Commutator Manufacturing

Electric Materials has been a leader in commutator manufacturing for over 100 years. Our expertise is recognized throughout the world, and our commutators are in service in some of the most demanding applications in the rail, steel mill, and naval industry. Many advantages to choosing to work with EM over other manufacturers include but are not limited to:

  • Complete start-to-finish manufacturing capabilities for commutator design and production
  • Experts in the commutator rebuilding and refilling of existing commutators
  • Specializes in manufacturing consistent, reliable and high-quality products such as collector rings
  • Depending on the application and customer requirements, the assembly will be processed to the applicable engineering instruction resulting in a finished product that is of the highest quality

commutator design

Commutator Design

Whether you require a commutator based on an existing commutator model or a customized commutator design, our engineers can create a commutator to meet your exact specifications. We have in-depth design capabilities and are registered to IS0 9001:2015.

commutator production

Commutator Production

Electric Materials can manufacture commutators built to existing model specifications, or we can produce new commutators with all new steel parts. Some standard commutator types Electric Materials readily delivers are:

  • V-Ring commutators
  • Glass band commutators
  • Shrink ring commutators

EM also offers wire banded assemblies, commutator bar packs, and mica v-rings designed and produced to your requirements.

v-bound commutator

V-Bound Commutators

V-bound commutators are named for the internal v-shaped configuration that retains the copper bars and mica segments. The copper bar and mica segment pack are bored with a v-shaped groove on each end of the pack. The mica v-rings are used as electrical insulation between the copper segments and the steel parts. The most common angles for these commutators are 3 degrees on the outer angle and 30 degrees on the inner angle.

One of the advantages of a v-bound commutator is that it can be taken apart to replace copper, replace mica v-rings or obvious electrical problems easier than other styles. Depending on the design of the unit, some v-bound commutators can be re-insulated. This involves repairing the mica segments between the copper bars, replacing the mica v-rings, and re-using the copper bars.

glassband commutator

Glass Banded Commutators

Glass band commutators are named for the glass bands that are used to retain the copper bars and mica segments. The bands are applied in two or more grooves that have been machined into the outer diameter of the copper bars. The glass bands consist of an electrical grade tape comprised of high tensile strength parallel glass yarns bonded with thermosetting resins. The tape is applied under tension and cured in an oven.

The main advantage to using a glass banded commutator is that a bounded glass commutator can be retained in multiple locations over the entire length of the commutator bar. This results in higher stability for units with longer bars as compared to v-bound commutators that only retain on each end of the bar. Some other advantages to going with glass banded commutators over v-bound commutators are:

  • Glass band commutators are lighter than a comparable v-bound unit because less steel is required
  • Depending on the design of the steel barrel, a glass band commutator can fit into a smaller profile than a v-bound commutator
  • Glass band commutators with copper bars are less likely to be moved or damaged by a bump due to the inner diameter support by the barrel and barrel insulation

external shrink ring commutator
internal shrink ring commutator

Shrink Ring Commutators

Steel shrink ring commutators are named for the steel rings that are used to retain the copper bar and segment mica pack. They are sometimes called Dynamometer or Exciter commutators which refer to how the commutator is used. There are two primary types of shrink ring commutators that are used for different reasons, external shrink rings and internal shrink rings. Both styles rely on the interference fit on the inner diameter of the steel rings to maintain the stability of the copper bars and mica segment packs.

External Shrink Ring Commutator

External shrink ring commutators are used for applications that require extremely high RPMs. This results in stress values that would be too high for other commutator designs. This style is more expensive than v-bound or glass band commutators due to the higher material costs and the additional labor required to assemble.

Internal Shrink Ring Commutator

Internal shrink ring commutators also utilize high strength forged ring material to retain the segment pack, are more expensive than v-bound or glass band units, and is very difficult if not impossible to take it apart to replace insulation or clear any internal shorts. Due to lower cost and ease of repair, many internal shrink ring commutators are converted to the v-bound style.

Electric Materials is the trusted company for exceptional quality, performance, longevity, mechanical, and electrical integrity to manufacture your product from start to finish.

Commutator Rebuilding and Refilling Services

Electric Materials also specializes in the rebuilding and refilling of existing commutators. Units are disassembled and rebuilt with new copper using the same quality assurance processes applied to new commutators. Whether it is a commutator repair or collector rings, we assure you it will be right the first time, on time, every time. Our extensive database of commutator specifications and history ensures that your unit is rebuilt to meet the operational demands of the final application.

For Additional Information on Our Custom Commutator Production Capabilities, Please Review Our Online Commutator Quote Form