Food bag packaging machine parts fall into four groups by function: feeding and conveying, bag forming and sealing, inspection and control, and auxiliary support. Common parts in each group are listed below.
Feeding and Conveying Parts
Film roll unwinding parts: air shaft, friction shaft, tension damper. They hold and unwind packaging film steadily. The air shaft fits standard plastic film rolls with 76 mm and 150 mm inner diameters. The damper adjusts unwinding tension to prevent film wrinkling or tearing.
Film feed roller set: drive film roller, driven pressure roller, guide roller. They pull flat film along a set path. Some roller surfaces have anti-slip silicone to prevent film slipping or drifting.
Material feeding parts: by product type, vibratory feeder bowls for granules and small pieces, screw conveyors for powders, piston filling heads for liquids and pastes. They feed set amounts of product.
Photoelectric correction parts: photoelectric correction sensor and guide roller. They correct lateral film drift in real time and keep bag forming aligned.
Bag Forming and Sealing Parts
Former parts: by bag type, stainless steel back seal forming plate, three-side seal bag tube, four-side seal forming die. They fold flat film into the required bag shape. This is one of the key parts for bag accuracy.
Longitudinal sealing parts: ceramic or copper heating rod, longitudinal sealing pressure roller, thermocouple. They make the continuous side seal. Heating rod power matches seal width, commonly 200 W to 800 W.
Cross sealing parts: PTFE-coated cross seal heating knife that meets food contact material safety standards, cross seal pressure block, cutting knife with flat or serrated option. They seal the top and bottom of the bag and cut the finished bag from the film.
Coding parts: food-grade ribbon coding head, laser marking head, thermal transfer roller. They print production date, batch number, and other information on the bag surface.
Inspection and Control Parts
Photoelectric sensing parts: color mark sensor, through-beam photoelectric sensor. They detect film color mark position and material presence. With the control system, they support fixed-length bag making and automatic stop when material runs out.
Temperature control parts: smart temperature controller, solid state relay, thermocouple. They control longitudinal and cross seal heating temperature. Temperature error can be kept within ±1°C for consistent seal strength.
Pressure sensing parts: used to monitor filling pressure and sealing pressure. They support filling accuracy and seal tightness.
Automation control parts: main PLC, touch screen, servo or stepper motor and drive. They run the machine, adjust parameters, and trigger fault alarms.
Auxiliary Support Parts
Frame and drive parts: aluminum alloy or carbon steel frame, timing belt, sprocket, deep groove ball bearing housing. They support the machine structure and transmit power for stable operation.
Dust and debris removal parts: small fan, food-grade filter. They clear food crumbs and dust from packaging and keep the machine and workshop clean.
Finished product conveying parts: food-grade belt conveyor, receiving hopper. They catch finished bags and move them to sorting and case packing.
Safety protection parts: emergency stop button, safety light curtain, rotating part guard. They reduce mechanical injury risk and meet national safety standards for food packaging equipment.
If replacement parts are needed for film feed rollers, sealing jaws, forming plates, cutting knives, or drive components, Hansheng Automation can machine them from customer drawings in single pieces or small batches.
