Frequently Asked Questions

What are Grommets?

Grommets are useful in electronics applications when a wire or tube needs to pass through metal or another material that may cause damage. Most commonly, they protect cables from sharp corners and edges.

We offer standard insulation grommets in Buna-N (Nitrile), and we also manufacture Mil-Spec grommets for military applications, vibration mount grommets to protect components from noise & vibration, and other specialty grommets. Grommets can be pushed into place using our grommet inserter tools. For more information on any of our rubber grommets, including Buna-N (Nitrile) grommets, contact us today!

What are Rubber Grommets used for?

In addition to electronics applications, our grommets can be used in a wide variety of industries including aerospace, healthcare, construction, transportation, industrial, and military and defense applications. We serve the OEM and replacement part markets, maintaining inventory for industrial distributors. As a rubber grommet manufacturer, we have earned a reputation for high-quality manufacturing.

What is SBR?

SBR (styrene-butadiene rubber) is a low cost non-pil resistant material. It has good water resistance and resilience up to 70 durometer; compression set becomes poorer with higher durometer; generally satisfactory for most moderate chemicals and wet or dry organic acids. SBR is not recommended for ozone, strong acids, oils, greases, fats and most hydrocarbons. SBR can be molded

What is HNBR material?

HNBR is also known as Highly Saturated Nitrile or HSN. It’s a special class of nitrile rubber that has been hydrogenated to increase the saturation of the butadiene segment of the carbon polymer backbone. 

The compound withstands both hot and cold temperatures and is renowned for its physical toughness.

What is Buna-N?

Nitrile (Buna-N) is a general purpose oil resistant polymer which has good solvent, oil, water and hydraulic fluid resistance, good compression set, abrasion resistance and tensile strength. Nitrile should not be used in highly polar solvents such as acetone, and MEK, ozone, chlorinated hydrocarbons and nitro hydrocarbons

What is EPR material?

Ethylene Propylene (EPR, also called EPDM) is a polymer with outstanding properties. It has exceptionally good weather aging and ozone resistance; excellent water and chemical resistance; excellent resistance to gas permeability, and excellent resistance to aging due to exposure to steam; and heat, resistance excellent up to 350°F. Ethylene Propylene is a polymer where oil and solvent resistance is poor, however, it is fairly good in ketones and alcohols. It is not recommended for food applications or exposure to aromatic hydrocarbons.

What is Transfer Molding?

Transfer molding is similar to compression molding, but has a transfer system on the top of the mold that feeds the rubber into cavities when the press is closed. The major difference between compression and transfer is that the uncured rubber is placed in a pot / ram combination built into the top of the mold.  When pressure is applied by the closing of the press, the ram “transfers” the uncured rubber through small holes (sprues) in the pot directly into the cavities. The balance of the process is the same as is found in compression molding, except that, cure time is reduced due to preheating the rubber during the transfer process; finished parts are more consistent as the mold is closed prior to the transfer; and labor is reduced as preforms do not need to be loaded into the mold.

What is the NAICS Codes for Manufacturing?

NAICS stands for the North American Industry Classification System and is used as the standard for classifying businesses by federal statistics agencies. They use the codes to collect, analyze, and publish statistical data related to the U.S. business economy.

What is Rubber Molding?

Minor Rubber offers custom compression, transfer, injection molding, and latex dip molding of rubber parts, including bellows and boots. For over 100 years, we have been manufacturing high quality molded rubber parts for industrial applications. Our experienced staff has the industry and application expertise to manufacture your custom part to exact specifications, ensuring that we will manufacture your part right the first time and deliver it on time and on budget.

What is Compression Molding?

The most popular molding process, compression molding uses pressure and heat to mold the rubber into the shape required. Compression molding is a good manufacturing choice for large parts, parts that do not require tight tolerances, and low production quantities. It requires inexpensive tooling but is a labor-intensive process with longer loading and process times than other molding methods.

What are the advantages of Compression Molding?

  • Less expensive tooling
  • Good choice for small to large parts
  • Good for parts with inserts
  • Good for low to medium production quantities
  • Good for high durometer parts

What are the Disadvantages of Compression Molding?

  • Longer loading and process time
  • Labor intensive beginning to end
  • Yields the most inconsistent results than either transfer or injection molding processes

What are Vibration Rubber Mount Grommets & Isolators?

Minor Rubber manufactures anti vibration rubber mount grommets & isolators that provide superior vibration suppression, noise reduction, protection from the forces generated during compression, and sealing. We serve the OEM and replacement part markets, and provide inventory for industrial distributors. Our vibration mount grommets are used in electronics, aerospace, healthcare, construction, transportation, and defense applications.

Vibration rubber mount grommets & isolators are designed with two flanges of unequal thickness. The thicker flange acts as the vibration isolator. We maintain an inventory of vibration grommets in a range of sizes, materials and durometer hardness, and colors. If you need a custom insulation grommet for your application, we have the capability to manufacture it for you.