What are the applications of flat mouth circular knives in the plastic industry

Sources：www.cssjlgj.com | PublishDate：2026.05.06

The core of the flat mouth circular knife in the plastic industry is high-speed precision cutting+smooth and burr free cutting, covering the entire process of film, sheet, pipe, composite material and recycling granulation, suitable for soft/hard/foam plastics, and is the main tool for mass production.
1、 Plastic film/soft roll slitting (mainstream)
Packaging film: BOPP, PET, PE, PVC film slitting, used for food/daily chemical packaging, with smooth cuts without burrs, adhesion, or stretching deformation.
Soft PVC/PE: wire and cable insulation layer, medical soft film, greenhouse film cutting, high-speed (300m/min) cutting, tolerance ± 0.01mm.
Composite film: Aluminum plastic composite film and paper plastic composite film are cut without delamination or delamination between layers.
Functional film: Optical film, release film, protective film cut, dust-free, scratch free, suitable for the electronics/photovoltaic industry.
2、 Plastic sheet/board cutting
Hard sheet: PP, PE, PVC, ABS, acrylic sheet (0.5-5mm) cutting, used for vacuum forming, printing, building materials, with vertical cuts, no broken edges, and no whitening.
Foamed plastic: EVA, pearl cotton, PU foam slitting, shockproof packaging materials, no fragmentation, no delamination.
Geotextile: HDPE geomembrane, waterproofing membrane cut, used for infrastructure/water conservancy projects, weather resistant and wear-resistant, continuous cutting stability.
3、 Plastic pipe/profile cutting
Thin walled pipes: PVC, PP, PE plastic pipes (diameter ≤ 110mm) cut to a fixed length, for water supply and drainage/line pipes, with a smooth cut, no burrs, and no flattening.
Irregular profiles: Cut plastic door and window profiles, cable trays, and sealing strips, adapt to extrusion line online cutting, with a regular cross-section and correct size.
4、 Plastic Composite and Component Processing
Plastic tape: PET, BOPP, PVC tape slitting, precise slitting before die-cutting, smooth edges without warping.
Woven bag/non-woven fabric: plastic woven fabric, non-woven fabric cutting, used for bag making/home textile, cutting cleanly and without drawing threads.
Injection molded part gate cutting: Small injection molded parts (such as bottle caps and pipe fittings) gate/flash flat cutting, replacing punching and shearing, with no burrs and high efficiency.
5、 Plastic recycling and granulation
Waste film/silk shredding: Recycling PE/PP film and pre shredding chemical fibers for easy cleaning and granulation, with wear-resistant and anti adhesive blades.
Cutting of scraps: Cutting of scraps from sheet/pipe production, recycling and reuse, compatible with automated recycling lines.
Core advantages (plastic processing adaptation points)
Excellent incision quality: flat blade design, no burrs, no broken edges, no adhesion, reducing post-processing polishing.
High speed and efficiency: With the help of a slitting machine, the speed can reach 300m/min, suitable for mass production lines.
Wide material adaptability: High speed steel/alloy steel/SKD11 material, suitable for soft/hard/foam plastics, wear-resistant and not easy to break.
Low cost: can be repeatedly ground and reused, has a long lifespan, and is easy to maintain.
Common materials and selection references
Soft film/thin material (≤ 1mm): High speed steel (SKH51/W6), thin cutting edge, sharp and wear-resistant.
Hard piece/thick material (1-5mm): Alloy tool steel (9CrSi/CR12MOV), thick cutting edge, impact resistance.
Foam/adhesive plastic: surface coating (TiN), anti sticking and friction reducing.

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