The complete line explained - preforms, stretch blow machines, air systems and layout - with indicative 2026 price bands.
Every PET bottle in the world starts as a preform - a thick, test-tube shaped piece of plastic with the bottle's neck already moulded into it. Heat it, stretch it into a mould with high-pressure air, and ten seconds later you have a finished bottle. That simplicity is why PET owns the beverage world.
But between preform and pallet sits a line with four systems - and one of them, the air system, is the single most under-specified piece of equipment in the industry. This guide walks the whole line. The machines live on our blow moulding machines page; the full business plan is in our water bottling plant guide.
The Raw MaterialYour preform decides almost everything: the neck size fixes your cap, the weight fixes your bottle's strength, and the availability of preforms in your country fixes your supply chain. Most new plants buy preforms from regional suppliers - our raw materials division supplies them too. Only at high volumes does making preforms in-house (with an injection machine and preform moulds) become worthwhile.
Hopper, elevator and unscrambler feeding preforms to the oven - manual loading on semi-automatic, fully automatic above that.
Infrared lamps soften the preform body (never the neck). Even heating is what separates good bottles from wobbly ones.
The stretch rod and high-pressure air form the bottle inside the mould in under 10 seconds per cycle.
High-pressure compressor, dryer and air recovery - the system everyone forgets to size until bottles come out thin.
PET blowing needs high-pressure air at 30-40 bar - five to ten times your workshop compressor. Get this wrong and no machine setting will save your bottles: thin walls, pear-shaped bodies and rejected batches all trace back to starved air.
Booster or piston type, sized to the machine's CFM demand at full cavitation - not average use. Under-sizing is the #1 cause of poor bottle quality.
Moisture in the air line shows up as cloudy bottles. A refrigerated dryer is standard; desiccant for demanding finishes.
Recovers exhaust air to pre-blow the next cycle - cuts compressor energy 20-30 percent. Worth it at any real volume.
Expect $5,000-$25,000 for a properly sized set. Every serious quote - ours included - lists it itemized. See the price guide.
Machine + moulds + air set. 400-900 bph, manual preform loading. The starter configuration.
1,500-2,500 bph with auto loading. Where most growing water brands land.
3,000-6,000 bph, air recovery, full automation for serious volume.
Machine + moulds + air set bands. Freight, duties, installation additional - the import guide covers those steps.
A semi-automatic line needs roughly 25-35 square metres including preform storage and air room; an automatic line 50-80. Power is the other planning item: budget 15-40 kW depending on machine size, plus a stable supply - blowers punish voltage dips. Your quote includes the exact layout drawing and utility schedule before you pour a single foundation.
The cheapest quote usually hides the smallest air set. Buy the air system once, properly.
Too light and bottles fail stacking; too heavy and you donate money to the material supplier with every bottle.
Paying 20-30 percent extra electricity forever to save $3,000 once.
Your machine, your preforms, your moulds - run at full load with video proof before dispatch. The 72-hour standard we apply to every order.
A test-tube shaped piece of PET with the bottle neck already formed. It is reheated and stretch-blown into the final bottle shape - preform to bottle in seconds.
Yes, within its size window - by changing the blow mould set. The neck finish stays fixed by the preform, so one machine can serve 500 ml to 2 L bottles with the same neck.
High-pressure air at 30-40 bar. Compressor sizing is the most common under-specification in PET lines - your quote includes the exact CFM and pressure for your bottle range.
Semi-automatic suits outputs below roughly 3,000 bottles per day. Fully automatic pays for itself above that through labour savings and consistent cycle times.
Semi-automatic machines produce 400-900 bottles per hour; fully automatic machines from 1,500 to 6,000+ bph depending on cavitation and bottle size.
Send your bottle size and target output - get a full line layout, air system sizing and itemized quote within 24 hours.