A good specification describes your product, packs, output, accuracy and packaging material in numbers. It also covers your utilities, the standards that apply, the documents you expect and the acceptance tests. Makers quote against it, and the factory test checks the machine against it.
A specification also makes quotes comparable. Without one, each maker quotes the machine it prefers to sell, and you cannot tell which offer gives more.
Keep it practical. A few pages with clear numbers work better than a long document full of general wishes. Mark which points are essential and which are preferences, so makers can propose sensible alternatives.
Product and pack
- Name each product and describe its form: powder, granules, pieces, liquid or paste.
- State bulk density, particle size, moisture, temperature and any stickiness, dust or fragility.
- List every pack size by weight or volume, with bag or pouch dimensions.
- State the pack style, such as pillow, gusseted, stand-up or zipper pouch, sachet or carton.
- Give the film or pouch specification, including structure, thickness, reel width and core size, and send samples.
- List coding, labelling, nitrogen flushing, tear notches or hang holes you need.
Performance
- Speed in packs per minute for each pack size, with your product.
- Filling accuracy as a standard deviation or a range at stated confidence, as explained in filling accuracy.
- Seal strength and leak-free rate, with the test method.
- Maximum changeover time between pack sizes and products.
- Expected running hours per day, so the maker can size components for the duty.
Build, compliance and support
- Contact parts in stainless steel 304 or 316, stated by part group.
- Your voltage, frequency, phases and compressed air supply.
- The electrical and safety standards for your market, such as CE marking for the EU, covered in CE marking for machinery.
- Preferred brands for the PLC, HMI, drives and pneumatics, and the HMI language.
- Documents: manuals, electrical drawings, parts list, certificates and the PLC program.
- Spare parts and change parts to ship with the machine, plus warranty and support terms.
Acceptance tests
Write the factory test protocol into the specification. State the product, film and pack sizes to be run, how long each run lasts, and the pass criteria for speed, weight, seal quality and changeover time. Ship your own product and film to the factory for the test, as described in FAT and SAT.
Repeat the key tests at your site after installation. Conditions there, such as humidity and product temperature, may change the results. State in the contract what happens if the machine fails a test, and how long the maker has to correct it.
Next step
We help you write the specification, send it to shortlisted makers and witness the factory test against it. To start, book a free sourcing review.