Budget hot-melt carton sealing: measurements, worked example and comparison

Define the job and measurement boundary

Weigh adhesive consumption for a representative run of qualified seals. Record purges, rejects and recovered adhesive with a consistent gross-input boundary.

Estimate a circular bead from measured application geometry and entered density. Flattened, intermittent or foamed applications need measured dosage instead.

Work through the numbers

A measured 0.3 g net dose for 10,000 good cartons needs 3 kg net adhesive, or 3.15789 kg at a stated 5% gross-input loss.

Grams/carton = π × Diameter² / 4 × Total path × Density / 1,000 A 1 mm circular bead over 400 mm at 0.95 g/cm³ uses about 0.29845 g.

Gross adhesive kg = Dose × Good cartons / 1,000 / Yield 0.3 g × 10,000 / 1,000 / 0.95 = 3.15789 kg.

Adhesive cost/good carton = Dose × Price/kg / 1,000 / Yield 0.3 g × EUR 4/kg / 1,000 / 0.95 = EUR 0.001263 per good carton.

Avoid the comparison error

A theoretical round bead is only a geometry estimate. Flattening and intermittent deposits require a weighed dose; adhesive cost cannot determine adequate bonding.

• Circular uniform bead model, not a bond-strength recommendation.
• Use a weigh-back sample to validate dispensing and density.
• Loss on gross input, not an extra percentage on net output.
• Do not add the same purge loss both to dose and loss.
• Adhesive material only; excludes energy, applicator and labour.
• Application efficiency and bond qualification are separate.

Prepare a comparable purchasing decision

Replace each example with dated measurements and confirmed charges for the same SKU and job. Keep unresolved specification differences visible rather than ranking incompatible offers.

Record the original quote unit, material scope, fixed charges, freight and valid quantity tier. Review an alternative as a separate scenario before adding it to the complete packaging cost.

Common questions