{"id":1004,"date":"2026-09-08T08:29:22","date_gmt":"2026-09-08T08:29:22","guid":{"rendered":"https:\/\/isbmmolding.com\/?p=1004"},"modified":"2026-09-08T08:29:22","modified_gmt":"2026-09-08T08:29:22","slug":"what-is-the-main-difference-between-extrusion-blow-molding-and-injection-blow-molding","status":"publish","type":"post","link":"https:\/\/isbmmolding.com\/de\/what-is-the-main-difference-between-extrusion-blow-molding-and-injection-blow-molding\/","title":{"rendered":"Worin besteht der Hauptunterschied zwischen Extrusionsblasformen und Spritzblasformen?"},"content":{"rendered":"
The main difference between extrusion blow moulding (EBM) and injection blow moulding (IBM) is how the plastic intermediate is formed before blowing. In EBM, it is extruded as a continuous tube (parison). In IBM, it is injection-moulded as a precise preform on a core rod. This difference determines the container types, dimensional accuracy, resins, and applications each process serves.<\/p>\n
In EBM, a continuous extruder pushes molten plastic through a die to form a hollow tube called a parison. The parison hangs between open mould halves; when it reaches the correct length, the mould closes, pinching the bottom, and blow air inflates it against the mould walls. The parison\u2019s wall thickness is set by the die gap and drawdown \u2014 less precise than an injection-moulded preform. Neck finish is formed by the pinching mould, producing a seam at the base and lower neck precision than IBM. EBM handles large containers, integral handles, and resins like HDPE and PP that extrude well.<\/p>\n
In IBM, plastic is injection-moulded around a core rod, forming a precise preform with the finished neck thread already moulded. The core rod transfers the preform to the blow station where air pressure inflates it. IBM produces containers with: accurate and consistent neck thread dimensions (critical for pharmaceutical closure compatibility); no base pinch seam (the bottom of IBM containers is seamless); precise weight control per cavity; and no waste trim. IBM is the preferred process for small pharmaceutical vials, dropper bottles, and HDPE personal care containers.<\/p>\n
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IBM: the injected preform on a core rod provides more precise neck geometry and seamless base than EBM\u2019s pinched parison.<\/p>\n