Process & QC — Regrind Ratio & Properties
Regrind Ratio & Properties for injection molding process control.
Closed-loop 25% regrind reaches a stable equilibrium — some pellets have seen many heats, but their share shrinks geometrically. The blend math shows why 25% works forever while 50% spirals: the tail of multi-pass material stops being negligible.
Formula
Note: Starting-point process values — the resin grade's datasheet and an in-mold study govern. Verify with a gate-seal study and a cooling-time ladder on the actual tool.
Regrind Ratio & Properties for injection molding process control. A free injection molding cycle & process tool — no sign-up, no upload, instant results in your browser.
About Process & QC — Regrind Ratio & Properties
Process & QC — Regrind Ratio & Properties computes the governing relationship retention = virgin share + regrind share × (1−loss)^passes live as you type. Closed-loop 25% regrind reaches a stable equilibrium — some pellets have seen many heats, but their share shrinks geometrically. The blend math shows why 25% works forever while 50% spirals: the tail of multi-pass material stops being negligible. Defaults are pre-filled with realistic values for this exact scenario, and the worked example substitutes your numbers step by step so the math is never a black box.
How to use Process & QC — Regrind Ratio & Properties
- 1Enter your values — Regrind fraction, Heat histories in regrind, Property loss per pass (sensible defaults are pre-filled).
- 2Read the live results: Blend property retention.
- 3Check the "with your numbers" line to see retention = virgin share + regrind share × (1−loss)^passes substituted step by step.
- 4Adjust inputs until the scenario matches yours, then copy or share the result.
Why use Process & QC — Regrind Ratio & Properties?
- ✓Instant, free and private — every calculation runs client-side in your browser; nothing is uploaded
- ✓Built on the stated formula retention = virgin share + regrind share × (1−loss)^passes with authoritative sources cited on the page (Rosato, Injection Molding Handbook, 3rd ed.; Osswald & Hernández-Ortiz, Polymer Processing — Modeling and Simulation)
- ✓Closed-loop 25% regrind reaches a stable equilibrium — some pellets have seen many heats, but their share shrinks geometrically.
- ✓Niche-specific defaults give a meaningful worked answer the moment the page loads
Frequently asked questions
What formula does the process & qc — regrind ratio & properties use?+
It evaluates retention = virgin share + regrind share × (1−loss)^passes, exactly as published. Sources: Rosato, Injection Molding Handbook, 3rd ed.; Osswald & Hernández-Ortiz, Polymer Processing — Modeling and Simulation. The substituted worked example on the page lets you verify every step against the textbook.
How should I read the result — and how far can I trust it?+
Closed-loop 25% regrind reaches a stable equilibrium — some pellets have seen many heats, but their share shrinks geometrically. Starting-point process values — the resin grade's datasheet and an in-mold study govern. Verify with a gate-seal study and a cooling-time ladder on the actual tool.
When is this calculator the right tool for the job?+
Regrind Ratio & Properties for injection molding process control. A free injection molding cycle & process tool. The blend math shows why 25% works forever while 50% spirals: the tail of multi-pass material stops being negligible. For neighbouring scenarios, the related tools below cover the same engine with different presets.
Do I need to install anything or create an account?+
No. The tool is pure client-side JavaScript: open the page and it works, offline once loaded, with no account, no quota and no data leaving your device.
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