{"id":2949,"date":"2026-08-11T17:25:34","date_gmt":"2026-08-11T09:25:34","guid":{"rendered":"https:\/\/www.jcinjectionmolding.com\/?p=2949"},"modified":"2026-08-07T18:31:35","modified_gmt":"2026-08-07T10:31:35","slug":"cold-runner-injection-mold-manufacturing","status":"publish","type":"process","link":"https:\/\/www.jcinjectionmolding.com\/ko\/service\/cold-runner-injection-mold-manufacturing\/","title":{"rendered":"Cold Runner Injection Mold Manufacturing"},"content":{"rendered":"
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\ube44\uc6a9 \ud6a8\uc728\uc801\uc778 Cold Runner Mold<\/strong> manufacturing for versatile plastic part production. Built with precision 2-plate or 3-plate mold bases, cold runner tooling provides low upfront tooling costs, simple maintenance, and rapid material or color changes during \ud50c\ub77c\uc2a4\ud2f1 \uc0ac\ucd9c \uc131\ud615<\/strong> runs.<\/p>\n<\/section>\n

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Cold Runner Mold Structures: 2-Plate vs. 3-Plate Molds<\/h2>\n

Cold runner systems solidify the runner channel during each cycle alongside the part. We engineer two distinct mold plate configurations based on your gate location needs:<\/p>\n

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Two-Plate Cold Runner Molds (2-Plate)<\/p>\n

The most common and economical mold structure. The parting line opens once to eject both the molded parts and the connected runner sprue together. Utilizes edge gates, sub-gates (tunnel gates), or direct sprues. Ideal for simple part geometries and low-to-medium volume production.<\/p>\n<\/div>\n

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Three-Plate Cold Runner Molds (3-Plate)<\/p>\n

Features two distinct parting lines. One opening ejects the runner system while the second opens to eject the parts. Allows pinpoint gating directly on top of the part center, enabling automatic runner degating without the cost of a Hot Runner Mold<\/strong>.<\/p>\n<\/div>\n<\/div>\n<\/section>\n

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Cold Runner vs. Hot Runner Tooling Matrix<\/h2>\n

Comparing conventional cold runners against hot runner systems helps determine the most economical tooling path for your production budget:<\/p>\n\n\n\n\n\n\n\n\n
Tooling Attribute<\/th>\nCold Runner Mold<\/th>\nHot Runner System Tooling<\/th>\n<\/tr>\n<\/thead>\n
Upfront Tooling Cost<\/td>\nSignificantly Lower (No heated manifolds or electronics)<\/td>\nHigher (Requires heated manifold blocks & controllers)<\/td>\n<\/tr>\n
Maintenance Complexity<\/td>\nSimple & Inexpensive (Mechanical cleaning & polishing)<\/td>\nComplex (Requires tip replacement & electrical wiring checks)<\/td>\n<\/tr>\n
Color & Resin Changes<\/td>\nFast & Easy (Ideal for frequent material changes)<\/td>\nSlower (Requires purging heated internal manifold channels)<\/td>\n<\/tr>\n
Heat-Sensitive Polymers<\/td>\nExcellent (Zero risk of thermal degradation in runner)<\/td>\nRequires strict temperature control (Risk of degradation)<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<\/section>\n

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Tooling Engineering: Sprue Design, Sub-Gates & Runner Regrind Optimization<\/h2>\n

Proper cold runner sizing balances fill pressure against runner waste during \ub9de\ucda4 \uae08\ud615 \uc81c\uc791<\/strong>:<\/p>\n

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1. Trapezoidal & Full-Round Runner Profiles<\/p>\n

We engineer full-round or modified trapezoidal runner channels using 5-axis CNC milling. This maximizes volume-to-surface-area ratios, reducing pressure drops and preventing premature melt freeze-off.<\/p>\n<\/div>\n

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2. Automatic Sub-Gates & Tunnel Degating<\/p>\n

To eliminate manual trimming labor, we machine tunnel sub-gates or banana gates below the parting line. The runner shears off automatically upon part ejection, delivering clean gate cosmetics on \uc800\uc6a9\ub7c9 \uc0ac\ucd9c \uc131\ud615<\/strong> runs.<\/p>\n<\/div>\n

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3. Heat-Sensitive Resin Protection (PVC & Thermoplastics)<\/p>\n

Thermally unstable polymers like Polyvinyl Chloride (PVC)<\/strong>, ABS<\/strong>, \ubc0f \ud3f4\ub9ac\uce74\ubcf4\ub124\uc774\ud2b8(PC)<\/strong> benefit from cold runners. Because resin moves continuously without residing in heated manifolds, thermal degradation and acid gas outgassing are completely avoided.<\/p>\n<\/div>\n

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4. Efficient Sprue Regrind Recycling<\/p>\n

Solid cold runners can be granulating into regrind and blended back with virgin resin at controlled ratios (typically 10% to 20%), recovering material costs on non-critical industrial parts.<\/p>\n<\/div>\n<\/div>\n<\/section>\n

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Ideal Application Scenarios for Cold Runner Tooling<\/h2>\n