{"id":2995,"date":"2026-05-16T07:18:12","date_gmt":"2026-05-16T07:18:12","guid":{"rendered":"https:\/\/www.advantage.co.th\/?p=2995"},"modified":"2026-05-16T07:18:21","modified_gmt":"2026-05-16T07:18:21","slug":"major-causes-of-ng-non-good-defects-in-plastic-injection-manufacturing-for-automotive-parts","status":"publish","type":"post","link":"https:\/\/www.advantage.co.th\/th\/major-causes-of-ng-non-good-defects-in-plastic-injection-manufacturing-for-automotive-parts\/","title":{"rendered":"Major Causes of NG (Non-Good Defects) in Plastic Injection Manufacturing for Automotive Parts"},"content":{"rendered":"<p class=\"wp-block-paragraph\">Plastic injection molding is one of the most important manufacturing processes in the automotive industry. It is widely used for producing interior parts, exterior components, connectors, housings, clips, air ducts, and precision engineering plastic parts.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Because automotive parts require high precision, appearance quality, strength, and durability, strict quality control is essential. Any defect or NG (Non-Good) part can affect vehicle safety, assembly performance, and customer satisfaction.<\/p>\n\n\n\n<hr class=\"wp-block-separator has-alpha-channel-opacity\"\/>\n\n\n\n<h1 class=\"wp-block-heading\">Major NG Areas in Plastic Injection Automotive Parts Manufacturing<\/h1>\n\n\n\n<h2 class=\"wp-block-heading\">1. Short Shot<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">Short shot occurs when molten plastic does not completely fill the mold cavity.<\/p>\n\n\n\n<h3 class=\"wp-block-heading\">How It Happens<\/h3>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Low injection pressure<\/li>\n\n\n\n<li>Insufficient material<\/li>\n\n\n\n<li>Poor mold venting<\/li>\n\n\n\n<li>Low mold temperature<\/li>\n\n\n\n<li>Blocked gate or runner<\/li>\n\n\n\n<li>Thin wall design<\/li>\n<\/ul>\n\n\n\n<h3 class=\"wp-block-heading\">Common Result<\/h3>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Incomplete part shape<\/li>\n\n\n\n<li>Missing corner or edge<\/li>\n\n\n\n<li>Weak structure<\/li>\n\n\n\n<li>\u0e04\u0e27\u0e32\u0e21\u0e25\u0e49\u0e21\u0e40\u0e2b\u0e25\u0e27\u0e43\u0e19\u0e01\u0e32\u0e23\u0e1b\u0e23\u0e30\u0e01\u0e2d\u0e1a (Assembly Failure)<\/li>\n<\/ul>\n\n\n\n<hr class=\"wp-block-separator has-alpha-channel-opacity\"\/>\n\n\n\n<h1 class=\"wp-block-heading\">2. Flash Defect<\/h1>\n\n\n\n<p class=\"wp-block-paragraph\">Flash is excess plastic material leaking outside the mold parting line.<\/p>\n\n\n\n<h3 class=\"wp-block-heading\">How It Happens<\/h3>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Excessive injection pressure<\/li>\n\n\n\n<li>Worn mold surface<\/li>\n\n\n\n<li>Improper mold clamping force<\/li>\n\n\n\n<li>Mold misalignment<\/li>\n\n\n\n<li>Damaged mold tooling<\/li>\n<\/ul>\n\n\n\n<h3 class=\"wp-block-heading\">Common Result<\/h3>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Sharp edge on product<\/li>\n\n\n\n<li>Poor appearance<\/li>\n\n\n\n<li>Additional trimming process<\/li>\n\n\n\n<li>Customer rejection<\/li>\n<\/ul>\n\n\n\n<hr class=\"wp-block-separator has-alpha-channel-opacity\"\/>\n\n\n\n<h1 class=\"wp-block-heading\">3. Sink Mark<\/h1>\n\n\n\n<p class=\"wp-block-paragraph\">Sink marks appear as small dents or depressions on the plastic surface.<\/p>\n\n\n\n<h3 class=\"wp-block-heading\">How It Happens<\/h3>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Uneven wall thickness<\/li>\n\n\n\n<li>Improper cooling<\/li>\n\n\n\n<li>Low holding pressure<\/li>\n\n\n\n<li>Excessive material shrinkage<\/li>\n\n\n\n<li>Thick rib design<\/li>\n<\/ul>\n\n\n\n<h3 class=\"wp-block-heading\">Common Result<\/h3>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Poor cosmetic appearance<\/li>\n\n\n\n<li>Surface deformation<\/li>\n\n\n\n<li>Dimensional instability<\/li>\n<\/ul>\n\n\n\n<p class=\"wp-block-paragraph\">Sink marks are especially critical for automotive interior visible parts.<\/p>\n\n\n\n<hr class=\"wp-block-separator has-alpha-channel-opacity\"\/>\n\n\n\n<h1 class=\"wp-block-heading\">4. Warpage and Deformation<\/h1>\n\n\n\n<p class=\"wp-block-paragraph\">Warpage causes the plastic part to bend or twist after molding.<\/p>\n\n\n\n<h3 class=\"wp-block-heading\">How It Happens<\/h3>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Uneven cooling temperature<\/li>\n\n\n\n<li>Improper mold design<\/li>\n\n\n\n<li>Residual internal stress<\/li>\n\n\n\n<li>Material shrinkage variation<\/li>\n\n\n\n<li>Incorrect cooling cycle<\/li>\n<\/ul>\n\n\n\n<h3 class=\"wp-block-heading\">Common Result<\/h3>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Poor fitting during assembly<\/li>\n\n\n\n<li>Gap issues<\/li>\n\n\n\n<li>Dimensional NG<\/li>\n\n\n\n<li>Functional failure<\/li>\n<\/ul>\n\n\n\n<hr class=\"wp-block-separator has-alpha-channel-opacity\"\/>\n\n\n\n<h1 class=\"wp-block-heading\">5. Burn Mark<\/h1>\n\n\n\n<p class=\"wp-block-paragraph\">Burn marks appear as dark or black discoloration on the molded part.<\/p>\n\n\n\n<h3 class=\"wp-block-heading\">How It Happens<\/h3>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Trapped gas inside mold<\/li>\n\n\n\n<li>Excessive injection speed<\/li>\n\n\n\n<li>Poor mold venting<\/li>\n\n\n\n<li>Material overheating<\/li>\n<\/ul>\n\n\n\n<h3 class=\"wp-block-heading\">Common Result<\/h3>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Surface appearance defect<\/li>\n\n\n\n<li>Weak material structure<\/li>\n\n\n\n<li>Customer complaint<\/li>\n<\/ul>\n\n\n\n<hr class=\"wp-block-separator has-alpha-channel-opacity\"\/>\n\n\n\n<h1 class=\"wp-block-heading\">6. Weld Line<\/h1>\n\n\n\n<p class=\"wp-block-paragraph\">Weld lines occur when two flow fronts of molten plastic meet but do not properly fuse.<\/p>\n\n\n\n<h3 class=\"wp-block-heading\">How It Happens<\/h3>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Low melt temperature<\/li>\n\n\n\n<li>Poor gate location<\/li>\n\n\n\n<li>Slow injection speed<\/li>\n\n\n\n<li>Complex part geometry<\/li>\n<\/ul>\n\n\n\n<h3 class=\"wp-block-heading\">Common Result<\/h3>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Weak mechanical strength<\/li>\n\n\n\n<li>Visible line on surface<\/li>\n\n\n\n<li>Structural crack risk<\/li>\n<\/ul>\n\n\n\n<hr class=\"wp-block-separator has-alpha-channel-opacity\"\/>\n\n\n\n<h1 class=\"wp-block-heading\">7. Black Spot and Contamination<\/h1>\n\n\n\n<p class=\"wp-block-paragraph\">Foreign material contamination is a major issue in automotive plastic parts.<\/p>\n\n\n\n<h3 class=\"wp-block-heading\">How It Happens<\/h3>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Dirty hopper or machine<\/li>\n\n\n\n<li>Mixed material<\/li>\n\n\n\n<li>Burned resin residue<\/li>\n\n\n\n<li>Dust contamination<\/li>\n\n\n\n<li>Recycled material impurity<\/li>\n<\/ul>\n\n\n\n<h3 class=\"wp-block-heading\">Common Result<\/h3>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Surface contamination<\/li>\n\n\n\n<li>Color inconsistency<\/li>\n\n\n\n<li>Functional defect<\/li>\n\n\n\n<li>OEM rejection<\/li>\n<\/ul>\n\n\n\n<hr class=\"wp-block-separator has-alpha-channel-opacity\"\/>\n\n\n\n<h1 class=\"wp-block-heading\">8. Silver Streak \/ Moisture Defect<\/h1>\n\n\n\n<p class=\"wp-block-paragraph\">Silver streaks appear as shiny lines on plastic surfaces.<\/p>\n\n\n\n<h3 class=\"wp-block-heading\">How It Happens<\/h3>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Moisture in resin material<\/li>\n\n\n\n<li>Improper drying condition<\/li>\n\n\n\n<li>Wet recycled material<\/li>\n\n\n\n<li>Excessive material temperature<\/li>\n<\/ul>\n\n\n\n<h3 class=\"wp-block-heading\">Common Result<\/h3>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Poor appearance<\/li>\n\n\n\n<li>Reduced material strength<\/li>\n\n\n\n<li>Surface quality failure<\/li>\n<\/ul>\n\n\n\n<p class=\"wp-block-paragraph\">Engineering plastics for automotive applications require strict drying control.<\/p>\n\n\n\n<hr class=\"wp-block-separator has-alpha-channel-opacity\"\/>\n\n\n\n<h1 class=\"wp-block-heading\">9. Dimensional NG<\/h1>\n\n\n\n<p class=\"wp-block-paragraph\">Automotive plastic parts must meet tight dimensional tolerance.<\/p>\n\n\n\n<h3 class=\"wp-block-heading\">How It Happens<\/h3>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Mold wear<\/li>\n\n\n\n<li>Temperature instability<\/li>\n\n\n\n<li>Material shrinkage variation<\/li>\n\n\n\n<li>Machine setting fluctuation<\/li>\n\n\n\n<li>Poor process control<\/li>\n<\/ul>\n\n\n\n<h3 class=\"wp-block-heading\">Common Result<\/h3>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Assembly interference<\/li>\n\n\n\n<li>Gap mismatch<\/li>\n\n\n\n<li>Functional failure<\/li>\n\n\n\n<li>Production line stoppage<\/li>\n<\/ul>\n\n\n\n<hr class=\"wp-block-separator has-alpha-channel-opacity\"\/>\n\n\n\n<h1 class=\"wp-block-heading\">10. Surface Appearance Defect<\/h1>\n\n\n\n<p class=\"wp-block-paragraph\">Appearance quality is critical for visible automotive components.<\/p>\n\n\n\n<h3 class=\"wp-block-heading\">Common NG Types<\/h3>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Scratch<\/li>\n\n\n\n<li>Dent<\/li>\n\n\n\n<li>Flow mark<\/li>\n\n\n\n<li>Gloss variation<\/li>\n\n\n\n<li>Color variation<\/li>\n<\/ul>\n\n\n\n<h3 class=\"wp-block-heading\">How It Happens<\/h3>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Poor handling<\/li>\n\n\n\n<li>Improper packing<\/li>\n\n\n\n<li>Mold surface damage<\/li>\n\n\n\n<li>Incorrect molding parameter<\/li>\n\n\n\n<li>Material contamination<\/li>\n<\/ul>\n\n\n\n<h3 class=\"wp-block-heading\">Common Result<\/h3>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Customer claim<\/li>\n\n\n\n<li>Rework or scrap<\/li>\n\n\n\n<li>Rejection during final inspection<\/li>\n<\/ul>\n\n\n\n<hr class=\"wp-block-separator has-alpha-channel-opacity\"\/>\n\n\n\n<h1 class=\"wp-block-heading\">Major Scrap Sources in Plastic Injection Manufacturing<\/h1>\n\n\n\n<figure class=\"wp-block-table\"><table class=\"has-fixed-layout\"><thead><tr><th>Production Area<\/th><th>Typical NG \/ Scrap<\/th><\/tr><\/thead><tbody><tr><td>Material Feeding<\/td><td>Moisture contamination<\/td><\/tr><tr><td>Injection Molding<\/td><td>Short shot, flash<\/td><\/tr><tr><td>Cooling Process<\/td><td>Warpage<\/td><\/tr><tr><td>Mold Tooling<\/td><td>Dimensional NG<\/td><\/tr><tr><td>Surface Inspection<\/td><td>Scratch, burn mark<\/td><\/tr><tr><td>Assembly Process<\/td><td>Misfit parts<\/td><\/tr><tr><td>Printing \/ Painting<\/td><td>Color defect<\/td><\/tr><tr><td>Final Inspection<\/td><td>Appearance NG<\/td><\/tr><\/tbody><\/table><\/figure>\n\n\n\n<hr class=\"wp-block-separator has-alpha-channel-opacity\"\/>\n\n\n\n<h1 class=\"wp-block-heading\">How Factories Separate NG and Waste According to BOI Scrap Regulation<\/h1>\n\n\n\n<p class=\"wp-block-paragraph\">Factories operating under Thailand BOI (Board of Investment) privileges must carefully control all production scrap, rejected materials, and defective products because imported raw materials may receive tax exemption benefits.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Proper scrap segregation and traceability are mandatory for BOI compliance.<\/p>\n\n\n\n<hr class=\"wp-block-separator has-alpha-channel-opacity\"\/>\n\n\n\n<h1 class=\"wp-block-heading\">Types of Scrap Classification<\/h1>\n\n\n\n<h2 class=\"wp-block-heading\">1. Plastic Production Scrap<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">Generated during normal production process.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">\u0e15\u0e31\u0e27\u0e2d\u0e22\u0e48\u0e32\u0e07:<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Runner scrap<\/li>\n\n\n\n<li>Sprue scrap<\/li>\n\n\n\n<li>Flash trimming<\/li>\n\n\n\n<li>Start-up purge material<\/li>\n<\/ul>\n\n\n\n<hr class=\"wp-block-separator has-alpha-channel-opacity\"\/>\n\n\n\n<h2 class=\"wp-block-heading\">2. NG Product Scrap<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">Defective molded parts rejected during inspection.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">\u0e15\u0e31\u0e27\u0e2d\u0e22\u0e48\u0e32\u0e07:<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Warped automotive panel<\/li>\n\n\n\n<li>Cracked housing<\/li>\n\n\n\n<li>Burn mark defect<\/li>\n\n\n\n<li>Dimensional NG connector<\/li>\n<\/ul>\n\n\n\n<hr class=\"wp-block-separator has-alpha-channel-opacity\"\/>\n\n\n\n<h2 class=\"wp-block-heading\">3. Raw Material Scrap<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">Unused or contaminated resin materials.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">\u0e15\u0e31\u0e27\u0e2d\u0e22\u0e48\u0e32\u0e07:<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Moisture-damaged resin<\/li>\n\n\n\n<li>Expired engineering plastic<\/li>\n\n\n\n<li>Contaminated pellets<\/li>\n\n\n\n<li>Mixed resin material<\/li>\n<\/ul>\n\n\n\n<hr class=\"wp-block-separator has-alpha-channel-opacity\"\/>\n\n\n\n<h1 class=\"wp-block-heading\">BOI Scrap Separation Process<\/h1>\n\n\n\n<h2 class=\"wp-block-heading\">Step 1 \u2014 Identification and Tagging<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">Factories identify:<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>BOI material<\/li>\n\n\n\n<li>Non-BOI material<\/li>\n\n\n\n<li>Reusable scrap<\/li>\n\n\n\n<li>Non-reusable NG products<\/li>\n<\/ul>\n\n\n\n<p class=\"wp-block-paragraph\">Each scrap lot receives:<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Scrap label<\/li>\n\n\n\n<li>Defect description<\/li>\n\n\n\n<li>Lot traceability<\/li>\n\n\n\n<li>Weight record<\/li>\n\n\n\n<li>Process source<\/li>\n<\/ul>\n\n\n\n<hr class=\"wp-block-separator has-alpha-channel-opacity\"\/>\n\n\n\n<h2 class=\"wp-block-heading\">Step 2 \u2014 Segregated Storage Area<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">Factories establish dedicated areas for:<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>\u0e2a\u0e34\u0e19\u0e04\u0e49\u0e32\u0e17\u0e35\u0e48\u0e44\u0e21\u0e48\u0e1c\u0e48\u0e32\u0e19\u0e04\u0e38\u0e13\u0e20\u0e32\u0e1e (NG Products)<\/li>\n\n\n\n<li>Plastic runners<\/li>\n\n\n\n<li>Regrind material<\/li>\n\n\n\n<li>Destroyed scrap<\/li>\n\n\n\n<li>BOI-controlled waste<\/li>\n<\/ul>\n\n\n\n<p class=\"wp-block-paragraph\">BOI scrap must not mix with local materials.<\/p>\n\n\n\n<hr class=\"wp-block-separator has-alpha-channel-opacity\"\/>\n\n\n\n<h2 class=\"wp-block-heading\">Step 3 \u2014 Scrap Recording and Monitoring<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">Factories maintain records including:<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Material type<\/li>\n\n\n\n<li>Resin grade<\/li>\n\n\n\n<li>Quantity and weight<\/li>\n\n\n\n<li>Production line source<\/li>\n\n\n\n<li>Defect cause<\/li>\n\n\n\n<li>Scrap destination<\/li>\n<\/ul>\n\n\n\n<hr class=\"wp-block-separator has-alpha-channel-opacity\"\/>\n\n\n\n<h2 class=\"wp-block-heading\">Step 4 \u2014 Inspection and Verification<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">Authorized inspection companies verify:<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Actual scrap quantity<\/li>\n\n\n\n<li>Scrap condition<\/li>\n\n\n\n<li>Destruction process<\/li>\n\n\n\n<li>BOI compliance evidence<\/li>\n<\/ul>\n\n\n\n<p class=\"wp-block-paragraph\">Companies such as <a target=\"_blank\" rel=\"noreferrer noopener\" href=\"https:\/\/www.advantage.co.th\/th\/scrap-boi\/?utm_source=chatgpt.com\">Advantage Co., Ltd.<\/a> provide BOI Scrap Inspection services and certification support in Thailand.<\/p>\n\n\n\n<hr class=\"wp-block-separator has-alpha-channel-opacity\"\/>\n\n\n\n<h2 class=\"wp-block-heading\">Step 5 \u2014 Destruction or Recycling<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">Common disposal methods include:<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Crushing<\/li>\n\n\n\n<li>Shredding<\/li>\n\n\n\n<li>Regrinding<\/li>\n\n\n\n<li>Melting<\/li>\n\n\n\n<li>Authorized recycling<\/li>\n<\/ul>\n\n\n\n<p class=\"wp-block-paragraph\">Non-reusable automotive NG parts are often physically destroyed to prevent re-use.<\/p>\n\n\n\n<hr class=\"wp-block-separator has-alpha-channel-opacity\"\/>\n\n\n\n<h2 class=\"wp-block-heading\">Step 6 \u2014 Certificate Issuance<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">Inspection companies issue:<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Scrap inspection certificate<\/li>\n\n\n\n<li>Weight verification report<\/li>\n\n\n\n<li>Destruction evidence<\/li>\n\n\n\n<li>Photo documentation<\/li>\n<\/ul>\n\n\n\n<p class=\"wp-block-paragraph\">These documents support BOI audit and material balance reconciliation.<\/p>\n\n\n\n<hr class=\"wp-block-separator has-alpha-channel-opacity\"\/>\n\n\n\n<h1 class=\"wp-block-heading\">Best Practices to Reduce NG in Plastic Injection Manufacturing<\/h1>\n\n\n\n<h2 class=\"wp-block-heading\">Process Control<\/h2>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Scientific molding control<\/li>\n\n\n\n<li>Injection parameter monitoring<\/li>\n\n\n\n<li>Mold temperature management<\/li>\n\n\n\n<li>SPC quality monitoring<\/li>\n<\/ul>\n\n\n\n<h2 class=\"wp-block-heading\">Material Control<\/h2>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Resin drying system<\/li>\n\n\n\n<li>FIFO material management<\/li>\n\n\n\n<li>Incoming material inspection<\/li>\n\n\n\n<li>Moisture monitoring<\/li>\n<\/ul>\n\n\n\n<h2 class=\"wp-block-heading\">Mold Maintenance<\/h2>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Preventive mold maintenance<\/li>\n\n\n\n<li>Mold cleaning<\/li>\n\n\n\n<li>Venting inspection<\/li>\n\n\n\n<li>Tool wear monitoring<\/li>\n<\/ul>\n\n\n\n<h2 class=\"wp-block-heading\">Automation<\/h2>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Robotic part handling<\/li>\n\n\n\n<li>Vision inspection system<\/li>\n\n\n\n<li>Automated leak and dimension inspection<\/li>\n\n\n\n<li>Traceability barcode system<\/li>\n<\/ul>\n\n\n\n<h2 class=\"wp-block-heading\">Scrap Management<\/h2>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Real-time scrap analysis<\/li>\n\n\n\n<li>Root cause investigation<\/li>\n\n\n\n<li>NG trend monitoring<\/li>\n\n\n\n<li>BOI material tracking system<\/li>\n<\/ul>","protected":false},"excerpt":{"rendered":"<p>Plastic injection molding is one of the most important manufacturing processes in the automotive industry. It is widely used for producing interior parts, exterior components, connectors, housings, clips, air ducts, and precision engineering plastic parts. Because automotive parts require high precision, appearance quality, strength, and durability, strict quality control is essential. Any defect or NG [&hellip;]<\/p>\n","protected":false},"author":3,"featured_media":2996,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"_acf_changed":false,"footnotes":""},"categories":[15],"tags":[54,85,88,48,79],"class_list":["post-2995","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-boi-scrap","tag-boi-inspection","tag-material-and-workmanship","tag-quality-control-inspections","tag-scrap-2","tag-technical-and-performance-validation"],"acf":[],"yoast_head":"<!-- This site is optimized with the Yoast SEO plugin v28.3 - https:\/\/yoast.com\/product\/yoast-seo-wordpress\/ -->\n<title>Major Causes of NG (Non-Good Defects) in Plastic Injection Manufacturing for Automotive Parts - Advantage<\/title>\n<meta name=\"description\" content=\"Plastic injection molding is one of the most important manufacturing processes in the automotive industry. 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