other words, to move an object, a standard sequence of events occur. Consequently, the basic pattern of object’s movement is described by a universal sequence model instead of an aggregate of detailed basic motion.

 Objects can be moved in only one or two ways: either they are picked up and moved freely through space, or they are moved in contact with another surface. For each type of move, a different of sequence of events occurs; therefore, a separate MOST activity sequence model applies. The use of tools is analyzed through a sequence model which, infact, is a combination of the two basic sequence models.

MOST SYSTEM FAMILY

Most is used to economically measure work from the building of ships and railed car to minute electronic assembly and rapid-pace yarn-handling operations.
There most system family is as follows
  • Basic MOST
  • Mini MOST
  • Maxi MOST
  • Clerical MOST
Basic MOST is routinely used to analyze the very wide range of manual operation most common to industry. Mini MOST provided detailed analysis of highly repetitive operation such as small assembly and packing of small items. Clerical MOST, an extension of Basic MOST is used for analysing office activity. Maxi MOST is used for longer cycle operation, such as setups, maintenance, material handling, heavy assembly and job shop work. Let us study Basic MOST in detail.

THE BASIC MOST MEASUREMENT TECHNIQUE

BASIC MOST

At the intermediate level, operations that are likely to be performed more than 150 but fewer than 1500 times per week should be analyzed with Basic MOST. An operation in this category may range from a few seconds to 10 minutes in length. (Operations longer than 10 minutes may be analyzed with Basic MOST, with 0.5 to 3 minutes being typical cycle time for Basic MOST). The majority of operations in most industries fall into this category. Basic MOST index ranges readily accommodate the cycle-to-cycle variation typical at this level. The method descriptions that result from Basic MOST analysis are sufficiently detailed for use as operator instructions.

Consequently, only three-activity sequences are needed for describing manual work. The basic MOST work measurement technique is comprised of the following sequence models:

  • The general move sequence-for the spatial movement of an object freely through air.
  • The controlled move sequence-for the movement of an object when it remains in contact with a surface or is attached to another object during the movement.
  • The tool use sequence- for the use of common use tools.
  • The forth crane sequence model-the manual crane sequence for the measurement of moving heavy objects by using, for instance, a jib crane, is also part of basic MOST system, although used less frequently than the first three.

GENERAL MOVE SEQUENCE MODEL

It is defined as moving object manually from one location to another freely through the air. It is most commonly used sequence model. Roughly 50% of all manual work occurs as a General move. The activity sequence is made up of four sub-activities as shown in figure.
E.g. Walk three steps to pick up the bolt from floor level, arise and place the bolt in the hole.

CONTROLLED MOVE SEQUENCE MODEL

This sequence is used to cover such activities as operating a lever or crank, activating a button or switch or simply sliding an object over a surface. As many as one-third of the activities occurring in machine shop operation may involve controlled moves. In assembly work this type of motion required.
E.g. Engaging of the feed lever on the milling machine.

TOOL USE SEQUENCE MODEL

This sequence covers the use of tools for activities like fastening or loosening, cutting cleaning, gauging etc. this sequence is a combination of General move and Controlled move activities. It was developed as apart of the Basic MOST systems merely to simplify the analysis of activities related to the use of hand tools.
E .g. Tightening of screw with screwdriver.

The above sequence model are made up of sub-activities (series of parameters organised in a logical sequence).
The sequence model defines the events or actions that always take place in a prescribe order when an object is moved from one location to another. The sub activities or sequence model parameters are then assigned with time related index numbers based on the motion content of the sub activity. This approach provides complete flexibility within the overall control of the sequence model. For each object moved, any combination of motion might occur, and using MOST any combination be analyzed. The index values are easily memorized from a brief data card. A fully indexed sequence model might appear as follows

A0 B6 G1 A1 B0 P3 A0


Where

A0= Walk 3 to 4 steps to object location

B6= Bend and arise

G1= Gain control of one light object

A1= Move object a distance within reach

B0= No body motion  

P3= Place and adjust object

A0= No return

TIME UNITS

The units used in MOST are identical to those used in the basic MTM (Method – Time Measurement) system and are based on hours and parts of hours called Time Measurement Units (TMU). The following conversion table is as follows:

1 TMU = 0.00001 hour
1 TMU = 0.0006 minute
1 TMU = 0.036 second
1 hour = 100,000 TMU
1 minute = 1,667 TMU
1 second = 27.8 TMU

The time value in TMU for each sequence model is calculated by adding the index numbers and multiplying the sum by 10. In our previous example, the would be 

A0 B6 G1 A1 B0 P3 A0
          
          ( 0     +   6    +   1    +   1   +    0   +   3    +    0 )    X   10 = 110 TMU

SEQUENCE MODEL COMPRISING OF BASIC MOST WORK MEASUREMENT TECHNIQUE

CALCULATIONS

EXAMPLE : Get a handful of washers and p-lace on 6 bolts located 12 cm. apart.

A1 B0 G3 (A1 B0 P1) A0 (6)

A1=Reach to washers

GET B0=No body motion

G3=Collect handful of washers 

A1=Reach to place washers
PUT B0=No body Motion

P1=Place washer, loose fit 

RETURN A0=NO Return

The time calculations are as follows:
1) (A1   B0 P1) = (1+0+1)
2) 2 X 6 = 12
3) 1+0+3+12+0 = 16
4) 16 X 10 = 160 TMU

MOST –ANALYSIS

A MOST analysis is a complete study of an operation or a sub operation consisting of one or several method steps and corresponding sequence model as well as appropriate parameter time values and total normal time for the operation or sub operation (excluding allowances). It has been developed based on experience. It can be used to determine how long it takes an operator to perform an operation on a machine or how long it takes to assemble any given product. It is a relatively simple method of synthetic time setting where one hour of work takes approximately 20 hours to  describe, compared to the methods MTM -1 and MTM-2 where the description of an hour of work takes approximately 350 and 175 hours, respectively. The MOST –analysis is reliable method –which is widely used in the industry.

York Casket Case Study

Maynard Gets Results:  Maynard Helps York Casket Think Outside the Box.

The York Group is the second largest manufacturer of caskets in America, and is a leading manufacturing of all-wood caskets. Founded in 1892, the company was purchased in 2001 by Pittsburgh-based Matthews International Corporation, a leading manufacturer of memorials. York manufactures wood caskets in York, PA.

Like many manufacturers, York faces an increasingly competitive marketplace. To meet this competitive challenge, Matthews’s corporate management has challenged York to significantly improve division profitability.

For York to remain competitive and meet Matthews’s operating objectives, division management needed to reduce unit costs by 20 to 40 percent. To reach this goal, York partnered with H.B.Maynard and Company, Inc. for assistance in converting the wood casket plant to a Lean Continuous Flow operation.

“Given the scope of the project, I knew Maynard had the deep bench we would need to complete it quickly,” said Ron Cameron, York’s Director of Manufacturing.” They had the right depth of resources and expertise to assist us.”

With input from corporate management, York managers set goals for the Lean initiative which include:
  • Reducing direct labour unit costs by 20 percent or more
  • Cutting production response time in half
  • Reducing inventory costs and product handling damage
  • Improving plant space utilization
  • Building a continuous improvement culture
The ultimate goal was to increase profitability while improving quality,” Cameron said “We knew we had to make changes, or the business wouldn't be able to move forward.

Early in the planning process, York management agreed on key Principles to help set vision for their Lean conversion, and the future operating strategy for the plant. York’s key principles are:
  • Committed leadership
  • Continuous flow production
  • Quality built-in
  • Safe, orderly and clean workplace
  • Flexible cross-trained team
  • Visual workplace
  • Standard work methods
  • Continuous improvement
These principles were posted in conspicuous locations throughout the plant, and reviewed with supervisors and employees in a variety of settings. The intent was to begin to establish the operational culture for future plant operations.

York Gets the MOST out of Lean, by Design
The strategy recommended by Maynard was to first design a Lean Manufacturing system using sound industrial engineering tools, including value –stream analysis, work method design and work balancing using engineered time standard, and kanban –controlled work flow. This approach, in contrast to Kaizen events, would predictable, sustainable results.

To improve the operation presented various of challenges. A “push “ production system would need to be converted to “pull”. Standard, documental work methods would be required. Continuous work flow and extensive worker cross –training were needed .Ultimately, a complete; change would be required in every one’s approach to their job from the hourly worker to the plant management.

“Maynard helped us move from batch to continuous flow,” Cameron said, 
“We established the vision for continuous flow through first studying how we work and then engineering new method to improve both product quality and productivity.” The tear decided that the best place to begin the Lean conversion was closest to the customer, the casket team area. Like the rest of the plant, this area suffered from many typical ailments of a non –Lean operation, including product quality problems, inconsistent work methods, bath production, excessive inventory and extensive non –value added work.

The York and Maynard team began by reviewing work methods and work flow in three ----- the plant’s casket team processes, the team could identify variations in how the work was being performed, and develop Best Methods. Using the Maynard Operation Sequence Technique (MOSTR), the new methods were measured and standard times determined. An improved work flow could then being designed.

For example, the plant’s trim department previously workstations located over a large area, with inconsistent workplace layouts. To correct this problem, the team first determined the best methods and standard times to complete the work. With this information, trim assembly line was designed to replace the individual trim benches.
In the hardware area, parts were spread over a large area, requiring workers to take unnecessary stapes to retrieve parts. In addition, hardware assembly was located away from the main production line, furthering inefficiency. The hardware area was redesigned to directly feed parts to the production line.

In the interior sew department, the old batch process caused inefficient part flow, as parts were placed in the casket and then transported to the trim bench. Like the hardware department, Interior sew was not integrated into the main production line. Best Methods and standards were developing to better balance the work. To establish continuous flow, the line loading rules, kanbans and visual signals were designed. Their layout was redesigned for integration on to the main production line. 


Making the Move

With the design complete, team began to prepare for the “big move”. Revised layout was developed using computer aided design. Puzzles peaces were used to brainstorm the best way to plot the new plant layout.

Prior to the move, the plant floor was marketed with new equipment location. All equipment required for the new layout was identified and coded on the CAD layout and the plant floor. Where required, material storage devices were purchased or build prior the move. The layout was reviewed with all the employees, and they were given the opportunity to provide additional input on the work station design.
 
The team work together for develop a system for the move, using many 5 –S principle 5 –S helps to create LEAN environment that is clean, orderly and safe, while opening the company culture to change and installing new disciplined. Motivated employees to embrace culture of change figured to challenge, as York’s employees average one year of experience. But Cameron noted that the changes were received favourably by employees because of involvement and the focus on creating an improved workplace. “The key was communicating to employees as often as possible” Cameron said. “It was important to get their feedback and empower them to create better ways to perform the work. We also use incentives, such as providing rewards for suggestions, which helps to motivate employees further.” 

York Reaches Goals

This initiative provided an immediate impact on York’s productivity. Shortly after implementing the changes, York saw a 20% reduction in labour hours per casket the post finish area. Defects were reduced by 48%.
Production response time in the post finish area was reduced dramatically from three hours to one hour. In turn the value added ratio increased from 19% to 50%. And with it work piece now turn in to continuous improvement, York expects future productivity gains.

The key differentiator or between the Maynard approach the typical to search is the application of industrial engineering tools and design. With this truly engineer approach, the best solution is arrived at early, and trial error is minimized.
    
The casket trim area is the first of four major project phases. Results in the second phase (casket assembly) promise to be even better than the first.” Sew and trim had already been improved by a lean project, so these results are even more impressive,” Cameron noted. “Now, thanks to Maynard’s help, we’ve been able to become even leaner. It was a great effort, and we expect it to pay off for many years to come.”


ADVANTAGES OF MOST
The MOST has a family of tools. By means of these we can economically measure work dependent on type of activities (building of ships, electronic assembly,--).Basic MOST is used to analyse the very wide range of manual operation most common to industry. Mini MOST provides detailed analysis of highly repetitive operations (electronic assembly) and Maxi MOST is used for longer cycle operations. Clerical MOST and extension of Basic MOST, is used for analysing office activities. For selecting the appropriate MOST Work Measurement System we use a simple procedure.
MOST was designed to be much faster than other work measurements technique, as is shown in fig.

COMPARSON OF APPLICATION SPEED 

Thus the advantages are as follows:

  • Universal approach
  •  Fast to apply
  • Accurate 
  • Easy to understand and learn 
  •  Multi –level system 
  • Consistent results 
  • Encourages method development and improvement 
  • 100% performance level 
  • Methods sensitive Activity timings can be obtained in advanced


APPLICATIONS
  • Assembly 
  • Metal working
  • Electronics
  • Aerospace
  • Material handling
  • Textile
  • Ship building
  • Maintenance
  • Utilities
  • Administration
  • Hospitals
CONCLUSION

In the end I conclude MOST guarantees the overall accuracy of the final time standard. It dramatically decreases applicator deviations through pre printed sequence models. During the analysis procedure, the applicator attention is focused on each sequence model parameter as calculation sheet is failed out. Also it solves problems with documentation. The more detailed system, for example, requires 8 to 20 times more pages of documentation.

MOST Computer System is designed to assist the industrial engineer to become more productive on the job. It is based on the concept keywords that represent type of grasping, movement, and positioning the sequence. It enables grater speed, does standard calculation, sets and maintains completely labour time.  

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