U.S. Bellows designed and manufactured a 64” diameter custom elbow pressure balanced expansion joint for an exhaust duct in a power plant in Alberta, Canada. It is 386” in overall length and is fabricated from carbon steel with 321 stainless steel bellows. This expansion joint is designed for 1-1/8” axial movement, ½” lateral movement at 482°F and 174 psig. Tests performed on the unit include 100% dye penetrant, x-ray, and ultrasonic on pressure bearing welds. The unit was also hydrotested at 291 psig prior to shipment.
These single expansion joints are 20″ in overall length and range in diameter from 3″ to 56″. They are composed of 321 stainless steel bellows, 316L flanges and angles, and include carbon steel covers. The expansion joints were designed for 194°F at 22 PSIG and were dye penetrant examined and soap and air tested prior to shipping to Peru.
Tie rods are necessary in some applications to continuously restrain the full pressure thrust during normal operation while permitting only lateral deflection. Here is an example of what can happen when tie rods are not specified or the piping has not been anchored.
This refractory lined expansion joint is composed of 321 stainless steel bellows and A588-A Corten angle flanges. It is lined with a 4″ thick refractory lining and measures 7′-2″ x 4′-6″ x 134″ F-F. The expansion joint was dye penetrant tested and will be utilized in flue gas service associated with a clean fuels project at an oil refinery.
U.S. Bellows custom designed tied universal expansion joints with 304 stainless steel bellows from 2″ to 18″ diameter for a chemical plant in Texas. The expansion joints are designed for 3″ lateral movement at 122°F and 100 psig. The expansion joints were hydro-tested at 150 psig and delivered in six weeks.
U.S. Bellows refurbished a 54″ dia. custom crossover expansion joint for a power plant in Kansas. The flow end and balancing end bellows were replaced. The pressure balanced expansion joint was designed for 1″ axial movement at 700°F and 150 psig. The bellows longitudinal weld seams were 100% x-rayed and the assembly was hydro-tested at 180 psig prior to shipment. The refurbishment was completed in three weeks to meet the customer’s outage requirements.
Splicing of fabric expansion joints is a critical operation which needs to be performed correctly for the expansion joint splice to hold up under system operating conditions. ensureAsplice is the answer to assure that a splice is made correctly.
U.S. Bellows material is a thin, flexible, lightweight, PTFE material that clearly indicates when the proper conditions have been established for achieving a successful test splice on FLEXXCEL Fabric Expansion Joint materials. The U.S. Bellows material accomplishes this in two ways. First, a dramatic color change in the product during the splicing procedure ensures that the critical sealing temperature has been reached in the splice area. In addition, the material bonds to the expansion joint’s PTFE surface, confirming that sufficient pressure was applied during the splicing operation.
The sealing process requires that all splice components be assembled between the heat sealer and the product. As the splice heats up, the U.S. Bellows product changes from a light shade of red to a much darker shade of the red. The easily observed color change can only take place after the splice components have reached the critical sealing temperature required for PTFE products. If sufficient pressure has been applied as the color change occurs, the product will adhere to the expansion joint’s PTFE surface, confirming that the proper splicing conditions were achieved.
A successfully completed test splice utilizing the ensureAsplice material will ensure that the variables that exist during a field splice have been accounted for. The actual splice on the expansion joint can now be completed with confidence.
Variables to consider:
- Ambient conditions
- Length of extension cord
- Acceptable voltage
- Proper “backer board” usage
- Heat Seal Iron in good working condition
- Allow iron time to reach required temperature
- Be sure the green light is illuminated
- Proper amount of time used to splice
- Proper amount of pressure applied during splice
- Follow U.S. Bellows splice procedures
Shown are the items required to produce a test splice with the product
(Heat seal iron, backer board, FLEXXCEL belting material, PFA heat sealing film, ensureAsplice product, stapler, scissors, blade knife, tape measurer, marking pen)
2. Begin by placing the product on the “Backer Board” surface.
3. Overlap the 2 pieces of FLEXXCEL belt material. The overlap should be the same width as the PFA Film. Make sure the PFA film is residing between the two belt ends in the overlap splice area. Staple the PFA Film in place.
View the full instructions at: http://www.usbellows.com/fabric-catalog/ensureasplice.html
These universal metallic expansion joints were custom designed for a pipe line in a bioengergy plant. They range from 20″ to 30″ in diameter, and are designed for 2″ lateral movement with a 1,362 lb/in. spring rate. The expansion joints are fabricated entirely from 304 stainless steel and designed for 250°F and 30 psig. Each unit was 100% dye penetrant examined and air tested prior to shipment.
U.S. Bellows custom designed 14″ dia. and 84″ dia. single expansion joints for a pipe line in an utility plant in Colorado. The bellows are 304 stainless steel and carbon steel was used for the flanges and tie rods. The assemblies were designed for a spring rate of 2,530 lb/in., 1″ axial movement at 300°F and 37 psig. The assemblies were dye penetrant examined and air tested with a delivery of 12 weeks.
Our field service team is available 24/7 during your plant turnaround!
- Our team can assist with plant walk-downs to assess your plant for maintenance, repair or replacement of expansion joints and pipe supports
- Our engineers are available day or night for guidance on placement, materials, finishes, etc.
- Our field service team will guide you through installation, start-up, and replacement
- We stock over 1500 bellows, over 100,000 lb. of insulation materials, over 30,000 spring coils, and over 1 million pounds of standard items
- Afterwards, receive training to monitor, identify potential failure, learn correct size and selection of expansion joints and pipe supports per application
- We can develop a data book of existing pipe supports and expansion joints and their conditions in order to identify potential maintenance issues in upcoming turnarounds.
View Some of Our Emergency Projects
This expansion joint received in the morning and shipped to the customer the very same day.
Same day delivery enabled the customer to resume operations with minimum loss of time and production.
Quick Turnaround of Refurbished Expansion Joint
A service call came in when a leak was discovered resulting from a crack in the bellows of a pressure balanced elbow expansion joint. New bellows were fabricated, carbon steel root rings and cover bolts were replaced, and the unit was back in service in high pressure turbine crossover piping within a few weeks.