slitter upper blade & holder

What do Slitter Upper Blades Mean?

“Slitter Upper Blades” are crucial rotary cutting tools used in slitting machines to cut wide rolls of material (such as paper, film, foil, textiles, rubber, or metal) into narrower widths. The Slitter Upper Blade typically works in conjunction with a stationary lower blade (or anvil) to perform the slitting operation. The material being processed passes between the rotating Slitter Upper Blade and the lower blade, resulting in a precise and clean cut. These upper blades are circular and are driven to rotate at a controlled speed. The design of the Slitter Upper Blade, including its diameter, thickness, edge profile, and the material it’s made from, is critical for achieving accurate slitting widths, clean-cut edges, and efficient slitting processes. Slitter Upper Blades are also sometimes referred to as “top slitter knives,” “rotary slitting blades,” “circular slitting knives,” “male slitter blades,” or “disc cutters,” depending on the specific application and the type of slitting machine.

Uses and Applications of Slitter Upper Blades

Slitter Upper Blades are fundamental in a wide range of industries that convert web-based materials:

• Paper Industry: Slitting large rolls of paper into narrower rolls for printing, packaging, newsprint, and other paper products.
• Film and Foil Converting: Slitting plastic films (e.g., BOPP, PET, PVC), aluminum foil, and laminates for packaging, industrial applications, and consumer goods.
• Adhesive Tape Manufacturing: Slitting wide rolls of adhesive tapes into various widths for consumer, industrial, and medical use.
• Textile Industry: Slitting rolls of fabrics, non-wovens, and technical textiles into narrower strips for garment manufacturing, industrial applications, and home textiles.
• Rubber and Tire Manufacturing: Slitting rubber sheets and other rubber materials for gaskets, seals, and tire components.
• Metal Processing: Slitting coils of steel, aluminum, copper, and other metals into narrower strips for further manufacturing processes.
• Label and Tag Manufacturing: Slitting wide webs of label stock and tag materials into multiple lanes or individual rolls.
• Packaging Industry: Creating specific widths of flexible packaging materials and cardboard.

The specific design, material, and edge geometry of the Slitter Upper Blade are chosen based on the type of material being slit, the required slitting speed, the desired edge quality, and the slitting method employed (e.g., shear slitting, score slitting, crush cutting).

Common Materials for Slitter Upper Blades

The materials used to manufacture Slitter Upper Blades are selected for their hardness, wear resistance to withstand continuous rotation and contact with the web material and the lower blade, and their ability to maintain a sharp and precise cutting edge. Common materials include:

• Tool Steels (e.g., D2, M2, A2, O1, SKD-11): Offer a good balance of hardness, toughness, and wear resistance, suitable for a wide range of materials and production volumes.
• High Carbon Steel (e.g., 52100, 1095): Provides high hardness and the ability to take a sharp edge, suitable for some paper and film applications. May require coatings for enhanced wear and corrosion resistance.
• High-Speed Steel (HSS) (e.g., M2, M4, SKH-51): Offers excellent hardness and wear resistance, especially at higher operating temperatures, making it suitable for demanding, high-speed applications.
• Alloy Steels (e.g., 9CrSi, Cr12MoV): Provide good wear resistance and toughness, often used for slitting various paper, plastic, and metal materials.
• Tungsten Carbide: Offers exceptional hardness and wear resistance, ideal for high-speed slitting of abrasive materials and for extended blade life, reducing downtime. Often used as solid carbide blades or as carbide-tipped blades.
• Ceramic Materials: In specialized applications, ceramic blades offer very high precision and are particularly suitable for thin films and foils due to their sharp cutting edges and wear resistance.

Coatings are frequently applied to Slitter Upper Blades to further enhance their performance and lifespan. Common coatings include:

• Hard Chrome Plating: Increases surface hardness and corrosion resistance.
• Titanium Nitride (TiN): Improves surface hardness and reduces friction.
• Chromium Nitride (CrN): Offers excellent wear and corrosion resistance.
• Diamond-Like Carbon (DLC): Provides very low friction and high hardness, beneficial for preventing material buildup and ensuring clean cuts.

The selection of the blade material and coating depends on the specific materials being slit, the production speed, and the desired blade lifespan and cut quality.

Common Shapes and Features of Slitter Upper Blades

Slitter Upper Blades are primarily circular but come in various edge geometries and features to optimize slitting performance:

• Straight Edge Blades: The most common type, with a flat, sharp outer circumference.
• Beveled Edge Blades: The cutting edge is angled to provide a sharper cut and reduce drag. The bevel angle varies depending on the material being slit and the slitting method. Single bevel, double bevel, and compound bevel designs exist.
• Dished Blades (Concave Blades): Have a concave profile, often used in score slitting or crush cutting applications to apply pressure and fracture the material.
• Perforating Blades: Feature small notches or teeth along the circumference to create perforations in the material.
• Score Slitting Blades: Designed with a rounded or flat edge to create a score line rather than a complete cut, allowing for easy tearing later.
• Crush Cut Blades: Often have a flat or slightly rounded edge and rely on pressure against a hard anvil to fracture the material.
• Shear Slitting Blades: Designed to overlap or run with a precise gap against a lower blade, providing a clean scissor-like cut.

Slitter Upper Blades also feature a central bore for mounting onto the slitting machine’s arbor or shaft. The bore size and any keyways or drive features are critical for secure and accurate rotation. Precise grinding and finishing of the blade edges are essential for achieving clean and consistent cuts.

If you don’t find the blade you are looking for, we can also customize it. See our “Custom Blades” to learn how! Welcome to inquire!

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Why Choose Metal?

1. One-stop hassle-free import service

Easy to enjoy the convenience of importing, from transportation to customs clearance, we handle the whole process, you just need to pay VAT and wait for the goods to arrive at the company.

2. Competitive Pricing

We have seen its blades used in countless applications and is ready to handle whatever project you throw our way -delivering accuracy, durability, and unmatched competitive pricing.

3. ODM & OEM Available

Whether you provide drawings, sketches or samples, we are able to draw and manufacture for you. We also have the ability to assist in modifying existing designs and specifications to improve almost any industrial tooling application. Please contact our dedicated sales team to discuss your specific requirements.

4. Quality Control

A series of testing and inspections are performed to control quality, including first article inspection, Incoming material inspection, and materials certified, In-process quality inspection, Final quality inspection.

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Whether you are an importer, distributor, wholesaler or end-user, we welcome you to join us with minimum MOQ, no hassle for inquiry and more freedom for purchasing.

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