The Specialist in Expander Rolls
Osaka Senshoku Machinery Co., Ltd.
With over 70 years of expertise and experience, we eliminate wrinkles and shrinkage in films, paper, metal foils, and non-woven fabrics.
Osaka Senshoku Machinery Co.,Ltd,
Field-Proven! Optimal Installation and Adjustment Guidelines for Expander Rolls
To reliably prevent wrinkles and distortion in production lines for films, paper, and non-woven fabrics, the "correct installation" of an expander roll is absolutely critical. Based on proven on-site standards from around the world, we present the optimal installation procedures and key tips to maximize the wrinkle elimination effect.
Maximize the Effect!
The Golden Ratio for Installation Distances (Web Path)
Setting the distance (web path) between the expander roll and the preceding/succeeding rolls is the most critical factor that directly affects the spreading performance.
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Short Lead-out Distance (Distance A to the Next Roll)
The distance from the expander roll to the next roll the web touches should be kept as short as possible.
As a general guideline, a distance of approximately 2.5 times the expander roll's diameter is considered optimal.
If this distance is too long, there is a risk that the effectively spread web will shrink or develop wrinkles again before reaching the next roll.
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Long Lead-in Distance (Distance B from the Preceding Roll)
The distance from the preceding roll to the expander roll should be longer than the lead-out distance.
As a general guideline, the optimal length is approximately 2 to 3 times (or more) the lead-out distance.
If this distance is too short, it can hinder the spreading effect of the expander roll.
Conversely, if the distance is too long, it can cause the web to slip, which accelerates the wear of the rubber on the roll surface, so caution is required.
Wrap Angle and Web Path Routing
Because the roll's curvature is utilized to smooth out wrinkles, there are strict theoretical guidelines for the web's entry angle and routing.
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Entry from the Concave Side
The web must always enter from the concave side of the roll.
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Equalization of Entry and Exit Angles
As a basic setting to prevent wrinkles, the entry angle and exit angle must be set equally.
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Adjusting the Wrap Angle According to the Material
The optimal wrap angle varies depending on the target material and its thickness.
For example, precise adjustments tailored to the material are required: 15–30 degrees for paper and paperboard, 45–60 degrees for standard films (PP/PA) of 8–20 microns, and 60–90 degrees for ultra-thin films of 1–6 microns.
Strict Horizontal and Parallel Alignment
The accuracy of the alignment when installing the roll on the machine frame also determines the success of wrinkle elimination.
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Maintaining Perpendicularity and Horizontality: Position the roll so that it intersects the web horizontally and at a perfect right angle.
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Parallelism and Centerline Alignment: Exact parallelism with the preceding and succeeding rolls, as well as accurate centerline alignment, are absolute requirements.
[Important] Optimal Settings Vary by Material and Conditions! Leave the Perfect Setup to the Professionals.
While we have introduced the basic installation methods, in an actual manufacturing environment, the optimal settings change in complex ways depending on line speed, web tension, and material characteristics.
Determining the perfect adjustments solely on your own requires a tremendous amount of time and effort.
The Strengths of Our Expander Rolls and Support System
Osaka Senshoku Machinery's expander rolls can be used in either rotational direction.
The rubber surface is highly resistant to chemicals such as dyes, pigments, acids, and alkalis.
Furthermore, it offers excellent heat and abrasion resistance, ensuring long-term, stable performance even in severe operating environments.
Why Not Verify the Results on Your Actual Line?
If you are unsure about the exact location or angle to install the roll in your current production line, please consult with us. We not only propose the optimal installation layout tailored to your specific line conditions, but we also offer "test sample rolls" so you can experience the results firsthand on your actual line.