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Fabric Inspection System.<br /> <br />Fabric inspection and QC is one of the major areas in textile and garment sector. To establish a workable system for inspecting and evaluating piece goods shipments is vital. No single accepted system for measuring the quality of fabrics, but some of the more commonly used systems are described in this section. <br /> <br />We recommend a minimum of 10% inspection of fabrics prior to spreading. Some are intending to inspect the goods while spreading. However this is unrealistic and the spreaders are not the QC. <br /> <br />1-Ten-Point System<br /> <br />In 1955, the Ten-Point System for piece goods evaluation was approved and adopted by the Textile Distributor's Institute and National Federation of Textiles. This system assigns penalty points to each defect, depending on its length. The Ten-Point System is somewhat complicated because points-per-length vary for warp and filling defects. Table blow shows a breakdown of the points:<br /> <br />Table 1 - Ten-Point System<br /> <br />Warp Defects Penalty Filling Defects Penalty<br />10-36 inches 10 points Full width 10 points<br />5-10 inches 5 points 5 inches - 1/2 the width of goods 5 points<br />1-5 inches 3 points 1-5 inches 3 points<br />Up to 1 inch 1 point <br /> <br />Under the Ten-Point System, a piece is graded a "first" if the total penalty points do not exceed the total yardage of the piece. A piece is graded a "second" if the total penalty points exceed the total yardage of the piece. <br /> <br />2- Four-Point System<br /> <br />The Four-Point System has received the widest acceptance in both the textile and needle trades because it is the most lenient. It is simple and easy to understand. Since it is the most widely used?<br /> <br />2.1- Amount to Inspect - Inspect at least 10% of the total rolls in the shipment.<br /> <br />2.2- Selection of Rolls Select at least one roll of each color. If more than one roll per color must be inspected, then select the number of additional rolls in proportion to the total rolls per color received.<br /> <br />2-3 Defect Classification The Four-Point System classifies defects as shown in Table 2:<br /> <br />Table 2 Four-Point System<br />Size of Defect Penalty<br />3 inches or less 1 point<br />Over 3, but not over 6 inches 2 points<br />Over 6, but not over 9 inches 3 points<br />Over 9 inches 4 points <br /> <br />A maximum of four points is charged to one linear yard.<br /> <br />The length of the defect is used to determine the penalty point. Only major defects are considered. (A major defect is any defect that, if found in a finished garment, would classify that garment as a second.) No penalty points are recorded or assigned for minor defects.<br /> <br /><br /><br /><br />Major defects are classified as follows:<br /> <br />- Major woven fabric defects are slubs, hole, missing yarn, conspicuous yarn variation, end out, soiled yarn, wrong yarn.<br /> <br /> <br />- Major knitted fabric defects are mixed yarn, yarn variation, runner, needle line, barre, slub, hole, and press off.<br /> <br />- Major dye or printing defects are out of register, dye spots, machine stop, color out, color smear, or shading.<br /> <br />- Suppliers using the Four-Point System should obtain examples of major defects and minor defects, and make them available as visual aids for the Inspectors.<br /> <br />2.4- Acceptance Point - Count Most suppliers use 40 points per 100 yards as the acceptable defect rate. However, you should establish your acceptance point-count based on your product and its end use.<br /> <br />2.5- Acceptance Criteria - There are two methods of determining whether a shipment is acceptable. You must decide which method will fit your product. The methods available are as follows:<br /> <br /> <br />One method of acceptance uses a projection of total defects based on the number of defects found during inspection of a sample. Here is an example using this method:<br /> <br />Total yardage received: 2,400 yards<br />Acceptance point-count: 40 per 100 yards<br />Total yards inspected: 240 yards<br />Total penalty points found in the sample inspection: 148 points<br />148 / 240 X 100 = 61.7 points per 100 yards. <br />(Allowance is 40 points per 100 yards.)<br />Action: Shipment would fail.<br /> <br /> <br />A second method is acceptance of 10% bad rolls. <br />Here is an example of the method:<br />Total yardage received: 2,400 yards<br />Acceptance point count: 40 per 100 yards<br />Total yards inspected: 7 (10 % rolls)<br />Number of rolls rejected: 2<br />2 / 7 = 29% rolls rejected.<br />Action: As 29% of rolls inspected were rejected, the shipment would be held for a decision.<br /> ------------------------------------------------------------------------------------------------------------<br /> <br />You must decide whether to reject the entire shipment and return it to the piece goods source, or whether to 100% inspect the balance of the rolls. Management must make this decision; do not leave such decisions to the Inspector or Quality Control Supervisor. If you need production from the good rolls, it may be to your advantage to 100% inspect.<br /> <br />2.6- Inspection Procedure This procedure shows the steps necessary to ensure an effective piece goods quality control program:<br /> <br />* Determine the amount to inspect,<br /> <br />* Select the rolls to inspect,<br /> <br />* Put the rolls on the inspection machine or other viewing device,<br /> <br />Cut off a 6-inch piece across the width of the goods. Mark this piece so that the Inspector will know the right and left sides of the fabric. Use the strip to check for shading side-to-side and end-to-end by checking it at least once against the middle of the roll and once at the other end,<br /> <br />· Inspect for visual defects at a speed slow enough to find the defects,<br /> <br />· Check that the roll contains the yardage as stated by the piece goods source,<br />· Check for skewed, biased, and bowed fabric. Predetermine the tolerance you will allow; this will depend on your product.<br /> <br />· Example: Width of Fabric Tolerance<br /> (In Inches) (In Inches)<br /> 45-50 1<br /> 50-60 1 1/2<br /> <br />Weigh the roll of fabric to determine yield: Yards/Weight = Yield<br /> <br />Example: <br />Weight of roll = 35 pounds<br /> Yards in roll = 59.5 yards<br /> 59.5 / 35 = 1.70 yield.<br /> <br />If major defects are not cut out of the fabric by the Inspector, mark them on the selvage (for example with colored threads). Should you later want to review the defects with the piece goods representative, the defects can be easily located on the inspection machine. In addition, the defects can be easily noted by the Spreader so that they can be cut out.<br /> <br />Record the defects on a report form. (See the suggested Piece Goods Quality Control Inspection Report form on the following page. Please note that this is only a suggested report form. Since report forms can require a variety of detailed information, make sure that your report form contains all the information you need. The original version of our suggested form is enclosed at the back of this manual for duplication purposes.)<br /> <br />Do not require data on the form that you will not use. Recording data is a labor cost, so keep your form simple.<br /> <br />2.7- Possible Considerations for Rejection In addition to excessive defects, the following are common reasons for rejecting fabric rolls:<br /> <br />No roll with a length of less than 25 yards should be accepted as first quality. You may want to specify this on your purchase order.<br /> <br />No roll containing more than one splice should be accepted as first quality.<br /> <br />No roll containing a splice part less than XX* yards should be accepted as first quality. (You may not want to receive rolls with a splice near the beginning or end of the roll.) |
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