Twenty-four single hinged expansion joint were custom designed for a chemical plant. Eight are 16″ dia., four are 12″ dia., twelve are 6″ dia., and they range in length from 14″ to 16″. The bellows are fabricated from 304 stainless steel and the rest is carbon steel. The 16″ dia. joints are designed for 2° Angular movement at 300°F and 150 psig. The 12″ dia. joints are designed for 1 deg. Angular movement at 300°F and 400 psig. The 6″ dia. joints are designed for 1° angular movement at 300°F and 650 psig. All expansion joints were dye penetrant examined and hydro-tested prior to shipment.
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62″ Fabric, 42″ Hinged and 42″ Tied Universal Expansion Joints and Duct Work Designed for an Acid Plant
U.S. Bellows custom designed two 42″ tied universal expansion joints, a 42″ hinged expansion joint and a 62″ fabric expansion joint in ductwork for an acid plant in Louisiana. The assemblies had flanged and flued head bellows fabricated from 304H stainless steel. The rest of the assemblies were made from carbon steel with operating temperatures of 700°F at 10 psig. The expansion joints were dye penetrant and x-ray tested prior to shipment.
Within a two week deadline, U.S. Bellows refurbished a 59-1/4″ diameter single hinged expansion joint for a refinery in Louisiana. The expansion joint is 119-3/4″ in overall length and designed for .82″ angular rotation at 1380°F and 35 psig. The bellows are fabricated from Inconel 625 LCF, and the entire assembly is 304H stainless steel. Before shipment, the bellows were x-rayed and the assembly was 100% dye penetrant and air tested to 52 psig.
U.S. Bellows designed a 102″ dia. single hinged expansion joint and duct work assembly, along with two 92″ single expansion joints for a coal gasification facility in Mississippi. Both the assembly and expansion joints were fabricated from carbon steel with 304 stainless steel bellows, and designed for 3.6° angular movement at 825°F and 3 psig. The expansion joints were dye penetrant examined, 100% x-rayed and soap and air tested prior to shipment.
U.S. Bellows provided the total engineering, design and fabrication package for this project that included: expansion joints, elbows, duct work, saddle supports, F-type variable spring supports, slide plates and pipe anchors.
A total of twelve, 119″ dia. double slotted hinged expansion joints, thirty-six, 72″ dia. elbows and twelve, 119″ dia., 55′ long header ducts were fabricated for a power plant in Mississippi. The expansion joint assemblies were designed for .5° angular movement, 3/8″ lateral, 1-1/2″ axial compression. The design conditions were 5 psig at 300°F. The duct work was fabricated from A-36 carbon steel material and the bellows were fabricated from 304 stainless steel. A dye penetrant exam, soap and air test and spot x-ray on all duct seam welds was performed prior to shipping.
Hinged Universal Expansion Joint and Duct Work Assembly Custom Designed for an Exhaust Duct Application
This week’s featured product is on a hinged universal expansion joint and duct work assembly custom designed for an exhaust duct application in a power plant in Kenya. The hinge hardware was fabricated from carbon steel, while the rest of the unit was fabricated from 316 stainless steel with Inconel 625 bellows. An F-type variable spring was also provided for this project and will be used to support the center spool between the two elbows. The duct work with expansion joint is 36″ in diameter and the distance between the centerline of the two 90 degree elbows is 240″. It is designed for 20 psig at 115°F and 1/2 degree of angular movement. The entire assembly was 100% dye penetrant tested and a soap and air test was performed prior to shipment.
U.S. Bellows, Inc. designed a double hinged reinforced expansion joint for a 92″ diameter pipe in a water treatment plant located in Canada. The bellows, root rings and collars are fabricated from 321 stainless steel. The weld ends and hinge hardware are fabricated from carbon steel. This expansion joint was designed for 100 PSIG at 300°F with 4° angular movement for each bellows. The bellows long seams and longitudinal pipe welds were 100% x-ray examined, and a hydro-test at 150 PSIG, along with a 100% dye penetrant test for all welds was performed prior to shipment.
This single hinged expansion joint is designed for sulphur dioxide service in a sulphuric acid plant. It was fabricated with 321 stainless steel bellows and liner, and A-516 GR 70 carbon steel hinge plates and pipe. The pipe is 66″ outside diameter and 35-1/4″ overall length. The expansion joint was designed for 6° angular and 3 PSIG at 680°F. The bellows and pipe long seams were 100% x-rayed, and all the welds were 100% dye penetrant tested. A soap and air test at 15 PSIG was conducted prior to shipment.
Hinges permit angular rotation in one plane only by the use of a pair of pins through hinge plates attached to the expansion joint ends. Hinges and hinge pins are designed to restrain the thrust of the expansion joint due to internal pressure. Hinges can also be designed to carry piping loads, if specified.
Features of hinged expansion joints include:
- Angular rotation in one plane
- Eliminates pressure thrust forces
- Transmits external loads
- Prevents torsion on bellows
- No main anchors required
- Minimum guiding required
- Low forces on piping system
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.
U.S. Bellows, Inc. designed and fabricated two 44″ hinged expansion joints with 5″ thick refractory lining. These expansion joints are part of FCC stand-pipes in a synfuels plant. Each expansion joint is fabricated of two-ply Inconel® bellows and 3/4″ wall pipe. The joints consist of 2″ thick attachment rings. After fabrication, the expansion joints were pneumatically tested and inter-plies tested. The bellows and pipes were 100% x-rayed and PMI tested.
Thermal and structural Finite Element Analysis (FEA) was performed on the expansion joints to ensure the product is structurally sound and determining the thermal profile helps to prevent polythionic corrosion on the bellows. Design calculations were performed for all hardware including lug rings, gussets, hinge plates, pins, etc.