The maximum width of plastic packaging film (blown film) depends primarily on the die specifications, blown film machine configuration, material type, and process control.
1. Common Blown Film Width Range (based on finished product "flat width")
Minimum width: 50–100 mm
Regular range: 200–1200 mm
Larger width (regular large machines): 1500–2500 mm
This range covers most plastic packaging bags:
Courier bags, garment bags, garbage bags, food bags, pallet cover bags, etc.
Ultra-wide blown film (large or customized equipment)
Maximum flat width: 3000–4000 mm
Corresponding unfolded circumference: 6000–8000 mm
This is generally used for:
Large industrial bags
Pallet covers
Construction/agricultural films
Heavy-duty packaging liner bags
2. Understanding the maximum width from the "die diameter" (more professional)
Simple formula reference:
Flat width ≈ Die diameter × Blow-up ratio ÷ 2
3. Influence of materials on maximum width (very crucial)
Different materials have different controllable width limits:
HDPE
Suitable for wide widths
Thin, stiff, stable
Commonly used for garbage bags, courier bags
LDPE / LLDPE
Good toughness
Ultra-wide widths require higher process control
Three-layer co-extrusion / ABA
Better width stability
More suitable for large-sized, high-demand products
4. Actual production is also limited by these factors
Even if the die can produce the width, it doesn't mean stable mass production is possible. Other factors include:
Blown film machine traction height
Cooling air ring efficiency
Flattening frame and winding width
Thickness requirements (thinner films are harder to control width)
Whether subsequent bag making, punching, and sealing are required
Many factories leave a 10-20% safety margin on the "theoretical maximum width"
5. Determining if the equipment can produce a certain size
Only these 3 pieces of information are needed:
What is the die diameter?
Single layer / ABA / Three-layer co-extrusion
Required thickness range (micron)
