STUDY AND MODIFICATION OF LINE ASSEMBLY TECHNIQUE FOR TATRA EQUIPMENT

Transcription

1 International Journal of Production Technology and Management (IJPTM) Volume 7, Issue, July-December, 016, pp , Article ID: IJPTM_07_0_00 Available onle at Journal Impact Factor (016): (Calculated by GISI) ISSN Prt: and ISSN Onle: IAEME Publication STUDY AND MODIFICATION OF LINE ASSEMBLY TECHNIQUE FOR TATRA EQUIPMENT Ravikumar Thonnur Siddaramu Graduate apprentice traee, B.E.M.L Earth movers Limited, Mysore , India Rakshith Subbaraju CNC Mache programmer, Geede Package Private Limited, Mysore , India Shaswath TD Associate Software Engeer, Tech Mahdra, Bangalore , India ABSTRACT Initially majority of the sub-assembly operations of TATRA equipment were beg carried out the ma le stead of performg some of the sub assembly activities parallel to the ma assembly le. This results are creased equipment assembly life cycle time. One more problem associated with the existg layout is that tools required for the entire assembly operation was placed at tool room which was very far from the workstation and the materials spare parts to be assembled was kept at stores which was also very far from the workstation. This makes the works to travel long distance whenever he needs tool or a material, resultg wastage of time.these problems were tried to overcome the proposed assembly le by shiftg some more assembly activities from ma le to the parallel le which resulted reduced equipment assembly life cycle time. In the proposed assembly le, ma le assembly activities are divided to different stages. Tools and assembly materials required for that particular stage activity is arranged near to that stage location or work station there by reducg the unnecessary movement of men and materials. Key words: Sub-Assembly-Ma assembly le-assembly life cycle time Cite this Article: Ravikumar Thonnur Siddaramu, Rakshith Subbaraju and Shaswath TD, Study and Modification of Le Assembly Technique for Tatra Equipment, International Journal of Production Technology and Management (IJPTM), 7(), 016, pp editor@iaeme.com

2 Ravikumar Thonnur Siddaramu, Rakshith Subbaraju and Shaswath TD 1. INTRODUCTION In order for any company to meet the demands of the customer it should produce a large variety of products and at the same time it should perform the production operations at the mimum possible time order to get advantage over its competitors. So the reduction the production time is the major concern for any company. In order to do that well planned plant layout, storage space, material handlg and le balancg are crucial. The existg assembly operations of TATRA 6*6 trucks are carryout le production. It means operations are carried out le and also number of several operations are added a parallel le to the ma le dependg on the requirement. Ma aim of this research is to reduce the cycle time of the assembly operation of TATRA 6*6 equipment by conductg study of assembly operation of the truck and makg some modifications the assembly le. In the existg assembly le there are total seventeen assembly operations, which corporates fourteen operations ma le and only three assembly operations parallel le. So, order to decrease the assembly cycle time 5 operations are shifted parallel to the ma le activities thereby reducg the assembly cycle time.. METHODOLOGY.1 Plant layout Plant layout embraces the physical arrangement of dustrial facilities, this arrangement either stalled or plan, cludes the spaces needed for material movement, storage and all other supportg activities or services, as well as for operatg equipment and personnel. The plant layout means the disposition of the various facilities (equipment, material, manpower, etc.) and services of the plant with the area of the selected previously. Many appear to believe that the layout should be developed first and then material handlg system should be developed yet material handlg decisions can have a significant impact on the effectiveness of the layout. Material handlg Startg from the time, the raw materials enters the factory gate and goes out of the factory gate the form of fished products, at is handled at all stages between, no matter it is the stores or on the shop floor. It has been estimated that average material handlg cost is roughly 0-60% of the total production cost and the ratio between the weight of the handled material to produce an item and weight of the fished item may vary between A component may be handled even 50 times or more before it changes to fished product. Material handlg volves the movements of materials, manually or mechanically batches or one item at a time with the plant the movement may be horizontal, vertical or the combation of horizontal and vertical..3 Storage space requirements Adequate storage space allocation to different materials and supplies is of great importance because otherwise, a small crease their quantities may give rise to congestion and the whole system may be out of gear. The followg items and amount of stock holdg determe the storage space requirements. 1. Incomg new materials editor@iaeme.com

3 Study and Modification of Le Assembly Technique for Tatra Equipment. Checkg and sortg of new material before it is placed at the proper location. 3. Inspection of raw material. 4. Temporarily storg sortg, the new material before it is placed at the proper location. 5. In-process ventory 6. Tools and other supplies 7. Fished products..4 Le assembly An arrangement of workers, maches and equipment which the product beg assembled passes consecutively from operation to operation until completed. Also called production le. An assembly le is a manufacturg process which terchangeable parts are added to a product a sequential manner to create a fished product. Production method requirg workers to perform a repetitive task on a product as it moves along a conveyor belt or track. An assembly le has the advantages of part standardization and rationalization of work. An assembly le is designed by determed the sequences of operations for manufacture of each component as well as the fal product. Each movement of material is made as simple and short as possible, with no cross flow or backtrackg. Work assignments, numbers of maches and production rates are programmed so that all operations performed along the le are compatible..5 Assembly le balancg An assembly le may be thought of as a series of assembly stations through which a product must pass an orderly, established sequence. A well planned and stalled assembly le mimizes the processg time without violatg the product requirement. The assembly process can be broken at a given location performg specified tasks. Each of these tasks adds value to the fal product. However, the tasks must assign to the various work stations accordg to the precedence requirements so that the idle time over the whole process is mimum. An ideal situation would volve a le which all the stations would have equal work content, measured terms of time, assigned to them. In this ideal case perfect balance would exist, but this seldom happens practical situation. Complicated tasks may be subdivided to smaller units of work called elements. Consider the assembly of a unit made up of ten components. One element of this assembly operation would be to pick up one component and place it on another. It is assumed that the time required to perform each element can be reliably estimated by observation, and that time to perform each element is dependent of the arrangement of the elements. Two approaches to the assembly le balancg problems have been used. 1. Fixed production rate to optimize the number of stations. Fixed work stations to mimize the cycle time. 3. RESULTS AND DISCUSSION 3.1 Present le assembly technique The time and men required for each sub-assembly operations the present le assembly technique is as shown the Table 1. The existg assembly le of TATRA 11 editor@iaeme.com

4 Ravikumar Thonnur Siddaramu, Rakshith Subbaraju and Shaswath TD 6*6 trucks is basically a le production. The time consumed the ma le is not affected by the time consumed by the parallel le. The entire assembly process consists of totally seventeen operations, which corporates fourteen operations ma le such as Backbone assembly, Axle preparation, Air system assembly, Frame mountg, Frame electrical, Enge mountg, cab mountg, Airtake and exhaust manifold assembly, Air cleaner assembly, Servo steerg circuit and air duct Cab electrical and chassis electrical, equipment start and wheel mountg, CQA test, Platform mountg and Fal testg, and remag three parallel le such asplatform furnishg,frame furnishg, Suspension sub-assembly. Sce majority of the sub assembly operations are performed the ma le it results creased assembly life cycle time, more congested work stations, and creased waitg time of semi-fished product. Fally, all these thgs lead to reduced productivity. Table 1 Time and men required for each sub-assembly operation for existg assembly le of TATRA 6*6 equipment is as shown the above table Ma le sub assembly operations Time Parallel le Sub-assembly operations time hours Back bone assembly 13:00 5 4:36 Air system 89:00 4 :5 Frame mountg 4:00 1:00 Frame electrical 45:00 :30 Frame furnishg 71:00 3 5:39 Enge mountg, cab mountg and air take assembly Servo steerg circuit, air system and air take manifold Cab electrical lamps 91:00 4 :45 50:00 5:00 Suspension subassembly 50:00 5:00 Equipment start and wheel mountg 48:00 4:00 49:00 4:30 CQA test 53:00 6:30 Platform mountg and fal testg 53:00 6:30 Platform furnishg 51:00 5:30 Total result 596: :6 5: :59 The time and men required for the dividual assembly operation mentioned each and every operation. Where is the standard man hour which specifies the 1 editor@iaeme.com

5 Study and Modification of Le Assembly Technique for Tatra Equipment standard time required by one worker to perform that particular assembly operation and cycle time specifies the time required by total number of men that particular work station. For the entire assembly process the required is 81:00 Hrs. In the existg layout the time consumed the ma le is 39:6 Hrs which is the equipment assembly life cycle time. Equipment assembly life cycle time is obtaed by addg up the cycle time of each assembly operation. So the time required for the complete assembly of sgle equipment is 39:6 Hrs which is equal to 9.9 days (39.6/8hrs per shift). In other words, it takes 9.9 days for a truck to get transformed from back bone stage to a fished product stage. The total waitg time of semi-fished product is 5:50 Hrs. 3. Problems identified From the study of assembly technique of TATRA 6*6 equipment BEMEL, the problems noticed were, 1. Increased assembly life cycle time.. More pots of congestions and confusions. 3. Increased waitg time of semi-fished assembled parts. 4. Improper storage of tools and materials. 5. Reduced productivity. 6. Improper way of le balancg. 7. Shortage of raw materials. 8. Little scope for Material handlg improvement. 3.3 Proposed assembly technique The time and men required for each sub-assembly operations the present le assembly technique is as shown the Table.After noticg the problems associated with the existg assembly le some of the changes have been made the assembly le to overcome those problems. Changes made the assembly le are: 1. Three of the sub-assembly operations from the ma le such as frame electrical, cab electrical & lamps and platform furnishg are shifted to the parallel le, which reduces the assembly life cycle time of the ma le. This may reduce the congestion and confusion pots.. Sub-assembly operations the ma le have been divided to five different stages. By makg such division, tools and materials required by that particular stage could be placed nearer to that stage by makg use of racks, which reduces the movements of the workers. 3. Reallocatg the standard man hour required by sub-assembly operations based on the difficulty of the job. 4. Table :Time and men required for each sub-assembly operation for proposed assembly le of TATRA 6*6 equipment is as shown the above table 13 editor@iaeme.com

6 Ravikumar Thonnur Siddaramu, Rakshith Subbaraju and Shaswath TD Table Time and men required for each sub-assembly operation for proposed assembly le of TATRA 6*6 equipment is as shown the above table Stages time Parallel activity time Stage :36 Backbone Assembly Axle preparation Stage :00 Air system Stage 3 Frame mountg 45 :45 Frame electrical 45 :30 Frame furnishg :30 Stage 4 1.Enge mountg, cab mountg.air-take assembly 3.Servo steerg circuit, Cab air system, cab air take 4.Equipment start and wheel mountg :45 :30 1:30 Cab electrical and lamps Suspension sub assembly, Tire embrose, frame grase 48 4: :00 Stage 5 1.CQA test 46 3:00 Platform mountg 70 3 :30.Platform mountg 48 4:00 Total : : Outcomes of the changes made the assembly le. Equipment assembly life cycle have been reduced from 39:6 Hrs to 184:11 Hrs. Which implies that the time consumed the ma le have been reduced by 55:15 Hrs (which is equal to 6.8 days). 1. From the division of sub-assembly processes to five different stages the tools and materials required by the particular stage is placed very nearer to it. This reduces the distance moved by worker to get a tool or a material.. Material handlg gets reduced. 3. Waitg time of semi-fished product have been reduced from 5:30 Hrs to :45 Hrs editor@iaeme.com

7 Study and Modification of Le Assembly Technique for Tatra Equipment 4. CONCLUSION In the existg layout the movements of workers and materials were more, so the proposed assembly le by the division of sub-assembly process to five different stages the tools and materials required by the particular stage is placed very nearer to it. This reduces the distance moved by worker to get tools or materials. The materials required for the particular stage have been placed near to the work station usg racks the assembly le. Two of the sub-assembly activities of the male have been shifted to the parallel le the proposed assembly le thereby reducg the assembly life cycle time. In the existg assembly le the assembly life cycle time required by the ma le was 39:6 Hrs and there was a waitg time of around 5:30 Hrs. By shiftg the zone of the sub-assembly operations from the ma le to parallel le we could be able to reduce the time consumed the ma le to 184:11 Hrs which implies that the time consumed the ma le have been reduced by 55:15 Hrs (which is equal to 68 days) and by applyg the le balancg technique we could reduce the waitg time of semi-fished product from 5:30 Hrs to :45 Hrs. REFERENCES [1] Plant layout and material handlg by JAMES M APPLE [] Facilities planng by Titomics [3] Plant layout design by James M Moore [4] Production and operations management by Chary [5] Material management and tegrated approach by Gopal krishna P and M Sundareshan [6] Practical plant layout by Muther Richard [7] Nannikar Amolraj A, Malgave Sujit. S, Patil Dhiraj D, Bhore Harshal. S and Wadkar Vivek V., Pneumatic Equipment Mass Production System for Grdg, International Journal of Production Technology and Management (IJPTM), 6(), 015, pp editor@iaeme.com