Equatemp® Sprue Bushings

Equatemp® Sprue Bushings

The genesis of MDI was the development and patenting of the integrally heated Equatemp® Hot Sprue Bushing. MDI recognized by developing a robust integrally heated hot sprue bushing this would provide the customer with the ultimate temperature control and uniformity and address several variables that contribute to premature heater failure.

Equatemp® Sprue Bushing Features

  • High purity ceramic insulator compacted to its near theoretical limits insures highest heat transfer rate, resulting in longer heater life
  • Predetermined wattage distribution, provides even heat along its entire body resulting in better melt flow
  • Air Gaps machined around its head and body eliminate secondary machining operations on molds
  • Optional extra stock at the end of the bushing allows for custom machining
  • A replaceable thermocouple can be inserted into a provided thermowell and is located at the tip or in any other desired location for a more accurate melt temperature reading
  • Independent dual zone bushings are available for processing sensitive resins, or for other special applications
  • Constructed out of H-13 tool steel
  • Heat treated up to 35Rc

The flexibility in the design insures an answer to any of your special needs

Equatemp® Sprue Bushings

Equatemp® bushings are offered in two styles. The MB Series has the solid piece design, while the RB series offers the replaceable tip design.


Single Body Style

The MB Series is available with optional extra stock allowing custom machining.

Replaceable Tip Body Style

The RB series offers the sprue bushing body with replaceable tips in three different configurations


Topless Tip

The most common tip which is designed for excellent cosmetic gates

Rb10T

Full Body

The gate geometry is machined in the end cap while allowing good gate vestige

Rb10F

Sprue Type

A replaceable tip for feeding runners

Rb10S

Hot Runner Systems made in U.S.A

MDi is a world-leading American manufacturer of Hot Runner systems and components with the capability to develop custom and innovative solutions for plastics Injection Molding. Established in 1984, MDi continues to offer experience in the design and manufacturing of complete, internally heated and balanced precision Hot Runner systems, Valve Gate systems, Sprue Bushings, Molding Machine nozzles, Filters, and MDi's unique system products and controls. All of our components are in-house designed and manufactured in our facility at St. Charles, IL, with a focus on quality and reliability.