Define the purchasing question
A useful wrap trial measures material consumed on a reproducible set of loads while preserving the required containment performance.
Compare old and new measured averages over an entered planning quantity. Document performance qualification alongside the cost result.
Collect measurements that match the calculation
Weigh the same roll before and after a trial on a suitable scale; divide the net mass difference by completed loads. Record load geometry, wrap program, operators, film lot and rewrap count. Repeat representative conditions.
Compare representative measured consumption after performance qualification. The planning period is the entered load count, not an assumed year.
- Measured old grams per load (g)
- Measured new grams per load (g)
- Loads in explicit period (units)
Work through an illustrative case
Saved kg = (Old grams − New grams) × Loads ÷ 1,000
70 g saved on 10,000 loads is 700 kg.
Replace these illustrative inputs with measured data or a quotation for the same scope. Change one assumption at a time so that a difference can be traced to a dimension, quantity, charge or process change.
Avoid the expensive comparison error
One unusually successful load is not a reliable average. A lower film mass obtained by omitting required wraps is not an equivalent process.
- Use measured quantities and charges valid for this exact specification and period.
- Cost calculations do not qualify performance, protection or a supplier.
Case: measure three representative wrap runs
An illustrative run of 10 qualified pallets uses 3.2 kg net film; another uses 3.0 kg for 10; a third uses 3.1 kg for 10. Combined net use is 9.3 kg over 30 loads, or 310 g/load.
At an entered EUR 2.40/kg, material allocation is EUR 0.744/load. Keep core tare, rewraps, rejected loads and the approved wrap pattern explicit. This small worked dataset demonstrates arithmetic, not a guaranteed consumption distribution.
Common questions
What should I verify before using this result?
Weigh the same roll before and after a trial on a suitable scale; divide the net mass difference by completed loads. Record load geometry, wrap program, operators, film lot and rewrap count. Repeat representative conditions.
Does this calculation approve the packaging?
No. It estimates only the stated quantity, conversion or cost boundary. Technical performance and any required test or supplier approval remain separate.
Download the worksheets
CSV files open in spreadsheet applications. Examples are illustrative and contain no personal data.