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.
The two assemblies shown, a mitered elbow duct work and fabric expansion joint and duct work assembly, are designed for a sulfuric acid plant. Both assemblies are fabricated from 1/4" thick 304L stainless steel. They are designed for a 15" water column with a temperature of 180°F, axial compression of 3/4", and lateral movement of 3/4". A dye penetrant examination is performed on all welds prior to shipment.
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.
This universal flanged and flued head expansion joint and duct work assembly is designed for a 90″ diameter line. It includes slotted hinge plates installed across the bellows to carry the weight of the duct between the bellows and equalize the axial compression between the two bellows. The flanged and flued heads, duct and weld ends are fabricated from 304 H stainless steel. The expansion joint is designed for 2″ axial compression, 2-1/2″ lateral deflection, and 1150°F at 5 PSIG. A spot x-ray test, soap and air test, and 100% dye penetrant exam were performed prior to shipment.
U.S. Bellows provides custom designed expansion joints in duct work and fabricated duct work assemblies. The assemblies may include fabricated elbows, tees, and straight sections of duct work, in carbon steel or stainless steel, and in diameters of 42″ or larger. The duct sections can include fabric or metallic expansion joints and can be rectangular or round. U.S. Bellows can also provide specialized pipe supports and spring hangers for large diameter duct work. Additionally, we offer complete pipe stress analysis of your duct systems using CAESAR II software.
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This duct work was fabricated with mitered elbows from SA-516 grade 70 carbon steel, and was designed for absorbing tower piping in an acid plant. It has a 72″ outside diameter and measures 23′-2/4″ from the centerline, elbow to elbow. This assembly was only a single portion of a duct work system that included 36″, 48″ and 60″ diameter sections of fabricated duct work. The duct work was fabricated with roundness tolerance of +/- 1/8″. A 100% dye penetrant test, soap and air test, and spot x-ray testing of all pipe circumferential and long seam welds was performed prior to shipment.
U.S. Bellows designed and fabricated a 78″ fabric expansion joint and duct work assembly with a 90° elbow for a sulphuric acid plant in Louisiana. A stress anaylsis was performed to determine thermal movements and spring supports, loads and travel.
The ducts are fabricated from carbon steel and are 30′ long. The expansion joint is designed for 750°F at 5 PSIG with 2.5″ lateral deflection (cold preset) and 2″ axial compression. Cradle supports and a “big ton” spring support were also fabricated for this project.
Tied Universal Expansion Joint with a 45 Degree Mitered Elbow for a Flue Gas System in an Oil Refinery
This tied universal expansion joint with a 45 degree mitered elbow will be installed in a flue gas system. The assembly is 60″ in diameter and 215″ long. The pipe is fabricated from A 516 GR 70 carbon steel and the bellows are Inconel® 625 LCF. The bellows were 100% x-rayed and hydro-tested to 15 PSIG prior to shipping.
60 Inch Ductwork with Spring Supports, Snubbers, a Support Cradle and a Fabric Expansion Joint for a Sulfuric Acid Plant in Texas
U.S. Bellows, Inc. and PT&P combined to furnish a fabric expansion joint, duct work, a spring support cradle and snubbers. US Bellows furnished a fabric expansion joint with acid resisting fabric and also a duct work measuring 34’ long and 60” in diameter which was fabricated from ASTM A 516GR 70 carbon steel. PT&P furnished spring supports, carbon steel cradle supports, and snubbers. The expansion joint was completed within 6 weeks in time for a plant shutdown. A computerized pipe stress analysis, utilizing the Caesar II stress program, was performed to obtain the forces and moments imposed on the equipment nozzles and weights to be carried by the spring supports.