The Machine Direction Orientation (MDO) zone is the most demanding section of a film production line, requiring the stretching rollers to withstand massive line tensions and sharp speed deltas while maintaining absolute thermal equilibrium. Our MDO Stretching Roll is engineered to eliminate local thermal variance and web tracking errors, ensuring stable, high-ratio film orientation.
Advanced Multi-Channel Internal Fluid Design: Utilizing Computational Fluid Dynamics (CFD), the internal double-shell spiral fluid channels accelerate cooling or heating medium velocity, ensuring an ultra-stable surface temperature deviation of within ±0.5°C to avoid uneven polymer crystallization.
Premium Heavy-Duty Surface Coatings: Depending on your film characteristics, we offer high-grade Hard Chrome Plating, Thermal Spray Ceramic, or Tungsten Carbide (HVOF) coatings with surface hardness exceeding HRC 65 to resist the harsh abrasive wear of running films.
Sub-Micron Geometric Precision: Coaxiality, cylindricity, and straightness are restricted to within ≤0.008mm. This eliminates high-speed micro-vibrations and localized tension spikes, ensuring a uniform drawing gap and flawless film flatness.
Optimized Anti-Stick & Friction Properties: Surface textures are precisely controlled (from mirror finish to micro-structured matte) to provide the optimal grip needed for high-draw-ratio speed differentials without sticking or marking.
| Technical Parameters | Specification Range / Value |
| Coaxiality / Cylindricity | ≤ 0.008 mm |
| Straightness | ≤ 0.008 mm |
| Surface Temperature Variation | ±0.5℃ |
| Coating Materials Available | Hard Chrome Plating, HVOF Tungsten Carbide (WC), Ceramic |
| Hardness Range Availability | ≥ HRC 65 (HV 900 – 1300) |
| Surface Roughness | Ra ≤ 0.01 um (Mirror) or Custom Matte (Ra 0.2 – 1.5um) |
This ultra-precision MDO Stretching Roll is universally compatible with global premier orientation machinery (such as Brückner, Hosokawa Alpine, Reifenhäuser, and Davis-Standard), optimized for:
BOPP / BOPET Packaging Lines: High-speed, high-output production requiring rigid drawing ratios and exact optical clarity.
MDO-PE Recyclable Film Lines: Facilitating uniform, reliable longitudinal orientation for mono-material sustainable flexible packaging.
Lithium Battery Separators (Wet/Dry Process): Securing micro-level gauge consistency and consistent porosity mapping during film orientation.
Capacitor & Optical Films: Demanding zero surface checking, ultra-low thermal tolerances, and absolute scratch-free handling.
Q1: Chrome-plated vs. Tungsten Carbide (WC) coating—which is better for an MDO Stretching Roll?
A1: Chrome-plating is excellent for standard optical or packaging applications requiring a mirror finish. However, for films with abrasive additives (like lithium battery separators or heavily matte films) or lines running at extreme speeds, our HVOF Tungsten Carbide coating is recommended due to its extreme hardness (>HRC 68) and exceptional scratch resistance.
Q2: How do you prevent film neck-in or wrinkling during high-ratio stretching?
A2: We customize the surface roughness (Ra) and profile of the stretching roll based on your polymer type and draw gaps. By pairing precise micro-roughness (for controlled air entrapment/release) with exceptional roll straightness (≤0.008mm), we maintain uniform cross-direction web tension to minimize neck-in.
Huatao Group as a premier global leader in web-handling and processing roller technology, the manufacturing excellence and field-tested reliability speak for themselves. Today, we proudly serve as the trusted partner and supplier to more than 40 large-scale BOPP and BOPET film production enterprises worldwide. This proven track record underscores our unique ability to meet the most stringent industrial demands for extreme line speeds, massive cross-widths, and 24/7 continuous high-load stability.
Our state-of-the-art manufacturing facility houses heavy-duty CNC cylindrical grinding machines, high-speed dynamic balancing rigs, and advanced fully automated vertical electroplating lines, capable of processing custom rollers up to Ø3500mm in diameter and 12000mm in length. Backed by robust hydrostatic and laser geometric validation systems, we guarantee that every roll delivered delivers peak performance, allowing modern film production lines to operate with absolute confidence.