garlock sealing technologies
- February 02, 2024
Corrosion with Braided Packing
Galvanic corrosion is an electrochemical process that occurs between two dissimilar metals, or between a metal and a conductive non-metallic material, when both are exposed to an electrically conductive media. In the case of a packing gland, it occurs between a metal component and the carbon or graphite packing. Under these conditions, the material that is closest to the anodic end of the galvanic scale will be corroded in preference to the one that is closest to the cathodic end of the scale. (See Table 1.) As the distance between materials on the galvanic scale increases, a corresponding rise occurs in the rate and the extent of the corrosion.
In a valve or a pump using packing made of either graphite or carbon, a galvanic reaction may be initiated as soon as any electrically conductive fluid, such as water, is introduced. Since graphite is more cathodic than the metals that make up valves and pumps, it is the metal that may
- October 27, 2023
Abrasive media comes in many forms—from mining slurries to wood pulp and even substances as seemingly mild as liquid chocolate. This diversity rules out a one-size-fits-all solution for abrasive pumping applications. However, today’s broad range of materials, from carbon fiber packing to graphite-filled polytetrafluoroethylene (PTFE) bushings, includes products capable of meeting an equally broad range of abrasive wear requirements.
Carbon Fiber Packing
Few materials offer the abrasive resistance and heat dissipation of carbon fiber yarns. Braided compression packing made from this material excels under extreme conditions, including exposure to a variety of chemicals, temperatures approaching 850 F (454 C) in oxygen-rich atmospheres (up to 1,200 F/649 C in steam) and shaft speeds in excess of 4,000 feet per minute (fpm).
- May 07, 2021
During an initial expansion joint Preventative Maintenance and Reliability (PMR) Service performed at the paper mill, it was determined that several competitor joints required replacement. These pipelines carry water, pulp, black/white liquor, bleach, and CIO2.
Though recommended for replacement on the Garlock Preventative Maintenance and Reliability (PMR) report, the mill postponed purchase. To date, four of those items flagged for replacement have failed - with the most recent failure resulting in an administration building filling with 4 feet of pulp.
OPERATING CONDITIONS AT CUSTOMER FACILITY
- Size: Pipe- 1.5” - 48” ID
- Temperature: 70° - 250°F
- Application: Various throughout mill
- Media: Various throughout mill
- Pressure: Vacuum to 200psi