Study on Improving the Production Rate by Rapier Looms in Textile Industry Aby Chummar, Soni Kuriakose, George Mathew

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1 Study on Improving the Production Rate by Rapier Looms in Textile Industry Aby Chummar, Soni Kuriakose, George Mathew Abstract In India the textile industry is growing very fast. Most of the earlier established textile industries are using conventional shuttle looms for the production of the cloth. But the advancement in the technology made the textile industry more competitive. The effective usage of the new methods of the weaving technology, which is more energy efficient, makes the production more economical. It is found out that the usage of the conventional looms badly affects the cloth production. This study focuses on identifying the problems associated with the low production by the shuttle loom and suggesting suitable methods by which these problems can be reduced. Index Terms Greige Fabric Picks, Rapier Loom, Shuttle Loom. I. INTRODUCTION The science of textiles predates recorded history. Archaeologists have found evidence that man has fabricated coarse cloth from various fibers for at least 20,000 years and intricate textiles have been found in tombs in Egypt and Asia that have been dated to several thousand years before Christ. Many of the processes which were developed in ancient times are still used in remote areas of the world today [1]. However, with the advent of the Industrial Age, rapid developments in machinery and textile manufacturing techniques have advanced the science of textiles more in the past one hundred years than in all of previous history [1]. Today's sophisticated CAD/CAM controlled machines result in high-speed, low-cost and large-volume textile production [1]. Looms are the important machines used for cloth production. The different looms used for the production of the cloth are shuttle looms, rapier looms, jet looms, etc. The power looms are used for weaving terry towels and bed sheets. Techniques used for the production process in the industry are Warping, Sizing, Beam Drawing, Weaving, Cutting, Un-winding, and checking in warehouse, Folding, Recounting, Grading and sorting, Bailing or packing [1]. The main energy forms used in a textile industry are grid electricity, wood, and small quantity of coal [5]. The electricity is used for power looms, doubling machines, winding machines, warping machines and lighting. Wood is used as fuel for boilers, thermic fluid heaters, and chulhas for hot water generation. II. PROBLEM DISCRIPTION A study on a garment industry was carried out in a leading garment manufacturing company in Kerala. The study mainly focused on 382 shuttle looms. Over the years, the company was involved in production of garments and Greige fabric. Greige fabric is one of the critical products manufactured in the company. It is mainly manufactured by the shuttle looms. Conventional shuttle looms are mainly used during the weaving process in the industry. All these shuttle looms are too old. In these present conventional shuttle looms, it is necessary to pass a shuttle weighing around half a kilogram through the warp shed to insert a length of weft yarn which weighs only few grams. The shuttle has to be accelerated rapidly at the starting of picking cycle and also to be decelerated, stopped abruptly at the opposite end. This process creates heavy noise and shock and consumes considerable energy. Beat-up is done by slay motion which again weighs a few hundred kilograms. The wear life of the picker and checking mechanism is also limited due to heavy shocks. The small weft package in the shuttle requires frequent replenishments and for each loom stoppage there is a possibility of one defect. Due to the defects in the looms the rate of production was reduced. Low speed of the loom is also a reason for the low production rate of the machine. The low speed of the machine increases the operating time there by increasing the consumption of electrical energy. So during the present global scenario of energy conservation, alternatives for the conventional methods have to be identified. Table I: Factors Affecting Low Production Rate and Their Percentage Factor Seconds affected (s) Percentage (%) Speed Yarn Break down Man Environment Total

2 Fig 1: Fish Bone Diagram For Low Production Rate III. METHODOLOGY In the study picks generated by randomly selected shuttle looms are analyzed. Each machine was observed for 600 seconds. The time taken for generating picks and the time during the stoppage of the loom is also noted. The noted time is classified into operating time and no operating time. In the operating time it was identified that the picks generated by the looms are lower than the ideal pick rate which is calculated using (1). The main causes for the low pick rate are identified by plotting the cause and effect diagram in fig 1. Fig 2: Pareto Chart For Low Production Rate When a problem occurs in a system, its causes should be identified for the problem to be fixed. Ishikawa Cause and Effect (CE) diagrams are popular tools to investigate and identify numerous different causes of a problem. A Cause and Effect (CE) diagram can be used as a guideline to allocate resources and make necessary investments to fix the problem [4]. The percentage by which each Factor affects the low production rate is shown in the Pareto chart in fig

3 Table II: Average Ideal Pick Rate for 1 Month SI No Month Days Total time Ideal pick rate R Ideal pick rate for 382 looms Ideal pick rate for 1 hour 1 Jan Feb Mar Apr May Jun July Total Average Table III: Average Actual Pick Rate SI no Month Actual pick Actual production time(hours) 1 Jan Feb Mar Apr May Jun July Total Average IV. RESULTS AND DISCUSSION Table V shows the distribution of cost for the production of 1 meter of cloth in the textile industry and it is also represented in the pie chart in fig 6. Yarn is important raw material used for the production of the greige fabric. The company cannot compromise the quality of the yarn used. The cost of yarn depends on the international market conditions. Thus it is difficult to reduce cost f fyarn. Thus for reducing the cost production the industry itself have to make necessary SI no Table IV: Energy Consumption of Machines Machine changes in their production strategy by identifying the major types losses and by suggesting necessary remedies for reducing it. Actual rate of production The production rate of the looms is analyzed by the picks generated by the looms. Ideally a pick is obtained by the loom when the shuttle moves from one beating arm to another. The actual picks generated by the machine for 7 months are obtained from the company log book and it is shown in the Energy consumption/hr (units) 1 Cimcco power loom

4 2 Sulzer loom Sizing,cooking,storage,boiler Pirn winding Humidification plant 21 5 Warping machine Bailing 15 8 Cone winding machine 3 9 Folding machine 2.2 Total Table III. The Actual Production Time For Generating Picks By 382 Shuttles Looms Also Shown In The Table III. Ideal rate of production Ideal pick rate is the number of picks that the machine is capable of finishing when the loom operates with full efficiency. The ideal pick rate is calculated by using (1). The speed of the machine is 140 rpm and the working hours per day are considered as 22 days. Ideal pick rate=speed time (1) The calculation of the ideal pick rate is shown in the Table II. There is a noticeable difference between the ideal picks and the actual picks generated. Ideal pick rate for 1 s = (8400/3600) = 2.33 Time for 1 pick motion = 1/ 2.33= 0.43 s Fig 4: Pareto Chart for Energy Consumption Table V: Factors Affecting Production Cost of 1 Meter of Cloth Si no Factor Cost % 1 Yarn 40 2 Energy 32 3 Employ 18 4 Others 10 Ideally for making picks the machine requires hours. But actually it takes hours. This is due to various losses arising from different regions of production. Thus the machine non-operating time is hours. The non-operating time is the time where the machine stops its production due to yarn breakage, pirn changing, machine failures etc. Thus the total production rate of the machines is reduced. The reasons for low production rate are shown in the fish bone diagram in figure 1. The details about the factors affecting low production rate and its percentage are shown in table I. Fig 2, the pareto chart shows that the low speed of the machine is the major factor affecting for the low production 110

5 rate of the machine. Because of the low speed of the machine the required production rate cannot be attained. The low speed of machine will increase the total production time followed by increase in cost of production. Out of the 600 seconds analyzed in different machines selected randomly, approximately 250 seconds are nonproductive time, and the remaining are productive time and the factors affecting the production of machine is shown in Table I. Due to the movement of the shuttle in the loom, smooth sequence of weaving is disturbed which affects the maximum running speed and hence machine production. The pareto chart for the energy consumption is shown in the fig 4. A 1HP motor is used for driving the shuttle looms. It is found out from the fig 4 that cimcco power loom consumes 66% of total energy consumption of the industry. The low speed of the machine is due to the age of the machines, working condition of the machines, and the increased weight of the shuttle in the machines. Because of the low speed of the machine the consumption of energy by the machine increases. The electrical energy consumption for the different machines in the industry is shown in the Table V. It is found that the energy consumed by the shuttle loom is higher than any other machine in the industry. The reduced speed of the machine will increase the time of production and the lead time of the product is also increased. So to maintain increased production the speed of the machines has to be increased. To increase the speed of the machine, an improved way of production has to be followed. This improvement can be attained by the replacement of the conventional shuttle looms by the Rapier looms. Proposed energy efficient equipment (Rapier looms) Description of equipment The rapier looms offer unparalleled versatility when it comes to yarns. From the finest counts of cotton to the thickest Industrial yarns and can handle anything thrown at its negative rapier head. The soft-pick gear system enables smooth transition of even highly fancy yarns like embroidery and slub. The rapier loom is upgrade from shuttle-looms to the world of modern weaving system and shuttle-less weaving. Rapier looms has been designed to replace the old shuttle looms without any major changes to the existing infrastructure [2][3][5][7]. The Immediate benefits of selecting rapier looms are [2][3][7] No need for new buildings or any new infrastructure. Could fit in place of your current shuttle-looms. Configured specially keeping in mind the skills of power-loom operators. No special training required for loom operators. Immediate reduction of man-power and laborers. 20% subsidy under Technology Up gradation Fund Scheme (TUFS) on certified looms. Fig 5: Cost of Factors Affecting Production of 1 Meter of Cloth in % Speed The normal speed of the conventional power looms is around 140 RPM, where as in rapier looms, the speeds up to 220 RPM (actual), this machine gives up to 3 times more productivity than the conventional power looms. Pick rate of rapier loom The speed of the rapier looms is 220 RPM. Thus the ideal pick rate of 1 rapier loom can be obtained using (1) as Fig 6: Reduction in the operating time So the time for 1 pick by the rapier loom can be reduced to 0.27 seconds from that of the conventional shuttle looms. Improvement in production rate The average picks generated by the conventional shuttle looms are For producing this much amount of picks the ideal time taken by the shuttle looms are hrs. The time for obtaining picks by the rapier looms is approximately Hrs. Thus by rapier loom the machine 111

6 operating time can be reduced to Hrs. Thus from the fig 6 it is clear that 37% reduction in the total operating time is obtained. When comparing with the shuttle loom 57.5% more pick is obtained by the rapier loom. Cost savings In Kerala the cost of one unit of electrical energy = 4 Energy consumed by 382 shuttle looms (1 hp motor) per hour = 382 kwh For the conventional looms total cost of energy consumed = Total energy consumed by the rapier looms = kwh The total cost of energy consumed by rapier looms = Thus by the rapier looms cost saving of can be obtained in one month from the electrical saving itself. V. CONCLUSION To exist in a competitive world of industries, producing products at a low price with good quality is necessary. Accepting new technology, the production cost can be reduced, at the same time the rate of production can be increased. This study identified the problem of high energy consumption of electricity by the usage of shuttle looms in a garment industry. It suggested a remedy of replacing the aged shuttle looms with the automatic rapier looms for increasing the rate of production, thereby reducing the time of operation of machine and reducing the total lead time in production. Thus cost of production can be reduced. By rectifying other reasons noted in the cause and effect diagram in Fig1 production rate can be again improved. Further studies on the rapier looms can be helpful for the multi color weft insertion which will increase the variety of product according to the fluctuation market conditions. REFERENCES [1] Ryuta Kamiya, Bryan A. Cheeseman, Peter Popper, Tsu-Wei Chou, Some recent advances in the fabrication and design of three-dimensional textile performs: a review Composites Science and Technology 60, 33-47, [2] Dr.V.M.Patil1, P.D.Bhanawat, Techno-economics & advances of shuttle-less weaving technology, IJSID, 2012, 2 (1), [3] Subhankar Maity, Kunal Singha, Mrinal Singha, Recent Developments in Rapier Weaving Machines in Textiles, American Journal of Systems Science 2012 ;( 7-16). [4] R. Ufuk Bilsel, Dennis K.J. Lin, Ishikawa Cause and Effect Diagrams Using capture Recapture Techniques, Quality Technology & Quantitative Management Vol. 9, No. 2, pp , [5] A. N. M. Masudur Rahman & Md. Ruhul Amin, Efficiency analysis in rapier loom (2000). [6] Bill Carreira Lean manufacturing that works. [7] Bureau of Energy Efficiency, Detailed Project Report on Auto Loom/Rapier Loom (2000). AUTHOR BIOGRAPHY Aby Chummar, Post Graduation Student, Dept. of Mechanical Engineering, Mar Athanasius College of Engineering, Kothamangalam, Kerala. Soni Kuriakose, Associate Professor, Dept. of Mechanical Engineering, Mar Athanasius College of Engineering, Kothamangalam, Kerala. George Mathew, Assistant Professor, Dept. of Mechanical Engineering, Mar Athanasius College of Engineering, Kothamangalam, Kerala. 112