Water Bottle Shrink Film Specification
Why can two rolls of equal length have different material mass?
"These are invented teaching inputs, not equipment ratings, market prices or an accepted tolerance. The two scenarios change one assumption while holding the other inputs constant. Use the comparison to identify what must be measured or agreed for your project."
Two planning scenarios
Record item,Unit,Scenario A,Scenario B,How to establish this input
Film length,m,1200,1200,"Use the applicable drawing revision or an actual dimension record, with the stated unit. Identify internal, external, usable or clearance dimensions explicitly. A nominal catalogue dimension does not establish the installed usable space."
Film width,mm,550,550,"Use the applicable drawing revision or an actual dimension record, with the stated unit. Identify internal, external, usable or clearance dimensions explicitly. A nominal catalogue dimension does not establish the installed usable space."
Film thickness,μm,45,55,"Use the applicable drawing revision or an actual dimension record, with the stated unit. Identify internal, external, usable or clearance dimensions explicitly. A nominal catalogue dimension does not establish the installed usable space."
Film density,kg/m³,920,920,"Retain the material or fluid identity, operating condition, declared reference basis and source for the load, property or dose. Check whether a supplier value is measured, specified or assumed before applying it to the actual process."
Calculated comparison
Record item,Unit,Scenario A,Scenario B
Mass,kg,27.324,33.396
What the comparison means,"Length, width and density stay unchanged while film thickness increases. The estimated material mass rises even though roll length is identical. Keep core and outer wrap separate from film mass. This comparison supports inventory reconciliation; it does not select a shrink-temperature recipe or establish acceptable film variation."
Evidence to request,"Collect usable length, width, thickness basis, material density and core identification from the actual material specification. Compare like-for-like net film mass rather than gross delivered roll weight."
Input assumptions,"Identify the bottle, pack or material configuration, operating mode and measurement boundary. State the start and finish of the observation and which accepted output the comparison represents; unlike boundaries cannot establish a performance improvement."
How to establish this input,"Mark every input as measured, taken from a drawing, quoted or assumed. Retain the source document identifier, revision, date and responsible person. The same numeral with a different unit or data status is not automatically a comparable input."
Project decision record,Ask the responsible supplier and buyer to agree actual acceptance criteria and the evidence that will demonstrate them. Teaching values and calculated outputs on this page do not become approved operating settings or contractual performance guarantees.
Evidence to request,"Record the decision affected by the result, the measurement or trial still needed, its owner and the next review. Keep unresolved items visible in the handover file instead of changing the figures to make a preferred equipment option appear acceptable."
Two planning scenarios,"These are invented teaching inputs, not equipment ratings, market prices or an accepted tolerance. The two scenarios change one assumption while holding the other inputs constant. Use the comparison to identify what must be measured or agreed for your project."