Right-First-Time Dyeing Reprocessing Cost Penalty

The formula

This is the expression the tool evaluates. Every term is named underneath, with the unit it must be supplied in.

How the result is derived

Step by step, from the values you type to the figure on screen.

1. The 11 inputs are read from the form on every keystroke: Batch Weight, Batches per Month, Right-First-Time Rate, Failures Fixed by Addition, Addition Cycle Time, Strip & Redye Time, Machine Cost per Hour, Steam Consumption, Steam Cost, Addition Chemicals and Strip & Redye Chemicals.
2. Each value is checked against the accepted range in the input table below. A value outside its range stops the calculation rather than producing a misleading figure — the results blank out and a message appears.
3. The validated values are substituted into the expression above, which resolves Monthly Reprocessing Cost together with every supporting figure in one pass — no value is carried over from a previous entry.
4. The supporting outputs — Batches Failing, Cost of One Addition, Cost of One Strip & Redye, Reprocessing Cost per Batch Dyed, Value of One RFT Point and Machine Hours Consumed — come from the same pass, so they always describe the same case as the headline figure.
5. Results are rounded for display only. The full-precision value is used throughout the chain, so reading a rounded intermediate figure back into the tool by hand can shift the last digit.

What each input means

Where to read each value on the floor, the unit it must be in, and the range the tool accepts.

What the tool returns

The headline figure and every supporting value it is built from.

Worked example

The tool loads with this case already solved — the Monthly Reprocessing Cost shown above is its answer. Change one value and the difference from this baseline is the sensitivity of the result to that variable.

How to use it

1. Work through the input groups in order — Dyehouse and Reprocessing Cost. The defaults are a realistic case, so you can change one value at a time and watch what moves.
2. There is no calculate button. Every figure recalculates as you type or drag, which is what makes this usable for a what-if sweep rather than a single answer.
3. Read Monthly Reprocessing Cost in the dark results panel — that is the headline figure, expressed in /month.
4. Check the supporting rows underneath (Batches Failing, Cost of One Addition, Cost of One Strip & Redye, Reprocessing Cost per Batch Dyed, Value of One RFT Point and Machine Hours Consumed) before acting on the headline — they are where an implausible input usually shows itself first.
5. Reset to defaults returns every field to the reference case, which is the quickest way to check whether a surprising result came from the tool or from an input you had changed earlier.

Where this is used

• Process planning — establishing Monthly Reprocessing Cost before a trial is booked, so machine time and material in Machine Performance & OEE are committed against a calculated figure rather than an estimate.
• Costing and quotation — Monthly Reprocessing Cost is an input to the cost sheet, and quoting from a worked number rather than a remembered one is what keeps a margin intact.
• Troubleshooting — when the floor result drifts from plan, entering the measured values (starting with Batch Weight) shows how much of the gap in Monthly Reprocessing Cost each variable explains.
• Teaching and study — the accepted ranges bracket normal Machine Performance & OEE practice, so moving one variable at a time shows the shape of the relationship rather than a single answer.

Assumptions and limits

• Only the direct cost of reprocessing appears here, and it is usually the smaller half. Lost machine capacity in a dyehouse running near full is worth more than the chemicals and steam, because every reprocessed batch displaces a saleable one; the machine hours figure is there to be valued at your own contribution rate rather than at machine cost. Fabric quality loss after stripping, delivery delay and the risk of outright rejection are excluded entirely. The value of an RFT point also assumes the failure mix stays the same as RFT improves, whereas the easy failures usually go first and the residual mix worsens.
• Every input is bounded to the range normal practice occupies (Batch Weight 10 to 10000 kg, Batches per Month 1 to 5000 no. and Right-First-Time Rate 30 to 100 %, and so on for the rest). Those bounds are guard rails against typing errors, not a claim that the formula fails one unit outside them.
• The calculation is deterministic: the same inputs always give the same result. It carries no allowance for machine condition, operator skill, ambient conditions or lot-to-lot material variation unless an input above explicitly represents one.
• Nothing is sent anywhere. The maths runs in your browser, so the numbers you type never leave the page.

Questions people ask