XIAOPAI · Wenzhou Xiaopai Electric Power Technology Co., Ltd. · Zhejiang, China
A blown film machine does five things in a row. It melts resin, pushes it through a die as a tube, inflates and cools that tube, flattens it, and winds it. Every section on the machine exists to hold one of those five steps steady, and a fault in any one of them travels downstream into the roll. The ABC65/75/65-1800 three-layer line is a useful example because its sections separate cleanly and each one carries a number a buyer can check.THE FIVE STEPS, AND WHERE EACH SECTION SITS
Resin enters at the hopper and melts across three extruders. From there it leaves through the die as a tube, expands against internal air pressure, cools in the air ring, collapses at the herringbone, and winds. That order is fixed. What changes between machines is how well each step is held. Reading a blown film machine section by section is faster than reading a parameter list. A parameter tells you what the machine can do on a good day. A section tells you what happens on a bad one.SECTION ONE: THREE SCREWS, AND WHY ONE IS BIGGER
The extrusion section on the line XIAOPAI supplies runs screws of 65, 75 and 65 mm at an L/D of 30:1. They are made from 38CrMoAl with a PTA alloy coating and a nitrided surface. Gearboxes are 180, 200 and 180, with 20CrMnTi gears that are carburised and then ground, fed by an external oil circulation system. Motors are 30, 37 and 30 kW Siemens Beide torque motors, each with an inverter of matching rating. The middle screw is the larger one because it feeds the core layer, and the core is usually the thickest of the three. That is the mechanical reason the model number reads 65/75/65 rather than three equal barrels. The full decoding of those digits sits in the screw article on this site; what matters here is that the extrusion section sets the output ceiling for everything downstream. It also sets how steady that output is, and closed-loop profile control at the die is where the first correction happens.SECTION TWO: THE DIE AND THE AIR RING
The die decides two things at once. It sets the tube diameter the bubble will start from, and it sets how evenly the melt leaves around the circumference. A die that runs two percent thick in one segment sends that error all the way to the winder. What counts as a profile fault, and what counts as normal variation, is worth settling before a machine is ordered, and profile on a web is the right place to start. The air ring decides how quickly the film sets. Cooling comes from a 15 kW centrifugal blower on a variable frequency drive, feeding the ring around the die. Faster cooling locks the film sooner and limits how far it can be drawn. Slower cooling allows more draw and a thinner gauge, and the trade is bubble stability.SECTION THREE: THE BUBBLE CAGE AND THE HERRINGBONE
Above the air ring sits the bubble cage, which on this line uses aluminium rollers and runs electrically. Its job is to stop the bubble from wandering as it rises. A bubble that drifts changes the gauge distribution on its own, no matter how good the die is. The herringbone brings the two sides of the tube together and collapses it. The rollers here are aluminium with a brown oxidation treatment. Set the herringbone badly and the film arrives at the nip with wrinkles, which then get wound into the roll and stay there.SECTION FOUR: THE SECOND PLATFORM
The second platform carries three devices that all act before the film is wound. An ultrasonic edge position controller keeps the web centred. A corona treater raises surface energy, which has to be set before winding and cannot be added later. An automatic tension sensor reads the actual web, which matters because the take-off geometry is not constant on a rotating haul-off. Corona treatment on corona treatment for flex-pack films depends on dwell time and power density, and both are easier to control when the web path is short and straight. The edge controller is only as good as the web guiding loop behind it.SECTION FIVE: THE ROTARY HAUL-OFF
The haul-off on this line turns. The nip rollers, the guide rollers and the winder rotate together around the bubble axis while the bubble itself stays still, so the point where the film is taken off walks around the circumference. That movement is what keeps a thick lane from stacking in one place. Without it, a segment of die lip running two percent thick puts that lane at the same angular position on every wrap. Fifty wraps later the roll has a ridge on one side and a soft sector opposite. Rotation turns the same material into a shallow spiral instead. It is the section buyers skip most often and the one that decides whether the roll runs quietly on a 1300 horizontal slitting machine. A ridge, a hard band and a soft band look similar on a roll and have three different causes, which is why naming web handling defects properly saves time later.SECTION SIX: THE WINDER
The winder is a surface friction type with a 16 N·m torque motor, an inflatable shaft and a winding speed range of 10 to 100 m/min. Maximum roll diameter is 1000 mm. Single-sided, double-sided with hydraulic cutting, and automatic winding are the three builds listed. Because the nip line moves on a rotating haul-off, tension cannot be held by a fixed dancer setting. What arrives at the winder matters too. A splice that does not hold speed lands as a tension spike, and zero-speed splice unwinds are one way to keep that spike out of the roll. Across the width, tension is handled by differential shafts rather than by the main drive. A good roll shows up in slitter rewinder efficiency a week later, and a bad one shows up in slitting process control the same shift.SECTION SEVEN: THE ELECTRICAL CABINET
Three inverters at 30, 37 and 30 kW drive the three screws, Schneider low-voltage components handle switching and protection, and a temperature controller holds each barrel zone. This is the section that gets the least attention in an offer and causes the most stoppages in the first year.THE NUMBERS THAT BIND THE SECTIONS TOGETHER
Folding diameter reaches 1600 mm and thickness runs from 0.013 to 0.20 mm. Output is 200 to 300 kg/h, and at 0.013 mm the take-up speed is 100 to 120 m/min with output near 200 kg/h. The ±4 percent tolerance applies when running LDPE at 0.15 to 0.20 mm, and nowhere else. Connected power is 110 kW on 380 V, 50 Hz three phase, and the machine measures about 13000 by 5200 by 11000 mm. XIAOPAI publishes each of those figures with its condition attached, and each one belongs to a section. The 1600 mm is the die and the cage. The 110 kW is the motors and the blower. The tolerance belongs to the die, the air ring and the haul-off together. Reading them as one block is how a buyer ends up comparing machines that were never comparable. The tolerance figure in particular only exists because something measures it, and ultrasonic gauging is what makes that measurement possible on a moving bubble.WHAT IT RUNS, AND WHAT THE FILM BECOMES
The line runs LDPE, LLDPE, MLLDPE and HDPE. Film from it goes into food and frozen food packaging, carrier and household bags, and as a substrate for the CI flexo printing platform and later lamination. Material choice changes what the sections have to do, which is why XIAOPAI asks for the film specification before the machine configuration. HDPE needs a different bubble shape and a different die gap from LDPE, and MLLDPE sits between them on toughness and draw. A machine configured for one grade does not simply switch to another without a die and air ring review.WHAT XIAOPAI SUPPLIES
XIAOPAI works with the builders of this line and supplies the ABC65/75/65-1800 three-layer blown film machine together with the downstream stages that turn its film into saleable reels. Wenzhou Xiaopai Electric Power Technology Co., Ltd. holds the interface from Wenzhou: configuration against the film specification, inspection before shipment, installation and commissioning on site, training on the actual line, and a spare-parts list with availability noted. The document set is English throughout. The full parameter table for the ABC65/75/65-1800 three-layer blown film line is published, section by section. Read it that way, and ask which number each section is responsible for before the offer is signed.ONE LINE FOR THE RECORD
A blown film machine is five steps held steady by seven sections. Judge it section by section, because a single parameter on its own describes a machine nobody can build.
