Quick answer: Your material’s width — film, paper roll or sheet — is the single specification that eliminates the most machines from your shortlist. Bag lines run 320–1300 mm roll widths (VFD paper bag family), film blowing runs 600–1500 mm (VSJ family), thermoforming sheet runs 400–700 mm (VCT/VPT). Send your width first; everything else follows.
When buyers describe their requirement, they lead with the product: “I make shopping bags”, “I produce yogurt cups”. The factory engineers lead with something else: the width of the material going in. Because width — not speed, not price — decides which machine frame can physically accept your job.
The width ranges that matter
Paper converting (bag lines): roll widths from 320 mm (small bakery bags) to 1300 mm (large retail carriers). A buyer with 600 mm rolls is in a different machine class than one with 1200 mm — even for the same finished bag.
Film blowing: 600–1500 mm lay-flat across the VSJ family. Your bag machine’s working width must fit inside what the bubble produces, with gusseting in between if flat-fold matters.
Thermoforming sheet: 400–700 mm sheet widths across VCT/VPT classes, matched to forming area. A 670 mm sheet roll on a 500 mm machine is a non-starter.
Non-woven converting (caps, shoe covers, bags): roll width plus GSM together decide the feed system.
The three width mistakes
1. Quoting finished size instead of material width. “My bag is 30×40 cm” — but on what roll width, with what gusset? The machine takes the roll, not the bag.
2. Forgetting gusset and hem consumption. Flat film width ≠ bag width once gussets, seals and hems consume material. Tell the engineer the finished dimensions AND the film width you can source; let them do the conversion.
3. Unit confusion. “56 cm” vs “560 mm” vs “22 inches” — all the same width, three conversations. Send millimeters; it removes one round-trip from every quotation.
The two-line email that gets accurate quotes
Write to any machinery supplier — us included — with these two lines and you’ll skip three rounds of clarification:
> Finished product: [dimensions, gusset, handle/no handle]
> Material: [type, GSM or thickness, roll width you can source]
That’s the whole technical brief for a first quotation. The supplier’s engineer can map your width to a machine frame immediately — and tell you honestly if your width points to a different machine family than you assumed.
VIE Machinery engineers lines around your material spec — paper bag, film blowing, thermoforming and converting families, all width-matched at quotation stage: https://viemachinery.com