Case Study: Style 204 Expansion Joint w/ GUARDIAN® FEP Liner – Paper Mill

Garlock Style 204 Rubber Expansion Joint

picture of style 204The Style 204 family of spool-type expansion joints are manufactured with the industry standard narrow arch design. This style is intended to be used in dynamic conditions where both pressure and vacuum concerns are present.

Features and Benefits

  • Fully laboratory and field tested for long life and exceptional reliability
  • High pressure and vacuum resistance offer increased safety and ensure suitability for a wide range of applications
  • Single and multi-arch designs are available for a range of movement capabilities
  • Concentric and eccentric reducing configurations can be provided to join piping of unequal diameters
  • Available in a variety of elastomers and fabric combinations to meet the varied demands of temperature, pressure, and media

picture of paper mill

INDUSTRY

Pulp and Paper

CUSTOMER

Large South Eastern Paper Mill

BACKGROUND

A U.S. paper mill experienced multiple failures of expansion joints on the knotter screen pumps in the fiber area of the plant. The failures caused significant downtime and posed a safety hazard to employees working in the area.

OPERATING CONDITIONS

  • Size- 24”ID (DN600)
  • Temperature- Less than 250°F (120°C)
  • Application- Knotter screen feed pump
  • Media- Black liquor with wood fiber
  • Pressure- Less than 65 psi (4.5bar)

CHALLENGES FACED

A field survey determined that the expansion joints were experiencing significant elongation during installation. It was also evident that the pump and pipe flanges were not in parallel, creating angular misalignment. Additionally, the expansion joints were handling an aggressive media of black liquor and wood fibers, which collectively contributed to the failure.

SOLUTION AND BENEFITS

Through on-site troubleshooting and surveying of the expansion joints, engineers were able to recommend and design an adapter plate for the pump flanges to realign the pump to the piping. This allowed the plant to standardize the replacement expansion joints to Style 204 with GUARDIAN® FEP liner to be used in multiple locations. In addition, the mechanical bond of the GUARDIAN® FEP liner provided greater reliability than the adhesive bond of competitive PTFE lined expansion joints. Replacement cost and frequency has been significantly reduced as a result of this engineered solution.


The original case study can be found on Garlock’s website here.

Gallagher Fluid Seals is an authorized distributor of Garlock. For questions about products or to learn more about rubber expansion joints, contact our engineering department.