Buying a bag-making machine: the 9 factors that set the price

1. Bag format first, machine second

The most common mistake: choosing a machine first and then trying to adapt the bag format. The reverse is correct. A stand-up pouch with zipper, a 4-side-seal bag and a 3D liner are structurally different products requiring different tooling, folding stations and seal geometries.

So define: base shape, dimensions, bottom construction, closure. Only then does the machine family follow.

• Base shape: flat pouch, stand-up, 3-side seal, 4-side seal, 3D liner
• Bag dimensions including tolerance band
• Bottom construction: with or without gusset, centre bottom seam
• Closure: zipper, valve, spout, open for later sealing

2. Material structure decides the technology line

Laminates are forgiving to seal: a wide temperature range still yields a usable seam. Pure PE mono-material is not. The window between "not sealed" and "melted through" is narrow.

If recyclable mono-material packaging is your goal, you need pulse sealing with a defined temperature profile and active cooling. A machine with conventional continuous heating will not deliver that reproducibly, and this decision cannot be retrofitted later.

3. Calculate output realistically

Catalogue figures apply to an ideal bag in continuous operation. Your actual output is net cycle minus reel change, format change, sample checks and scrap.

Work from annual volume and a defensible availability assumption, not bags per minute. A slower machine with shorter set-up can deliver more bags than a faster one when changeovers are frequent.

4. Changeover: the underestimated cost block

At three format changes per week and two hours each you lose roughly 300 hours per year. Recipe-based systems with servo axes reduce that to reel change and sample check.

Ask specifically: how many recipes can be stored? Which axes move automatically and which are set by hand? How long is the change between two of your real formats, not two ideal ones?

5. Added elements inline or separate

Valves, spouts and zippers can be applied on the same machine or in a second operation. Inline costs more to buy and less to run: no handling of half-finished bags, no intermediate storage, one fewer source of error.

Also clarify which specific valve or spout type is intended. Feeding and sealing tools are matched to it. Changing closure supplier later can mean conversion work.

6. Match the control platform to your maintenance team

A technically superior control your team cannot support is the worse choice when a fault occurs. Check which platform your maintenance staff know and where spare parts are available quickly.

In the DLP series most models use Panasonic controls; the DLP-4500 sealing machine uses a Siemens PLC.

7. Inspection technology where faults are expensive

Camera and thermographic inspection cost extra. They pay off where a fault is expensive: large containers with high fill value, sterile barrier systems, liquids with leak risk.

For simple small-format dry goods the surcharge usually cannot be justified. Decide on the cost of failure, not on technical appeal.

8. Settle CE conformity in writing

For EU operation the machine must be conform in its specific configuration. Before signing, clarify who issues the declaration of conformity, which standards apply and which documents are supplied.

This matters particularly for imported machines. A general "it is CE" is not enough. You need the documentation for your machine.

9. Service and total cost over the life cycle

The purchase price is the smaller part. Over ten years spare parts, sealing bars, maintenance, training and downtime add up.

Ask about response time on faults, spare-part availability in Europe, the scope of operator training and remote support. A ten per cent price advantage is irrelevant if a machine waits three days for a part.