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Vespel® CR-6100 throat bushing for multi-stage horizontal pump

A throat bushing in a centrifugal pump isolates the mechanical seal environment from the overall flow within the pump. By changing the clearance at the throat bushing, pressure in the seal chamber and seal flush flow rate can be manipulated to provide a better sealing environment.
Boulden composite close clearance throat bushings create a non-metallic interface, providing increased durability, impact resistance, and thermal shock resistance. When combined with Vespel® CR-6100 or B-Series composite wear rings, our composite pump throat bushings are designed to extend the working life of your centrifugal pump.
Contact us for more information regarding our Vespel® CR-6100 or B-Series close clearance throat bushing options or call us at 800-523-0569 and we will gladly assist you with your questions. Boulden is your trusted source for state-of-the-art composite centrifugal pump components.

Throttle Bushing

Why Use Vespel® CR-6100 or B-Series for throat bushings?

Several API 682 seal flush plans require close-clearance throat bushings to function properly. Many of these designs rely on “floating” spring-positioned carbon bushings. DuPont™ Vespel® CR-6100 and Boulden B-Series composite materials are ideal materials for throat bushings and an effective replacement for carbon. They are durable, impact-resistant, and thermal shock-resistant materials that are easy to machine. Vespel® CR-6100 has a low wear rate for long working life in any application. And, because the material is non-seizing, solid Vespel® bushings can be used in place of floating carbon bushings.

Vespel® CR-6100 or B-Series Throat Bushing Advantages

Composite throat bushings provide numerous advantages over throat bushings manufactured from standard materials. Some of the greatest benefits that composite throat bushings can provide your centrifugal pump include:

  • Low wear
  • Impact and thermal shock resistant
  • Easy to machine and install
  • Ability to run with close clearances

How to Get the Most Out of Your Throat Bushings

Getting the most out of your throat bushings is out top priority. That is why we provide Vespel® or B-Series composite throat bushings. These crucial centrifugal pump components help to extend the life of your pump. The following guidelines will allow you to get the most out of your throat bushings.

  • Replace the existing throat bushing material with Vespel® CR-6100 or B-Series
  • Use the clearance recommended by the mechanical seal manufacturer for your flush plan

Close-Clearance Throat Bushings for Mechanical Seal Flush Plans

Many mechanical seal flush plans use a “close-clearance” throat bushing to provide a more efficient sealing environment. For example:

  • Plans 11 & 14 use a close-clearance throat bushing to build pressure in seal chambers
  • Plans 21 & 23 use close-clearance throat bushings to isolate cooled fluid from hot process liquids
  • Plan 32 uses a close-clearance throat bushing to isolate clean external flushes from dirty or corrosive process fluids

Composite Material Case Studies

The use of composite materials in centrifugal pumps increases the chance of a pump surviving run-dry or off-design conditions that could cause metal components to seize. The second benefit is that Vespel® CR-6100 or B-Series composite materials can be installed with reduced clearances compared to the API standard, which improves pump reliability and efficiency. Look over our Case Studies for more information on the benefits of Vespel® CR-6100 or B-Series composite materials.

Contact Boulden to Upgrade your Pump Throat Bushings to Composite Materials Today

Contact Boulden with your application details to upgrade your pump close clearance throat bushings to Dupont Vespel® CR-6100 or Boulden B-835 composite materials today. We have the composite materials you need in stock and ready for immediate shipment. If you would like to know more about the composite materials we offer and applications, sign up for our newsletter!

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