Vespel

For the past two decades, pump users have had remarkable success upgrading critically important process pumps with Vespel®, a composite material made with Teflon and long carbon fibers (see reference note). In 2016 and 2017, the Boulden Comany (Conshohocken, Pennsylvania, and Ellange, Luxembourg) completed publishing an informative series of guidelines on upgrading pumps with  DuPont™ Vespel® CR-6100. The Boulden company’s releases delved into details on how to upgrade various horizontal and vertical pump types. They discussed reducing the clearance of the wear rings, upgrading throttle bushings with their innovative PERF-Seal™ design, and upgrading vertically suspended pump shaft bearings.

A FRESH LOOK

The company followed up by condensing their many application bulletins into a short list of guidelines which they (or you, the user) can apply to just about any pump. Following these rules gives user-purchasers confidence that they are using Vespel® CR-6100 properly and thereby improve pump reliability without compromise.

The users of Vespel® CR-6100 and the PERF-Seal™ design have developed many innovative applications. Figures 1 and 2 are among the more recent ones. Figure 1 depicts the center stage of a two-stage double suction/double suction kerosene pump. This pump was upgraded with both Vespel® CR-6100 and the PERF-Seal™ design. Figure 2 is the center stage of a 3 MW boiler feed water pump upgraded with Vespel® CR-6100 and the PERF-Seal™ design.


Featured: The center stage of a two-stage double suction/double suction kerosene pump. This pump was upgraded with both Vespel® CR-6100 and the PERF-Seal™ design.
Above: Center stage of a 3 MW boiler feed water pump upgraded with Vespel® CR-6100 and the PERF-Seal™ design.
Seven Rules For Using DuPont™ Vespel® CR-6100

  1. Stay under the temperature limit of 500 degrees Fahrenheit (260 degrees Celsius).
  2. Use only in stationary parts, mounted in compression.
  3. Shoulder on the low-pressure side to retain the part against elevated differential pressure.
  4. Avoid extremely abrasive services such as slurries, bottoms, or slops.
  5. Press fit, clearance, and axial length of part comply with the Boulden Installation Guide.
  6. Pump rotor must turn freely when the pump is assembled and ready for commissioning.
  7. Use PERF-Seal™ design for throttle and center bushings of multi-stage pumps
    (see reference note).

 

WHAT DO YOU THINK?

Boulden invites users to share their findings and applications with the Boulden company and its worldwide customers. Let them know if the above “Seven Rules” missed anything and freely explain your ideas. Make liberal use of the company’s application engineering offers and use its literature as guideline and detailed procedures. When working with a third-party pump rebuilder, ascertain the rebuilder will do more than just repair. Let the rebuilder upgrade your fluid machine assets by capturing the many advantages enjoyed by forward-looking users of the mature products that are the subject of this brief article.

For details on how to install Vespel® CR-6100 into nearly any pump type, download the Boulden Installation Guide. If you need material, they carry a huge inventory of standard stock sizes; all are available for immediate shipment from several locations around the globe.

 

REFERENCE
Bloch, Heinz P., “Petrochemical Machinery Insights,” (2016) Elsevier Publishing, Oxford, UK, and Cambridge, MA.

 

Heinz P. Bloch resides in Westminster, Colorado. His professional career commenced in 1962 and included long-term assignments as Exxon Chemical’s regional machinery specialist for the United States. He has authored or co-written over 700 publications, among them twenty comprehensive books on practical machinery management, failure analysis, failure avoidance, compressors, steam turbines, pumps, oil mist lubrication, and practical lubrication for industry.  Mr. Bloch holds B.S. and M.S. degrees (cum laude) in mechanical engineering.  He is an ASME Life Fellow and was awarded life-time registration as a Professional Engineer in New Jersey. He can be reached at heinzpbloch@gmail.com. Robert Aronen is the world-wide marketing manager for Boulden products. After a fruitful career as a machinery engineer for a refinery in California, he is now responsible for innovative applications of the company’s PERF® bushings and other components that have allowed equipment users to improve both operating life and rotating machinery efficiency. These endeavors inevitably translate into downtime avoidance and significantly enhanced plant safety. He can be reached at robert@bouldencompany.com.

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MODERN PUMPING TODAY, March 2018
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