Rubber Stripper Rings for Metal Slitting Applications

Rubber Stripper Rings

Description

Nordic Company custom manufactures Stripper Rings to suit your specific requirements.

  • The Nordic Company’s Stripper Rings are manufactured from a time tested and field proven proprietary nitrile formula. There is no one else who has this recipe. Our material is engineered to resist damage from oil, to retain its size and shape and resists stretching, and can be maintained by grinding.
  • We can also offer stripper rings with fiber reinforcement to help maintain fit for demanding applications.
  • We provide different types of fit for the ID of the rings to the spacers. Beside the most common request of snug fit, we can also make them tight, slip or loose.
  • We can provide vibrant colors which are easily identifiable when dirty and in low light.
  • We have 30 years of experience of solutions to your technical problems and advice for proper use and care of rubber stripper rings.

    Types

    We offer several types of Rubber Stripper Rings

    • Male and Female Configuration
    • Unbonded or Bonded to your spacers
    • Single Durometer
    • Dual Durometer
    • Proprietary fiber reinforced rings
    • Hub and clamp rings (sheet slitter or slear rings)
    • Mandrel Expanders (Filler Rings)

    Ordering Information

    Information Required for Quotes and Orders

    1. Outside Diameter

    For specific recommendations on knife diameter to rubber diameter, please contact us.

    2. Inside Diameter

    Should match the OD size of your metal spacers. We will automagically adjust the fit to your requested type of fit (see box at right). We have to know the actual OD of your spacers in order to properly manufacture your rings.

    3. Durometer Hardness

    Choose from 60, 70 or 80 Shore A.

    4. Color

    You can choose any one of our vibrant colors.

    5. Quantities of Each Thickness

    Thickness should be the spacer widths. Please don’t add or subtract clearances.

    Standard Tolerances

    OD: +0.010/-0.010″

    ID: Snug fit (most common),
    but we can make tight fit, slip fit or loose fit too

    Thickness: +0.010/-0.030″

    Common Questions

    What is the difference between Buna N, Nitrile, neoprene, and neapolitan?

    Rubber is rubber. What’s the big deal?

    There are various types of materials used to make elastomers. The term elastomer refers to any polymer with elastic properties, or “rubber-like” properties.

    How long do rubber stripper rings last?

    How often should I grind my stripper rings?

    What durometer rings are best?

    That depends on a number of factors, but the most important is the thickness of the material that you are cutting. But, here’s a hint.  Harder durometer shouldn’t be used for hard to cut materials. We see that mistake a lot.  Why don’t you email  or call to discuss.  Yes, we answer the phone.

    Dual durometer stripper rings are the best? Right?

    How thick should the inner layer be on dual durometer rubber?

    What about triple durometer rubber?

    Do you offer clamping groove rubber rings?

    Yes, we can custom manufacture rubber rings with clamping grooves to suit your specific requirements. Contact us with your requirements.

    What is standard when it comes to hardness, fit, OD relationships, etc?

    Does oil causes rubber to stretch?

    Not unless you are using rings made from an inappropriate formula. Rubber doesn’t stretch due to oil. Nordic Company’s rubber stripper rings are specifically formulated to resist attack by oils.

    Do I need a harder rubber to resist stretching?

    No, when rubber gets compressed, it doesn’t return to its original size. It gets very close, but not quite. That happens on the next compression cycle, and the next. Think about how many compression cycles (revolutions) your rings turn in a production shift.

    For very small compressions, you might get millions or hundreds of millions of cycles before you have a noticeable change. But, large compressions cause noticeable changes with fewer cycles. With a sufficiently large compression, you may notice it after just one cycle.

    When rubber rings fail to return to their original size, they become longer in circumference, which means they are larger in diameter. This results in a looser fit or may cause them to become loose on the inside diameter (ID).

    You can’t control the number of cycles (hey, you’ve got to get through that warehouse of coils, right?), but you can control the amount of compression by managing the diameter relationship of the knives and rubbers. Don’t over-compress the rubbers.

    Shouldn’t dual durometer rings stop that from happening? No. (see above)

    We do manufacture a proprietary fiber-reinforced ring, which helps rings keep their snugness longer. Contact us directly for details.

    Technical Advice

    Grinding Stripper Rings

    Grinding rubber rings seems very simple because rubber is a lot softer than knives. But it is devilishly difficult.

    • You need a special grinding wheel dedicated for grinding rubber rings
    • Rubber is abrasive, so imagine grinding one grinding wheel with another
    • Heat is a problem because rubber is an insulator and the heat doesn’t get wicked away like with metal.
    • Heat is a problem because heat causes the diameter to increase
    • It’s difficult to keep rubber rings from spinning (they aren’t keyed)
    • The dang things move out of the way when the grinding wheel presses against them.

    Diameter relationship of knives and rubbers

     

     

     

     

     

     

    Bonded rubber rings

    Nordic Company can bond rubber to new or existing spacers in our facility. We’ve had great success with our technique and with the performance of our rings.

    Rubber rings permanently bonded to steel spacers is a great way to improve a number of nagging problems.  They will never get loose and go around like a hula hoop. Your regrinder will be able to hold better diameter accuracy and circularity because he won’t have your rings going around like a hula hoop either. Your personnel will be handing 1 piece rather than 2 (spacer and ring).

    On the other hand, you’ve got to send spacers and the rubbers bonded out for grinding, so you might need more tooling.  And, when it comes time for new knives, you’ll have to send the spacers to Nordic Company to have the old rubber removed and new rubber applied.

    Either that has to be done during shutdown maintenance, or you’ll need more tooling to cover things while they are in our shop.

    We can help you to plan a conversion or to recover your existing spacers.