A Study on the Quality Control System Andres Andrea Printing Services Submitted by: Adrian Chester R. Inojales Chloie Nicole Sy Submitted to: Elaine P. Quinto In partial fulfillment of the requirements in Industrial Quality Control B.S. Industrial Engineering Ateneo de Davao University 1st Semester, 2018-2019 1 Table of Contents Background................................................................................................................................ 3 Scope and Limitations ................................................................................................................ 4 Assumptions .............................................................................................................................. 4 Objectives .................................................................................................................................. 4 Definition of Terms ..................................................................................................................... 4 Methodology .............................................................................................................................. 7 Data Gathering........................................................................................................................... 7 Analytical Tools .......................................................................................................................... 7 Findings ..................................................................................................................................... 8 Data Analysis ............................................................................................................................. 9 Recommendation ......................................................................................................................11 Appendix A (Industrial Quality Control Checklist) ......................................................................15 Appendix B (Documentation) ....................................................................................................16 2 Background Andres Andrea Printing Services is a printing shop located at Bolton St., Villa Fontana, fronting University of Mindanao Bolton Campus, Davao City. The printing shop caters a lot services including but not limited to t-shirt printing, sublimation printing, jersey making, uniforms and other garments. They also make personalized keychains, drawstring, bagtags, lanyards, etc. They started their textile and printing business in 2003. They have started their first branch in Obrero, Davao City where they cater clients mostly coming from University of Southeastern Philippines. They had very few competitors that’s why business was good for them during that time. They almost get 100% mark-up for every garment they sell. However, as the time passes by and due to inflation, they only get a small percentage for each product they make. One of their latest technologies today is the dye-sublimation printing. Dye-sublimation printing is where the printer uses heat to transfer dye onto materials such as a plastic, card, paper, or fabric. As what we have researched, the sublimation name was first applied because the dye was considered to make the transition between the solid and gas states without going through a liquid stage. This understanding of the process was later shown to be incorrect. There is some liquifying of the dye. Since then, the process is sometimes known as dye-diffusion, though this has not eliminated the original name. Dye-sublimation printing is a digital printing technology using full color artwork that works with polyester and polymer-coated substrates. Also referred to as digital sublimation, the process is commonly used for decorating apparel, signs and banners, as well as novelty items such as cell phone covers, plaques, coffee mugs, and other items with sublimation-friendly surfaces. The process uses the science of sublimation, in which heat and pressure are applied to a solid, turning it into a gas through an endothermic reaction without passing through the liquid phase. It has been used for long in other countries but was only introduced in the Philippines around 2008. In Davao, it was only introduced in 2015 and Andres Andrea Printing Services was one of the pioneers for this kind of printing. According to Ma’am Marlyn Alegarbes, the wife of the owner, told us that the reason that they have acquired a large sublimation printer is that most of their clients demand for more unique prints that ordinary printers can’t create. As of today, they are already 15 years in the business and they cater a lot of customers from different schools, organizations, and offices. They also have bigger cleints outside Davao. 3 Scope and Limitations The study is concentrated on the process of Sublimation Printing and its’ products from receiving of orders to the final product. Its main focus is the quality of the product through the present operations. More importantly, the study considered which quality characteristics (the hue of the print, the interweaving of the cuts, the cutting, and proper measurements) should be monitored to set standards for accepted and rejected outputs. Assumptions The production starts 10 am the earliest and ends 6 pm (though there’s are overtime periods up to 11 pm). One worker is assigned to recreate the design and operate the printer, another worker is for the heat press, and another is the seamstress. Orders are varying but on average they receive 60 orders of jerseys, warmers, or shirts. Compensation o Printer Operator- Minimum Wage (per week) o Heat Press Operator – P3/shirt o Seamstress – 30% of the set price per piece Objectives The objective of the study is to create a quality control system for Andres Andrea that will help them monitor the quality of their outputs. Definition of Terms Sublimation Printing - is a digital printing technology using full color artwork that works with polyester and polymer-coated substrates. Also referred to as digital sublimation, the process is commonly used for decorating apparel, signs and banners, as well as novelty items such as cell phone covers, plaques, coffee mugs, and other items with sublimationfriendly surfaces. Canvass - works as the paper of the sublimation printer. However, the canvass is in rolls and usually the grammage is up to 100 gsm to support the large format. Heat Press - refers to the merging of the canvass and the dri-fit cloth (a kind of sports cloth that resembles a silk, and lightweight) through the machine after its name. 4 Present Operations Process Flow for Sublimation Printing Process Owner Remarks Manager The manager will receive the orders since he also manages the front desk. Manager The customer can either choose to pay in full or pay the down-payment. Scheduling Manager Both parties will set a date that’s favorable for both. Purchase of raw materials (e.g. dri-fit textile, CMYK ink) Manager The manager will place their orders of raw materials to their suppliers. Manager/Available Workers Workers will check if the materials delivered by the supplier have any defects. Graphic Artist The worker will develop the design based on the customer’s preference and adjust it accordingly. Start Receives orders from customer Payment/Down payment Inspect the materials Process design on computer NO Does the customer approve of the design? This means that the customer checks the design if it meets their specifications and requirements. 5 YES Adjust the design according to the size of the canvass Transfer the design to a Large Format Printer via flash drive Print the design on the canvass Transfer pre-finished canvass to the sublimation printer Heat press the design and the drifit cloth together Graphic Artist The worker will adjust the size and position of the design to the necessary specifications for printing. Shirt Printer Shirt Printer Shirt Printer Shirt Printer This process will only take a couple of minutes. Cut the pressed cloth depending on the pattern Available Worker Sew the pieces together Seamstress Parts of the shirt (i.e. sleeves, neckline, cuff, placket, etc.) will be sewn together by the seamstress. Manager Check if the transfer on the shirt didn’t leave blotches or other marks. Inspect the shirt 6 Packing Completion of payment (if down payment) Manager/Available Workers Any worker available will help with the packing. Manager Pick-up or deliver the shirts Manager Customers will pick up their ordered shirts from the store. Methodology Data Gathering Information needed was gathered through conducting an interview with the proprietors, Mr. Darwin and Mrs. Marlyn Alegarbes, and also the workers under the sublimation process (the one who supervises the print, the one who does the heat press, and the tailors). Actual observation of the entire production was also conducted to gain further understanding of the process sublimation printing. Analytical Tools Analytical tools used to aid the analysts in gathering the data are the following: Industrial Quality Control Checklist- to breakdown and easily pinpoint the problems and issues needed to be resolved. Control Charts for Attributes- to help analyze and set standards for rejected and accepted lot. These tools would best meet the needs of the analysts in gathering information for the study. 7 Findings The data gathered below are past clients of the Andres Andrea Printing Services that have ordered materials sublimation print style. The data also provides information on the finish date, quantity of orders, type of product done in sublimation style, and the defects. There are only 15 orders noted in this data from late May to early October. They have only acquired the sublimation printing machine last May. Client SIMCARRD Team Royal Lion Advincula Law Office Brokenshire College St. John Paul II College University of Immaculate Concepcion Association of Barangay Captains College of Accountancy- UM Yuda Dust Kabacan Airsoft Team SEA-AdDU (Sublimation Jersey) Dream Vapor Body Wish (Massage and Spa) DC Invest EASEC AdDU Subli Print Date of Finish 10/1/2018 9/27/2018 9/19/2018 9/19/2018 9/13/2018 9/6/2018 9/2/2018 9/17/2018 8/12/2018 8/11/2018 8/2/2018 7/30/2018 7/21/2018 7/11/2018 5/26/2018 Type of Product T-Shirt Sports Uniform Sports Uniform Sports Uniform Sports Uniform Sports Uniform Sports Uniform Sports Uniform Sports Uniform Sports Uniform Sports Uniform Sports Uniform Sports Uniform Sports Uniform T-Shirt Quantity 50 80 20 32 36 90 45 54 23 45 90 20 18 200 32 Defects 1 3 1 0 1 10 0 2 0 3 6 2 1 5 1 P 0.020 0.038 0.050 0.000 0.028 0.111 0.000 0.037 0.000 0.067 0.067 0.100 0.056 0.025 0.031 Table 1.0 Sublimation Prints Data A defect can be defined as “a departure of a quality characteristic from its intended level or state that occurs with a severity sufficient to cause an associated product or service not to satisfy intended normal, or reasonably foreseeable, usage requirements” (ASQC, 1983, p.l3). The defects in the sublimation printing can be classified as follows; Improper Stitching – is the incorrect way of sewing the material as well as missed or skipped stiches resulting to holes. Heat Pressing Issues – such as crooked placement of the material which can result to folds and can cause white spots in the finished product, as well as color variance. Wrong information- such as wrong jersey number, misspelled names etc. 8 Data Analysis When the use of linear measurements in not practical, then attributes are often counted and appropriate charts constructed. Some of the more common attribute control charts are number of defects per sample (c charts), number of defects per unit (u charts), and percentage defective charts (p charts.). (Aft, 2009). In this case, defects are caused by human errors like the improper stitching the seamstress, the wrong information edited by the graphic artist, and the accidental folds on the heat press. The proponents see that the use of p-chart is appropriate in this circumstance. The percentage defective or proportion defective classification is used in cases where an item, after inspection, is classified as either acceptable or unacceptable. The percentage defective, p, is the number of defective units in a sample of size n, divided by the sample size. The average percentage defective, p, is the sum of the total number of defectives divided by the total sample size (Aft, 2009). To compute for the p’ p defectives p' items .inspected To compute for the upper control limit: UCLp = p’ + 3 p To compute for the lower control limit: LCLp = p’ - 3 p Computing for the p p' (1 p' ) n 9 The results of the formulas are as follows: Total Quantity Total Defective p' 745 26 0.0349 0.00672 Upper Control Limit 0.05507 Lower Control Limit -0.1585 Table 2.0 Calculations of UCL and LCL Client Defective Errors/Product SIMCARRD Quantity 50 1 0.020 Team Royal Lion 80 3 0.038 Advincula Law Office 20 1 0.050 Brokenshire College 32 0 0.000 St. John Paul II College Association of Barangay Captains College of AccountancyUM Yuda Dust Kabacan Airsoft Team SEA-AdDU (Sublimation Jersey) Dream Vapor Body Wish (Massage and Spa) DC Invest EASEC AdDU Subli Print 36 1 0.028 45 0 54 23 45 Mean 0.04311 0.04311 0.04311 0.04311 0.04311 UCL LCL 0.0551 0.0551 0.0551 0.0551 0.0551 0 0 0 0 0 0.000 0.04311 0.0551 0 2 0 3 0.037 0.000 0.067 0.04311 0.0551 0.04311 0.0551 0.04311 0.0551 0 0 0 90 20 6 2 0.067 0.100 0.04311 0.0551 0.04311 0.0551 0 0 18 200 32 1 5 1 0.056 0.025 0.031 0.04311 0.0551 0.04311 0.0551 0.04311 0.0551 0 0 0 As per calculation, the total defects are 26 in total quantity of 745. The UCL and LCL for the p-chart of the 13 batches of T-shirts and sportswear of Andres Andrea are 0.0551 and 0 respectively. Therefore, the recommended defective per batch must not exceed greater than the formulated UCL which is 0.0551. this will help company monitor their defects within the range of the control limits. 10 ANDRES ANDREA P-CHART p Mean UCL LCL 0,120 0,100 0,080 0,060 0,040 0,020 0,000 Table 3.0 Control Chart for Andres Andrea Printing The table above is a control chart for the month May to October of 2018 of which the company has accepted orders for sublimation printing presented with the following computations of the UCL and LCL. In the table, It is shown that orders from Kabacan Airsoft Team, SEA ADDU and Dream Vapor have exceed the upper control limit. Through this control chart Andres Andrea Printing can understand the importance of quality control in which they can see whether they are under their control as well as easily identifying and monitoring the defects per order. Recommendation The proponents suggest that Andres Andrea Printing Services should use p-chart as a tool for monitoring quality in their sublimation print products. The company can use the table below to be guided in setting up their quality control. In this table, they can really see what defects can they really look into. They can do this monthly or quarterly or whenever they find it convenient. It can also be suggested that they do Process Control Chart per defect so that they can analyze which defects occur mostly. 11 Order Client Quantity White No. Discontinuous/ Wrong Spot Unclean s Sewing Info Color Others Variation from Design 1 ABC - - - - Company Table 4.0 Blank Chart for Tallying Defects By identifying and counting the number of defects, the management can use Pareto Analysis in order to determine which defective category should they focus more their attention. Pareto Analysis is a simple technique for prioritizing possible changes by identifying the problems that will be resolved by making these changes. By using this approach, the management can prioritize the most number of defective category and focus their attention to this category to help correct and improve the situation. The Pareto chart provides a graphic depiction of the Pareto principle, a theory maintaining that 80% of the output in a given situation or system is produced by 20% of the input (TechTarget, 2018). To appreciate this approach, the proponents presents an instance for the given approach. The data to be used in the sample will be false data since no real data was obtained. The pareto diagram as seen will only be representation of the proponent’s proposal to the management. Order Qty 1 91 2 40 3 90 4 75 5 60 6 43 7 55 White Spot 4 0 10 4 4 4 8 Discontinuous/Unclean Wrong Color Stitches Info Variation Others 1 5 1 4 2 4 1 3 5 3 3 0 5 5 3 0 5 2 3 1 1 4 1 2 2 4 1 0 12 8 9 10 TOTAL 88 97 100 739 7 1 3 8 5 3 1 0 4 50 27 37 Table 5.0 Chart for Tallying Defects 2 3 3 21 0 1 0 11 The data above shows that a there is a total of 739 and with this there are 50 defectives from white spots, 27 from unclean stitching, 37 from wrong information, 21 from color variance and 11 from others. NO. OF DEFECTS Cumulative White Spot 50 50 34% Discontinuous/Unclean Stitches 27 77 53% Wrong Info 37 114 78% Color Variation 21 135 92% Others 11 146 100% DEFECT Cumulative Percent Table 6.0 Computation for Pareto Diagram The table above shows the computation for the Pareto diagram. The table’s computation was acquired through the data from table 5.0. the table shows the cumulative of each defective category and the cumulative percent of each. 13 Table 7.0 Pareto Diagram The table above shows the Pareto diagram. It was obtained through creating a histogram showing the comparison of the tally of defects. The line which represents the cumulative percent divides the graph into 80% and 20%. The defective category that falls on the upper 20% are wrong info and with white spot. Therefore, the management should focus on this issue as well as create a solution for this. The proponents hope that this representation will help the management understand the approach and will consider it. 14 Appendix A (Industrial Quality Control Checklist) 1.) Quality Assurance Department Is there one? None Is there an existing similar section or group that carries out the function of quality assurance? What? Only Maam Marlyn. What are functions entrusted to this group? Who are members of this group? Who do they report to? If none to questions above, how do they maintain quality of their output? 100% inspection 2) Detail of the Quality Control / Monitoring System or Procedure What is the quality characteristic monitored (some dimension or breaking strength, etc)? The cleanliness of the output, the information (jersey numbers, surnames), uniformity of stitches. Do they conduct 100% inspection or sampling inspection? 100% or none at all especially if the order is rushed. Who designed the inspection procedure (sampling plan)? What is their inspection procedure? Describe in detail. By looking at the products, they see visually what are the defects. 3) All Forms filled out and Reports prepared related to sampling inspection and defectives found during inspection and their samples. 4) All Reports or its summary submitted to management concerning #3 5) How does #4 help ensure that quality of products and / or services are maintained? 6) Is management satisfied with the functions of the present quality assurance group? 15 Appendix B (Documentation) Examples of defective items caused by Heat Pressing Issues and Wrong information 16 Sublimation Process 17