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TPM Implementation through small groups for zero defect production of parts
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TPM Implementation through small groups for zero defect production of partsAuthor : Vinod Kumar Singh, Ordnance Factory Board, Kolkata, INDIA ABSTRACTTotal Preventive Maintenance (TPM) is a shop floor management technique developed more precisely by JIPM and is focused about developing autonomous small groups of operators. It concentrates on increasing the robustness of production process by focusing on process plant and human resources around it. It believes in increasing the participation of workers and systematically developing there knowledge about the processes they are handling. The paper describes the methodology of implementing TPM, advantages of TPM in PM industry and continuous improvements resulting in Zero Defect Production of existing products and then developing a capability to develop new products with Zero Defect. Key Words: TPM, Manager Machine Model, Autonomous Maintenance, Zero Defect, Hygiene factors INTRODUCTIONOrdnance Factory Board (OFB) under the aegis of Ministry of Defence, Government of India has mandate to produce conventional weapon systems and equipment to meet the need of armed forces. Heavy Alloy Penetrator Project is a facility established under OFB. HAPP is an ISO9001:2000 certified installation with Quality Control Laboratories at HAPP certified to ISO17025:1999. In order to provide superior product at least cost through enhance productivity HAPP had opted for operating in TPM (Total Productive Maintenance) environment as introduced by Japan Institute of Plant Management with required modifications to suit the working environment in a typically administered departmental production unit under Government of India. The TPM approach is primarily based on the philosophy of providing equipment and process knowledge to the operators and motivating to function in autonomous manner. TPM approach as suggested by JIPM1 was not suitable for operating in the Government sector production facilities. Modifications were necessary to suit the local conditions for suggested steps of JIPM TPM implementation methodology. HAPP has been divided into four production sections for maintaining the technology orientation. These are Powder Metallurgy (PM) Shop, Machine Shop, Surface Treatment Shop and Assembly Shop. A Divisional Officer or Head of Section commands each shop. Basic unit is controlled by a Charge-man reporting to Head of Section. Factory has 85 small groups of 5-8 workers and forms the basic unit. TPM implementation was extended to complete plant. PM shop is now successfully operating in TPM environment. PM shop in the plant is having 12 autonomous small groups. This paper describes the journey of implementing TPM in PM plant and the transformation of working environment to a new environment full with confidence and enabling culture. WHAT IS TPMTPM expanded by JIPM as Total Productive Maintenance starts with concentration on Maintenance of plant and Machinery. It is a union of systematic small group activity aimed at improving the system by concentrating on hardware, equipment, people and preventive maintenance aspects in a proactive manner. It starts with increasing the understanding of operators in the equipment and systematically developing them into change agents with a clear goal in mind to reduce the losses. Literally word TPM meant Total Productive Maintenance and concentrated on increasing Original Equipment Effectiveness (OEE) through autonomous small groups using 8 pillar approach and 12 steps suggested by Japan Institute Plant Maintenance(JIPM1). JIPM suggests implementation of TPM through Manager Machine Model to be practiced by CEO of the plant and carrying out the seven steps of Autonomous Maintenance. Eight Pillars started initially are Education and Training, SHE (Safety, Hygiene and Environment), Autonomous Maintenance, Planned Maintenance, Zero Defect, Initial Production & Flow Control, Continuous Improvement and Office Improvement. Technology and Energy committee were added later. In TPM operators and other workers form small groups that carry out knowledge sharing to increase the group capability. Groups have multi group activity to understand the requirements of customer group precisely and also interact with supplier groups to precisely demand what shall improve their performance. Groups determine their Productivity, Quality, Delivery, Safety and Motivation targets. TPM AT HAPP PM PLANTTo implement TPM, management selects a model machine and starts implementing 7 steps of autonomous maintenance (AM) activities. In PM plant Cold Isostatic Plant (CIP) was selected as manager machine model and the author being the officer in-charge of PM Plant Operations undertook the exercise of implementing seven steps. At the same time all the workers and middle management personnel were given training in the concepts of TPM and AM. Author followed a half an hour schedule once a day cleaning the plant and identifying the counter measures to be taken to reduce the cleaning requirement. Oil and powder leakage points were fixed and the plant design was modified to completely plug the areas from where the powder use to come out in the environment while being filled in the mould bags and while being transferred from Double Cone Blender to CIP hopper. All hydraulic Oil pipes were replaced with steel pipes and white paint was applied at the joints to ensure that any leakage is visible immediately. It was noticed here that plant down time reduced and breakdowns vanished. Production Operators were initially spectator later formed a group with author and started helping improvement activities and within fifteen days they took over the actual ground execution operations. Next step was to prepare Lubrication and Inspection Standards by identifying the points where lubrication need to be checked and the points where regular inspection be carried out to ensure that plant functioned smoothly. Thus a Cleaning, Lubrication & Inspection Standard was generated. At this stage author while working with the model group initiated group formation in the other work centers of the plant. Soon the workers seeing the model group formed small groups with specific focus on mixing & compaction, sintering, vacuum heat treatment, swaging, post swage machining and testing area. Middle management cadre gladly joined the groups along with the workers. As a first step all the group members were given extensive training about the plant they are using while implementing first step of AM activity which involves cleaning the plant thoroughly and systematically all the groups generated Cleaning Lubrication and Inspection Standards. During cleaning emphasis was laid that the person doing the cleaning understands why he was required to clean those areas, how did the imperfections, which necessitated cleaning, affected the performance of plant in terms of output quality or performance. What can affect the safety, quality, maintainability and reliability of equipment Groups then identified the Countermeasures to be taken to ensure that daily cleaning of plant and equipment is not at all required and the plant is being maintained into as cleaned level without routine daily cleaning. Operators while performing AM learnt what to inspect in a routine manner on the plant. Identify the items that should be checked regularly and fixed. Determine lubrication needs of the plant - type, frequency and amount of lubricant. Group prepared a standard schedule for cleaning, inspection, lubrication with the help of plant maintenance manual and maintenance personal. Operators followed standard schedule for each machine, plant and furnace for 3 months and again revision was done to change frequency, delete redundant items to decrease the time spent in following the standard. In the event of any breakdown or quality problem this standard was revised based upon a Why -Why Analysis of failure and eliminating the root cause. Sequence of Goals was fixed as Zero accident, Zero Grievances, Zero Defect, Zero Breakdown, and there after constant reduction in losses in terms of material and energy by identifying the component of material and energy which was not being directly carried away by product. After about 12 – 18 months it was seen that small groups started functioning in normal manner and breakdowns vanished. Quality of product also stabilized and batch failures and quality variations vanished. It was also noted that TPM group activities had increased workers confidence to a very high extent. Persons who were earlier resistant to any change were now suggesting changes themselves regularly and were taking active part in implementing the change. Another benefit was now they were taking more interest in analyzing the process and were experimenting to improve the same. Cost of production went down as a result of continuous improvements being undertaken by groups. It was seen that TPM implementation approach advocated by JIPM proved to be the fastest and most accepted by employees. GROUP MANAGEMENT STRUCTUREManagement through groups is the basic philosophy of TPM. TPM aims at creating group, training the group to manage themselves in autonomous manner. Groups of an area make a group of group leaders. Divisional Officer of the shop is the leader of group of group leaders. Secretary of subcommittees are member of leader groups. CEO is the Chairman of Group at plant level. Secretaries and Chairman of all committees, administrative heads of shop level group are members of this group. Each group sends a member to participate in a sub-committee as a representative of group. This group meets once a month to review the performance of the shop and coordinate TPM activities in the shop. Group orientation has the advantage that any individual is not put to hardship, as he cannot be relieved to meet emergent necessities whenever they are required for official work. It has a disadvantage that certain persons may feel that they are losing their importance. This feeling, in any case, has been found to be of very temporary nature and as in a group the leader, always is a person with higher knowledge and experience the individual ego gets satisfied. It is also noted that the leader is supported by the knowledge and experience of other members in a group in a synergetic manner. In TPM we revolutionize the working so that the best part of every individual is extracted and distributed to other members of group, thus building a group-strength. Divisional Officer is chairman of all subcommittees in the shop also leads the controlling group. He maintains group focus to organizational goal. Divisional Officer sends a weekly report to TPM coordinator on a pre-designed format. He also schedules all intra-shop and inter-shop group meets. He ensures that group meetings are held regularly and the improvements identified by the group are implemented in time in a economical manner. He is required to find problems in group-growth in a proactive manner and encourage the group activity. He helps group to identify targets and helps them achieving the same. He leads and manages people, groups, and subcommittees in a networked manner. He has specific attention on pushing CI projects to conclusion. Group relationship is shown in the figure below:
Group activities have grown with time and the customer and supplier relationship is established among the groups in the PM plant. Sintering group is customer of compaction group and powder-mixing group is supplier for compaction group. Vacuum Heat treatment, is customer of sintering group and acts as a supplier to Pre swage machining group. Swaging group is customer of pre-swage machining group and supplies to finish machining group. The ultimate customer is testing and inspection group. This group interacts with the external customers in this case machine shop. Groups assign specific responsibility to individual members for a specific pillar activity. Generally this member represents group in the subcommittee meetings for that pillar. This arrangement offers a distinct advantage that almost every member in the group is leading a certain activity in the group and all members are interdependent for their image outside the group. PILLAR AND COMMITTEESPillar is a specific area of strength to be extended to all groups in a coordinated manner. In TPM, At plant level a committee is formed for systematic furtherance of activities with reference to this strength throughout the plant. For each pillar activity there is a subcommittee in each work area. Subcommittees have their members drawn from groups in the shop. Officer in charge of the shop identifies one person from these to be the secretary of subcommittee for the shop. Secretaries are generally person who have demonstrated active interest in the particular strength and have recognition from the group. Secretaries of Subcommittees are given very specific focused training in this field and act as a referral person to all the groups in their area. Plant level committee has all secretaries of sub committee as its member and a senior officer having committed and demonstrated capability as chairman of committee. He/She is a person who has received specific training on the strength identified by the pillar. For example, Chairman of energy committee shall be a top level executive who has experience in managing energy, understand energy audit, has knowledge about new products in the global market and has interest in constantly upgrading his knowledge in that field. It is desirable that Chairman of subcommittee should attend some meetings of committee to keep himself aware of the developments. Committee meetings are held once in two weeks. Committee reviews all the activities being done in different sections and helps in identifying and providing external inputs. It also monitors that training section conducts focused program to train the operators in a particular area. They help in providing the training material and resource person. Pre determined Formats to be used by section subcommittee and groups for displaying their information are finalized by committee. It helps standardization. Committees also identify the projects/improvements to be horizontally deployed throughout the plant. Subcommittees in a shop meet weekly and list down all the activities identified in a shop. They coordinate resources required to carry out a kaizen, condition monitoring, inter group meetings and keeping of records in a shop. They help group to identify target in the area and horizontal dissemination of knowledge and experiences across the groups. They liaison with outside agencies and arrange external resources required by the group. Every Subcommittee prepares a brief in a pre- determined format and submits it to the secretary of committee and TPM coordinator. They carry out horizontal deployment of improvement projects identified in Committee in the shop through groups. Brief account of different committees are given below: AUTONOMOUS MAINTENANCE COMMITTEEAutonomous Maintenance (AM) is the most fundamental and prime activity in TPM. AM Committee systematically monitors implementation of seven steps as suggested by JIPM throughout the plant. Identifying the targets for each shop and training needs of groups for autonomous maintenance is major job of the AM committee. The committee to control the design of equipment to facilitate autonomous maintenance does interaction with new equipment suppliers. Identification of Innovative AM ideas and their horizontal deployment throughout the plant is another major task of committee. Success of committee is reflected in achievement of Zero Breakdown and Zero Accident. Identification of hygiene factors and their uprooting is also a specific goal of this committee. Committee ensures that through Autonomous check sheets and Cleaning, Lubrication, Inspection and fixing standards all such factors that contribute to fluctuation in quality are uprooted. CONTINUAL IMPROVEMENT COMMITTEEContinual improvement (CI) as a result of group effort is the essence of TPM. Increasing worker participation in the improvement is mandate of this committee. To ensure that CI projects (Kaizens) progress in a smooth manner is the mandate of committee. Groups identify CI projects and register these with the committee. Horizontal deployment of the successful CI projects is a major responsibility of CI committee. CI committee arranges resource requirement of special nature. EDUCATION AND TRAINING COMMITTEEEducation and Training Committee runs training department of Plant and arranges basic training of all employees in the basic concepts of TPM and AM. It has a mandate of raising skill level of all workers in a systematic manner to convert them from sedentary worker to knowledge worker. Identification of Master Trainers, preparation of one-point lessons, providing educational facilities to all employees to further their carriers in the organization are its major mandates. The committee undertakes preparation of training program for new technology being introduced. ENERGY COMMITTEEEnergy Committee analyzes the energy input into product through groups. It has a constant job of identifying potential improvements to reduce energy input in process operations. It scans improved devices and plans systematic up-gradation of plant, machinery and practices. It has a mandate to increase energy consciousness of all employees. Efforts of committee resulted in reduction of Maximum Demand from 3.5MW to 2.8MW. Increasing use of solar energy and other green sources is another major agenda for future. Generation of hydrogen by solar cells is identified as most promising. INITIAL FLOW CONTROL COMMITTEEInitial Flow Control Committee ensures that all the processes are well defined and documented. It defines the route a new product shall take. Groups to be involved in the development of a new product. Tooling, Fixtures, Gauges, Storage and Handling requirements for a new product are deliberated in Initial flow control committee. Product Design and Development group of the plant functions in close coordination with the committee. Chief Design Manager of the plant is generally designated as the chairman of the committee. It works in close coordination with all shops. Its mandate is First Time Right through process approach. OFFICE MAINTENANCE COMMITTEEOffice Maintenance Committee keeps all outward correspondence and papers related to personnel matters, purchase, accounting and audit requirements in a structured manner. This reviews all systems and progressively plans for filing and documentation in a manner that all documents can be retrieved for reference without delay, any external query can be handled in less than ten minutes. Any reference by any worker for his requirement is made available immediately. Things are kept in a defined regimented manner using 5S. Office Management Committee has taken up systematic computerization of process data, maintenance of archives for old drawings & specifications, project management internal and external transactions. The aim is to do it in a manner that the information is available for reference by all levels through an interactive screen. PREVENTIVE MAINTENANCE COMMITTEEPreventive Maintenance Committee is the main stay to start TPM operations and in making TPM implementation successful. PM committee monitors that Preventive Maintenance program are implemented for all plant and machineries in the unit. With continuing training of operators about plant and process and progress of steps of AM the PM program is gradually reduced. PM Committee plans this change in a very systematic manner by providing necessary skill training and support for special tool requirements to groups. PM Committee also monitors the expenditure on maintenance, spares and initiates kaizen for improvement of spare life thus constantly increasing mean time between failures (MTBF). Once step 6 of AM has been implemented on the equipment, it takes action to ensure that required spares are scheduled properly. Condition Monitoring program to ensure that time based PM schedules are changed to condition based proactive maintenance schedules, is introduced by PM Committee. Consumption of lubrication oil and other consumables in maintenance is monitored over a period and PM Committee ensures its availability. SAFETY, HYGIENE AND ENVIRONMENT COMMITTEESafety, Hygiene and Environment Committee ensures that there is no accident in the operations being carried out. A specially trained officer in safety matters chairs it. They systematically monitor activities to remove causes of accident. Groups to ensure operational safety critically analyze all operations. CI projects are taken to modify plant design to ensure zero accident probability. Check points are also identified and introduced in the AM sheet to ensure that all critical points are monitored periodically. Adherence to Statutory requirements and industry standards like ISO14000 is the minimum standard to which committee targets initially and goes much beyond. TECHNOLOGY COMMITTEETechnology Committee develops process and plant to meet specified needs. It has specific focus on different technologies available globally. Committee reviews the developments in related fields and takes strategic decision to acquire or evolve the technology for adaptation. As committee has links down to the worker groups, adaptation of any new technology is very quick and benefits can be harnessed with least lead-time. This committee decides the manner of acquisition or development of technology. Persons at all levels are pre-specified and do participate in negotiations and planning. A check on acquisition process by groups ensures that no minor detail is overlook at any time and the speed of acquisition is well adjusted. ZERO DEFECT COMMITTEEZero Defect Committee has mandate that in a production process no defective is produced. Monitoring customer complaints and refining of process, material specifications, quality maintenance and assurances activities are reviewed by the committee. Identification of technology factors and hygiene factors and providing necessary inputs to keep them under check so that no defective is produced is basic job of the committee. It monitors the cost of quality and plans to reduce the same in a continual manner. To update quality matrix, root cause analysis whenever a defective is produced is major effort taken by the committee. Mistake proofing of production line to ensure that no defective moves to next stage is major exercise taken by committee members throughout the plant. Identification of data storage and processing requirements, training of person in QC and QA techniques with emphasis on implementation in the area of work, reducing the customer complaint and process rejection to zero are the targets pursued by committee. Monitoring of quality CI projects and their horizontal integration is the prime responsibility of committee members. Organizing Supplier-Customer Group meets and resolving the issues generated there in, ensuring that development process has visible quality assurance system and any error is prevented from occurrence in a pre-defined manner are the activities undertaken by committee. Committee also pursues preparation of single point lessons on quality matters. Committee also monitors the use of Analysis tools where Zero Rejection targets have not been achieved. Vendor education on matters of quality is also done by this committee. MANAGING MEETINGSAt this stage one will have a feeling that executive and staff in the plant will be always be busy in organizing the meetings and many of these meetings will be very prolonged affair. But it is not so. Initially the meetings are in a haphazard manner but soon these become very systematic. Each meeting is kept limited to 30 minutes. First five minutes are spent to review developments of previous period, next twenty minutes are devoted on specific business of the day and last five minutes to record decisions, responsibilities and targets for next period. Every participant in the meeting presents his view in Transparent Open and in Totality (TOT). It is seen meetings reach to the TOT state in six months generally. Minutes of meetings are made available in few minutes and delivered electronically. Minutes also serve as information sheet during the next period under review. The first line management uses minutes as review sheet. All developments are recoded on these sheets. In the next meeting the sheet is available with updated details and new ideas or projects for a quick reference and discussion. Meeting is also an informal forum to teach all the formalized procedure being evolved. Development of group is the essence. If the volume of work increases in a particular area, frequency of meeting was increased to daily with invitation to other supporting group leaders to be available during the meeting. Later this was changed to supply the inputs during the first five minutes of meeting schedule telephonically or through mail to secretary/chairman prior to start of the meeting. Expectations from other groups are communicated at the end of meeting. On the subjects of mutual interest multi group meetings are organized. CI projects often require multi-group participation. Committee and subcommittee have a distinct role to play in multi-group working. ACTIVITY BOARDEvery group has prepared an activity board. This board displays photographs of conditions of plant and machinery and shop floor before and after implementation of seven steps of AM. Targets of the group, CI projects under implementation and Single point lessons are displayed on this board. A look at the board gives a clear picture of the road map of group for next six months. All past achievements are displayed on the activity board and constantly motivate group members and other groups. Biggest advantage is that during visits of customers and discussions no preparation is needed. It also develops group creativity and ability. Display Boards are focal center for group weekly activity. Format is predefined and flexible and is determined by group by discussions with customer groups and Divisional Officer. ONE/SINGLE POINT LESSONSOne point lesson is a major tool for transferring the knowledge from expert to others. One point lesson is prepared in the form of a chart and teaches a single activity. Names of person who can be classified as expert are mentioned in the chart. Expert are given specific time at their disposal to teach others. More and more persons acquiring skill to master’s level are developed. Once a person acquires skill equivalent to master his name is also entered in the chart. Group leader and member responsible for Education and training of group systematically monitor acquiring of skill. He ensures that all persons in the group acquire at least two skills and develop proficiency to master level. In TPM one point lesson is systematic way of disseminating skill across the plant. PM plant developed Single point lessons for Relation of Microstructure with sintering cycle variation, Effect of Annealing on quality, Effect of Die alignment on swaging, CIP cycle, density measurement etc are prepared for penetrator bar. It is also ensured that all members are attempting to acquire higher education qualification in the field of their interest. TPM NEWSLETTERAfter reaching a stage TPM newsletter is started. Generally this stage is reached with two to three years. Frequency of newsletter in starting is monthly and then increased to weekly. It is basic mass communication device. Targets and Achievements, Plant policy, Area of Thrust, Message from CEO, Exemplary CI projects, Status of AM achieved in different shops, persons upgraded to masters, New One point lessons, Future training program are announced through TPM Newsletter. It replaces routine circulars. Committee Activity during previous period is an integral part of Newsletter. Plan is to introduce an evening channel to increase the efforts in this direction. INFORMATION MANAGEMENT IN TPMSuccess of TPM in a plant depends on speedy solutions to problems identified by small groups and thus leading the small group by example. Intra and inter group information exchange in TPM is key to success. There is a necessity to communicate the customer feedbacks to each group. Information management in TPM is done through display boards. Each group maintains a display board. In this board, targets and achievements against each pillar activity is displayed and is updated at the end of day by a designated member of the group. One-point lessons are very important piece of information on the board. Production scheduling, drawings and process capability is displayed on each plant and machine. Targets, Achievements and action plans are displayed with the road map. It will look as a very dedicated Information Management team is necessary for all these activities, but it is not so, this is a result of daily group meeting. Where on a pre-designed format the information are updated as a matter of routine in a playful relaxed environment. Divisional officers or charge-man based upon his discretion made ERP system available accessible to select groups, which have achieved a degree of autonomous working. This motivated other groups to pursue their sincere efforts for achieving a level of autonomous working. A LAN is planned to increase the speed and reduce use of paper. RESULTS OF TPMAll out improvement was noticed in the plant as a result of implementing TPM. Cost of product dropped to 50% of original. Stage and Batch rejections became nil. Energy input per job was reduced to 60%. Maintenance Expenditure for plant and machinery came down to 10% of original. It was noticed that all workers have acquired creative skill and were more interested in developing new products in their area once they acquired Zero defect and breakdown. Some took part in developing control alogrithum, while other started concentrating in increasing degree of automation. Many groups in PM plant started surfing internet and started taking keen interest in development of new products. DIVERSIFICATION IN TAPs AND OTHER TUNGSTEN BASED ALLOY PRODUCTSTPM Efforts made it possible to plan for diversification in the plant. Improved working permitted management to think beyond routine. Experimental facilities for Mechanical Alloying were added. A planetary mill and hydraulic press was installed with a meager investment of about US$8000. Worker-groups developed Oscillating Blanks of Watch, Balancing Weight Blanks for Chetak Helicopter, Balance Weight for Inertial Navigation System for Missiles, Thrust Plate for Trishul Missile, Boring bars for Sandvik India Ltd., Tungsten Copper Electrodes, Inserts for frangible bullets, Tungsten weight balancing granules for Advanced Light Helicopter etc. IMPORTANCE OF MAN & MAN MANAGEMENTMost important factor in PM plant is man, most vital link between various operations and subsystems. Defining training requirements, career progression, motivational schemes, psychological needs of the employees need to be studied and monitored and given careful implementation. Any problem in industrial relations can have very high cost and should be settled in a proactive manner before seeds of unrest are laid. Managing the process of HRD through groups avoids grievances. Each person has a full knowledge of the capability of others and is able to appreciate the contribution individual can make to the total effort. Group is able to select right men for the right job and is able to implement corrections almost instantaneously. They are able to groom employees in a informal environment. PM personnel need to be controlled through mind, heart and soul to make them fully engrossed in his work when he is on job. Training costs of each employee involved in PM installation is likely to be in the range of Rs.4 to 5 Lakhs (US$10000) and its gain are made very effective using small group philosophy in TPM. Managers will have to keep a watch and use innovative methods to keep employee turnover in control. They have to plan a systematic changeover program. HRD is a very key concern in developing enabling environment and should be handled by the Top Management as a group concern. Every technical manager and Group Leader should also be trained in basic HRD principles. One Hour training to every employee per week was done through in house resources. CONCLUSIONTPM methodology propagated by Japan Institute of Plant Management is a very effective strategy for starting group working and making them autonomous. Such Group work is key to unleash the creativity of persons and drives the cost of product to minimum. It is best to convert a line organization into matrix organization. New expansion for TPM was defined by workers in the PM plant as TOTALLY PERFECT MANAGEMENT. ACKNOWLEDGEMENTAuthor is thankful to Officers, Staff and Employees of PM Plant, HAPP, Chairman O F Board and Ministry of Defence for extending their support, all family members, and colleagues for their untiring efforts and help in implementing the TPM methods. REFERENCES
PRESENTED AT PMAI 2005 MUMBAI ON 4.2.2005
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