U.S. Bellows designed and fabricated tied universal expansion joints and single hinged expansion joints for a power plant in Canada. All the units were fabricated from carbon steel with 316 stainless steel bellows. The universal tied joints are 102″ diameter, 225″ long and are designed for 8.2″ lateral movement. The hinged joints are 102″ diameter, 71″ long and designed for 0.76° angular rotation. Each expansion joint can withstand temperatures up to 250°F at 7.25 psig. The bellows and pipe long seams were 100% x-rayed, and all the welds were 100% dye penetrant tested. A soap and air test was performed prior to shipment.
Single Expansion Joints > Blog Articles
This 48-3/4″ diameter single metallic expansion joint will be used in a heat exchanger. The bellows are 321 stainless steel and the pipe is 304 L stainless steel. This expansion joint is rated for 145 psi with 1″ compression and temperatures up to 600°F. The unit was 100% x-ray tested, hydro-tested and 100% dye penetrant tested.
The single expansion joint is simply a bellows element with end connections. Regardless of accessories, such as liners and covers, it will deflect in any direction or plane that the bellows will. It is the least expensive type, but requires that the piping be controlled as to the direction of the movements required of the unit. The expansion joint should not be expected to control the movement of the pipe. If the piping analysis shows that the expansion joint must accept axial compression, then the piping must be guided and constrained so that only that movement will occur.
This expansion joint will not resist any deflections with any force other than the resistance of the bellows, which is a function of the spring rate times the deflection amount. It is incapable of resisting the pressure thrust along its axis, which is the product of the pressure times the effective, or cross sectional, area of the bellows. Large diameter units, even with low pressures, can generate very large axial pressure thrust forces, which must be reacted by main and directional anchors. Otherwise the expansion joint will extend with disastrous results.
Projects Including Single Expansion Joints:
Single Tied Expansion Joints for a Pipeline in Alaska
The expansion joint assemblies are fabricated entirely from stainless steel with a design pressure of 50 PSIG. They are designed with tie rods that do not permit axial movement, but allow for lateral movement up to 1/2″. The expansion joints will be used on a process line that contains exhaust gas and hydrocarbon vapor at a low concentration. It will connect an oil tank with a vapor control system.
The expansion joint assemblies are fabricated for a 12″ pipe and are designed for 2-1/2″ lateral movement. The design pressure is 276 PSIG with a design temperature of 626°F. 316L stainless steel was used for the bellows and tie rods. The expansion joints include 300 lb. raised face stainless steel flanges to accommodate low spring rate requirements.
Hinged Expansion Joints with Refractory Lining
Hinges cause the unit to bend in a single plane. The hinge mechanism is designed to accept the full pressure thrust.
- Design Pressure: 75.4 PSIG
- Design Temperature: 1400°F
- 100% X-ray Tested
- Pneumatically Tested weld seams to 83 PSIG
Elbow Pressure Balanced Expansion Joints
The expansion joints are fabricated for a 36″ pipe and are designed with Inconel® 625 grade LCF bellows. They include a liner provided with drain holes to prevent accumulation of corrosive condensation.
Inline Pressure Balanced Expansion Joints
- Design: 125 PSIG, Temperature: 244°F
- 304 SS Bellows, Flanges & Liners
- Designed to Balance 48,000 lb. of Pressure Thrust
Externally Pressurized Expansion Joints
These expansion joints are fabricated for a piping system in a steam plant. They include 304 SS bellows and carbon steel shell and flanges, and are designed for 150 PSIG and 350°F.
These expansion joints are designed for a 55″ diameter overhead vapor line at a refinery. The overall length is 310″ and the bellows are fabricated from 625 LCF. The expansion joint is designed for 50 PSIG and 1075°F.
The single flanged metallic expansion joint was manufactured from 304 stainless steel bellows with carbon steel flanges. It has a diameter of 20″ and an overall length of 15″. It will be used in an exhaust duct application in a power plant. A hydro-test was performed prior to shipping to Orlando, Florida.
U.S. Bellows, Inc. fabricated several expansion joints composed of 321 stainless steel and A588-A Corten angle flanges. The expansion joints measure 76″ in diameter and have an overall length of 27¾”. Each expansion joint is also lined with 4″ thick refractory lining.
The bellows long seams were 100% x-rayed and dye-penetrant tested. The bellows will be used in flue gas service associated with a clean fuels project at an oil refinery.
U.S. Bellows, Inc. received this single expansion joint in the morning, refurbished it, and shipped it to the customer the very same day. The expansion joint bellows, liner, and cover were replaced. The carbon steel parts were sand blasted, cleaned and painted. The expansion joint was 4″ I.D. x 16 3/4″ face-to-face. The design conditions of the expansion joint were 345 PSI at 500F. The expansion joint was 100% dye-penetrant examined and hydro-tested to 518 PSIG prior to being shipped back to a local area refinery.
U.S. Bellows, Inc. received this single expansion joint in the morning, refurbished it by adding new bellows and limit rods, and then shipped it the very same day. The existing expansion joint had 321 stainless steel bellows with 1,500 lb. flange on one side and 150 lb. flange on the other side. U.S. Bellows, Inc. manufactured new 321 stainless steel bellows and reused the existing flanges by sandblasting and then painting them for protection. Same day delivery enabled the customer to resume operations with minimum loss of time and production.
U.S. Bellows, Inc. designed and fabricated single tied expansion joints for a pipeline in Alaska. The 12″ diameter expansion joints had an overall length of 12″ and the 24″ diameter expansion joint had an overall length of 14 1/2″.
The expansion joint assemblies are fabricated entirely from stainless steel. The design pressure of the expansion joints was 50 PSIG. They are designed with tie rods that do not permit axial movement, but allow for lateral movement up to 1/2″. The expansion joints will be used on a process line that contains exhaust gas and hydrocarbon vapor at a low concentration. It will connect an oil tank with a vapor control system. The expansion joints were 100% dye-penetrant tested and hydro-tested to ensure quality control.