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Tag: Externally Pressurized Expansion Joints
Type:
Externally Pressurized Expansion Joint
Size:
133 11/16″ and 120.5″ Long | Both Have 42″ Pipe Dia.
Design:
Inconel 625 | Carbon Steel
Material:
450°F at 108 PSIG & 31″ and 25″ Axial Compression
Testing:
Hydro-tested at 167, PMI, 100% X-Ray, and Dye-Penetrant
US Bellows custom-designed these externally pressurized expansion joints for a flare header application at a refinery in Mississippi. One unit measures 133-11/16″ long and the other measures 120-1/2″ long, and both are manufactured for a 42″ pipe diameter. The bellows were fabricated from Inconel 625 and used in conjunction with a carbon steel pipe per A671-CC-60 CL.22. The carbon steel pipe is finished with a 2-coat paint system for corrosion protection. They are manufactured for a design pressure of 108 psig at 450°F with 31″ and 25″ of axial compression. All alloy material was PMI inspected. The units were hydro tested at 167 PSIG, 100% dye-penetrant tested, and the bellows and pipe weld seams were 100% X-ray tested prior to shipment.
Expansion joint applications are varied depending on the type of plant. Some applications include:
Exhaust systems for aerospace, trucks, marine piping
Solid waste incineration for renewables and biofuel plants
Waste water treatment plants for municipal water districts, as well as manufacturing plants
Kilns in mining, food, and plastics plants
Geothermal plants
Gas turbines
FCC units
Heat exchangers
Steam distribution in geothermal plants
Water cooling systems for nuclear power plants, such as the inlet of condenser cooling water from lakes or large bodies of water
Thermal oxidizer systems in polymer processing
Boller duct expansions
Vacuum jacketed piping systems in LNG
We have built, supplied, installed, replaced, audited, repaired, and tested expansion joints for most piping system applications. Our in-house expertise in handling different types of materials needed for expansion joints made of carbon steel, stainless, alloy steel, high nickel alloys, and aluminum spans over our 48 years of work. Welding specialties include TIG, pulse-arc MIG, SMAW, SUB-ARC, and Aluminium. Our qualifications for expansion joints are ASME Section IX, AWS D1.1, NS, and MIL-STD-248. Testing can be specified to include any or all of the following, depending on project and application requirements:
Magnetic particle-dry method
Liquid penetrant-visible and fluorescent
Ultrasonic and radiography
Hydrostatic and pneumatic testing
US Bellows, a subsidiary of Piping Technology and Products, is a member of the EJMA association, which maintains a set of standards for quality expansion joint design and manufacturing. The standards are used as a worldwide reference for the proper selection and application of expansion joints.
133 11/16″ and 120.5″ Long | Both Have 42″ Pipe Dia.
Design:
Inconel 625 | Carbon Steel
Material:
450°F at 108 PSIG & 31″ and 25″ Axial Compression
Testing:
Hydro-tested at 167, PMI, 100% X-Ray, and Dye-Penetrant
US Bellows custom-designed these externally pressurized expansion joints for a flare header application at a refinery in Mississippi. One unit measures 133-11/16″ long and the other measures 120-1/2″ long, and both are manufactured for a 42″ pipe diameter. The bellows were fabricated from Inconel 625 and used in conjunction with a carbon steel pipe per A671-CC-60 CL.22. The carbon steel pipe is finished with a 2-coat paint system for corrosion protection. They are manufactured for a design pressure of 108 psig at 450°F with 31″ and 25″ of axial compression. All alloy material was PMI inspected. The units were hydro tested at 167 PSIG, 100% dye-penetrant tested, and the bellows and pipe weld seams were 100% X-ray tested prior to shipment.
Expansion joint applications are varied depending on the type of plant. Some applications include:
Exhaust systems for aerospace, trucks, marine piping
Solid waste incineration for renewables and biofuel plants
Waste water treatment plants for municipal water districts, as well as manufacturing plants
Kilns in mining, food, and plastics plants
Geothermal plants
Gas turbines
FCC units
Heat exchangers
Steam distribution in geothermal plants
Water cooling systems for nuclear power plants, such as the inlet of condenser cooling water from lakes or large bodies of water
Thermal oxidizer systems in polymer processing
Boller duct expansions
Vacuum jacketed piping systems in LNG
We have built, supplied, installed, replaced, audited, repaired, and tested expansion joints for most piping system applications. Our in-house expertise in handling different types of materials needed for expansion joints made of carbon steel, stainless, alloy steel, high nickel alloys, and aluminum spans over our 48 years of work. Welding specialties include TIG, pulse-arc MIG, SMAW, SUB-ARC, and Aluminium. Our qualifications for expansion joints are ASME Section IX, AWS D1.1, NS, and MIL-STD-248. Testing can be specified to include any or all of the following, depending on project and application requirements:
Magnetic particle-dry method
Liquid penetrant-visible and fluorescent
Ultrasonic and radiography
Hydrostatic and pneumatic testing
US Bellows, a subsidiary of Piping Technology and Products, is a member of the EJMA association, which maintains a set of standards for quality expansion joint design and manufacturing. The standards are used as a worldwide reference for the proper selection and application of expansion joints.
“Decarbonation” and “Carbon Neutral” are two key terms used to describe efforts to lower the amount of greenhouse gasses emitted into the atmosphere. Efforts are now underway to gradually convert existing Coal-Fired, HRSG (Heat Recovery Steam Generated or Natural Gas Powered) and other power plants utilizing fossil fuels onto plants that emit far fewer greenhouse gasses into the atmosphere. U.S. Bellows, Inc. received unique specifications to design and manufacture externally pressurized expansion joints for a facility overseas. The bellows are fabricated from 316 stainless steel and all other components are carbon steel. They are designed for a temperature of 200°F at 150 psig with 8″ axial compression. The units are 4″ NOP x 63″ L, 6″ NPS x 61.44″ L, and 12″ NPS x 64″ L.
Externally pressurized pipe expansion joints, also known as X-Flex expansion joints, are suited for piping systems that require large amounts of axial compression or extension. In externally pressurized pipe expansion joints, the bellows elements are arranged so that the media flow is on the external surface of the bellows. Externally pressurizing the bellows eliminates pressure instability as a limitation to the design and permits the absorption of large amounts of axial expansion. Our QC department conducted various NDT examinations (X-Rays, PMI, Penetrant Tests, and Hydro Tests). Also provided were “weld maps” and MTR’s for client review and inspection. At U.S. Bellows, we are constantly developing and assisting client engineers in this effort toward decarbonation by designing innovative products to accommodate new and unusual design specifications.
“Decarbonation” and “Carbon Neutral” are two key terms used to describe efforts to lower the amount of greenhouse gasses emitted into the atmosphere. Efforts are now underway to gradually convert existing Coal-Fired, HRSG (Heat Recovery Steam Generated or Natural Gas Powered) and other power plants utilizing fossil fuels onto plants that emit far fewer greenhouse gasses into the atmosphere. U.S. Bellows, Inc. received unique specifications to design and manufacture externally pressurized expansion joints for a facility overseas. The bellows are fabricated from 316 stainless steel and all other components are carbon steel. They are designed for a temperature of 200°F at 150 psig with 8″ axial compression. The units are 4″ NOP x 63″ L, 6″ NPS x 61.44″ L, and 12″ NPS x 64″ L.
Externally pressurized pipe expansion joints, also known as X-Flex expansion joints, are suited for piping systems that require large amounts of axial compression or extension. In externally pressurized pipe expansion joints, the bellows elements are arranged so that the media flow is on the external surface of the bellows. Externally pressurizing the bellows eliminates pressure instability as a limitation to the design and permits the absorption of large amounts of axial expansion. Our QC department conducted various NDT examinations (X-Rays, PMI, Penetrant Tests, and Hydro Tests). Also provided were “weld maps” and MTR’s for client review and inspection. At U.S. Bellows, we are constantly developing and assisting client engineers in this effort toward decarbonation by designing innovative products to accommodate new and unusual design specifications.
US Bellows custom-built a single-ply x-flex bellows for the world’s largest manufacturer and supplier of flooring products with locations throughout the United States. Flooring products such as carpet, ceramic tile, natural stone, laminate, vinyl, and hardwood require many of the same piping systems as traditional indoor plants in the automotive, food processing, semiconductor, textile, and pulp & paper industries. Plants that manufacture flooring are usually large, requiring large tracts of land. As a result, the “pipe runs” can extend hundreds of feet, requiring various types of expansion joints to accommodate the pipe’s movement while also relieving stresses in the piping system. Externally pressurized expansion joints are particularly well-suited for piping systems that require significant axial compression or extension. In externally pressurized pipe expansion joints, the bellows elements are arranged so that the media flow is on the external surface of the bellows. Externally pressurizing the bellows eliminates pressure instability as a limitation to the design and permits the absorption of large amounts of axial expansion. These expansion joints are fabricated with 304 stainless steel bellows, flanges, and pipe. They are designed for 300°F at 14.7 PSIG with an 8″ extension. The units are 3″ pipe x 40″ long, and 4″ pipe x 40″ long. The expansion joints were hydro-tested and underwent NDE quality control inspection tests, such as liquid penetrate inspection (LPI) before shipment.
US Bellows custom-built a single-ply x-flex bellows for the world’s largest manufacturer and supplier of flooring products with locations throughout the United States. Flooring products such as carpet, ceramic tile, natural stone, laminate, vinyl, and hardwood require many of the same piping systems as traditional indoor plants in the automotive, food processing, semiconductor, textile, and pulp & paper industries. Plants that manufacture flooring are usually large, requiring large tracts of land. As a result, the “pipe runs” can extend hundreds of feet, requiring various types of expansion joints to accommodate the pipe’s movement while also relieving stresses in the piping system. Externally pressurized expansion joints are particularly well-suited for piping systems that require significant axial compression or extension. In externally pressurized pipe expansion joints, the bellows elements are arranged so that the media flow is on the external surface of the bellows. Externally pressurizing the bellows eliminates pressure instability as a limitation to the design and permits the absorption of large amounts of axial expansion. These expansion joints are fabricated with 304 stainless steel bellows, flanges, and pipe. They are designed for 300°F at 14.7 PSIG with an 8″ extension. The units are 3″ pipe x 40″ long, and 4″ pipe x 40″ long. The expansion joints were hydro-tested and underwent NDE quality control inspection tests, such as liquid penetrate inspection (LPI) before shipment.
This externally pressurized expansion joint was designed by U.S. Bellows for a reformer unit at a refinery in Saudi Arabia. It is 59 9/16″ long with a nominal pipe size of 3″. The bellows were fabricated from 304 stainless steel and the pipe, flanges and hardware from chrome-moly. The unit is designed for an operating temperature of 1020°F at 140 psig. 11.75″ of axial compression and 1.25″ of extension. The expansion joint was 100% dye-penetrant tested, x-ray tested the bellows, and hydro-tested prior to shipment
This externally pressurized expansion joint was designed by U.S. Bellows for a reformer unit at a refinery in Saudi Arabia. It is 59 9/16″ long with a nominal pipe size of 3″. The bellows were fabricated from 304 stainless steel and the pipe, flanges and hardware from chrome-moly. The unit is designed for an operating temperature of 1020°F at 140 psig. 11.75″ of axial compression and 1.25″ of extension. The expansion joint was 100% dye-penetrant tested, x-ray tested the bellows, and hydro-tested prior to shipment
U.S. Bellows custom designed externally pressurized expansion joints for a power plant in Venezuela. The units are 56″ in overall length and have a 36″ inside diameter. The bellows are fabricated from Hastelloy C-276 and the flanges and spool are A36 carbon steel. The units are designed for an operating pressure of 60 psig at 572°F and 9.75″ of axial compression. The expansion joints were 100% dye-penetrant tested and hydro-tested prior to shipment.
U.S. Bellows custom designed externally pressurized expansion joints for a power plant in Venezuela. The units are 56″ in overall length and have a 36″ inside diameter. The bellows are fabricated from Hastelloy C-276 and the flanges and spool are A36 carbon steel. The units are designed for an operating pressure of 60 psig at 572°F and 9.75″ of axial compression. The expansion joints were 100% dye-penetrant tested and hydro-tested prior to shipment.
500°F at 30 psig, 189 lb./in. Spring Rate & 8″ Axial
Testing:
Dye-Penetrant and Air Soap & Bubble
U.S. Bellows custom designed these externally pressurized expansion joints for pneumatic conveying and filtration at a manufacturing facility in Missouri. The units were completely fabricated for 304 stainless steel. They are 4″ in diameter and 57″ in length. These expansion joints are designed for an operating temperature or 500°F at 30 psig, with a spring rate of 189 lb./in. and can absorb 8″ of axial compression. The units were 100% dye-penetrant and air soap & bubble tested prior to shipment.
500°F at 30 psig, 189 lb./in. Spring Rate & 8″ Axial
Testing:
Dye-Penetrant and Air Soap & Bubble
U.S. Bellows custom designed these externally pressurized expansion joints for pneumatic conveying and filtration at a manufacturing facility in Missouri. The units were completely fabricated for 304 stainless steel. They are 4″ in diameter and 57″ in length. These expansion joints are designed for an operating temperature or 500°F at 30 psig, with a spring rate of 189 lb./in. and can absorb 8″ of axial compression. The units were 100% dye-penetrant and air soap & bubble tested prior to shipment.
4″ Diameter / Single: 50″ and double: 87″ Face-to-Face
Design:
Inconel 625 Bellows / Carbon Steel
Material:
400°F / 400 psig
Testing:
Hydro-tested at 600 psig
These single externally pressurized expansion joints were custom designed by U.S. Bellows for a hot water piping system at an Air Force facility in California. All units are 4″ in diameter, with the single units having a length of 50″ face-to-face and double units having a length of 87″ face-to-face. The expansion joint’s bellows were fabricated from Inconel 625 and all other components from carbon steel. They are designed for a temperature of 400°F at 400 psig with 4″ and 8″ of axial compression. All units were hydro-tested at 600 psig prior to shipment.
4″ Diameter / Single: 50″ and double: 87″ Face-to-Face
Design:
Inconel 625 Bellows / Carbon Steel
Material:
400°F / 400 psig
Testing:
Hydro-tested at 600 psig
These single externally pressurized expansion joints were custom designed by U.S. Bellows for a hot water piping system at an Air Force facility in California. All units are 4″ in diameter, with the single units having a length of 50″ face-to-face and double units having a length of 87″ face-to-face. The expansion joint’s bellows were fabricated from Inconel 625 and all other components from carbon steel. They are designed for a temperature of 400°F at 400 psig with 4″ and 8″ of axial compression. All units were hydro-tested at 600 psig prior to shipment.
We can allow for a total of 16″ of axial compression with a double x-flex expansion joint with an intermediate anchor base that will allow 8 inches of axial compression on either side of the anchor base.
We can allow for a total of 16″ of axial compression with a double x-flex expansion joint with an intermediate anchor base that will allow 8 inches of axial compression on either side of the anchor base.
Understanding Material Selection: Metallic, Fabric, and Rubber
Understanding the various types of expansion joints is the first step toward selecting the right solution for your system. The primary categories are metallic, fabric, and rubber, each offering unique benefits and being suited for different operating conditions. These components ensure the lifespan of your infrastructure.
Metallic expansion joints, also known as bellows, are flexible elements used in piping systems to absorb movement caused by thermal expansion, vibration, and pressure fluctuations.
These are often made from thin-walled metal cylinders, such as stainless steel, that are formed into a series of convolutions or bellows. The shape of the bellows allows them to flex and compress, accommodating axial, lateral, and angular movement.
Single Expansion Joints– Designed to absorb axial movement and vibration in a straight run of pipe.
Hinged Expansion Joints– Accommodate angular rotation in a single plane, using a hinge to prevent axial and lateral movement.
Gimbal Expansion Joints– Allow for angular rotation in any plane, making them perfect for complex directional changes.
Universal Expansion Joints– Designed with two bellows joined by a center pipe to handle large amounts of lateral movement.
Elbow Pressure Balanced Expansion Joints– Deployed at a directional change in a pipeline to absorb movement while eliminating pressure thrust, eliminating the need for main anchors.
Toroidal Expansion Joints– Designed with smooth, omega-shaped bellows that offer high durability and high pressure capacity. Typically used in heat exchangers.
Thick Wall Expansion Joints– Engineered with extra-thick bellows to withstand high temperature and pressure applications.
Slip-type Expansion Joints– Designed with a sliding piston or sleeve design to absorb large amounts of axial movement.
Fabric pipe expansion joints are often used in ducts that carry hot gases at low pressures. The primary design parameters are the temperatures and flow rates of the gases, as well as the amount and abrasiveness of solids suspended in the gases. Layers of different fabrics can be combined to accommodate the varying temperatures and pressures within the system. The fabric belt may need to be replaced periodically.
Rubber pipe expansion joints are often used to compensate for minor misalignment and offset. The design is chemical and abrasion resistant and accommodates higher pressures than the standard metal expansion joints and eliminates sediment buildup. They feature an integrally flanged design, eliminating the need for gaskets, and are designed to absorb noise, vibration, and shock. This single, wide arch, spool-type rubber expansion joint is provided with hot-dipped galvanized retaining rings.
Understanding Material Selection: Metallic, Fabric, and Rubber
Understanding the various types of expansion joints is the first step toward selecting the right solution for your system. The primary categories are metallic, fabric, and rubber, each offering unique benefits and being suited for different operating conditions. These components ensure the lifespan of your infrastructure.
Metallic expansion joints, also known as bellows, are flexible elements used in piping systems to absorb movement caused by thermal expansion, vibration, and pressure fluctuations.
These are often made from thin-walled metal cylinders, such as stainless steel, that are formed into a series of convolutions or bellows. The shape of the bellows allows them to flex and compress, accommodating axial, lateral, and angular movement.
Single Expansion Joints– Designed to absorb axial movement and vibration in a straight run of pipe.
Hinged Expansion Joints– Accommodate angular rotation in a single plane, using a hinge to prevent axial and lateral movement.
Gimbal Expansion Joints– Allow for angular rotation in any plane, making them perfect for complex directional changes.
Universal Expansion Joints– Designed with two bellows joined by a center pipe to handle large amounts of lateral movement.
Elbow Pressure Balanced Expansion Joints– Deployed at a directional change in a pipeline to absorb movement while eliminating pressure thrust, eliminating the need for main anchors.
Toroidal Expansion Joints– Designed with smooth, omega-shaped bellows that offer high durability and high pressure capacity. Typically used in heat exchangers.
Thick Wall Expansion Joints– Engineered with extra-thick bellows to withstand high temperature and pressure applications.
Slip-type Expansion Joints– Designed with a sliding piston or sleeve design to absorb large amounts of axial movement.
Fabric pipe expansion joints are often used in ducts that carry hot gases at low pressures. The primary design parameters are the temperatures and flow rates of the gases, as well as the amount and abrasiveness of solids suspended in the gases. Layers of different fabrics can be combined to accommodate the varying temperatures and pressures within the system. The fabric belt may need to be replaced periodically.
Rubber pipe expansion joints are often used to compensate for minor misalignment and offset. The design is chemical and abrasion resistant and accommodates higher pressures than the standard metal expansion joints and eliminates sediment buildup. They feature an integrally flanged design, eliminating the need for gaskets, and are designed to absorb noise, vibration, and shock. This single, wide arch, spool-type rubber expansion joint is provided with hot-dipped galvanized retaining rings.
Externally pressurized pipe expansion joints, also known as X-Flex expansion joints, are suited for piping systems that require large amounts of axial compression or extension. In externally pressurized pipe expansion joints, the bellows elements are arranged so that the media flow is on the external surface of the bellows. Externally pressurizing the bellows eliminates pressure instability as a limitation to the design and permits the absorption of large amounts of axial expansion. Our QC department conducted various NDT examinations (X-Rays, PMI, Penetrant Tests, and Hydro Tests). Also provided were “weld maps” and MTR’s for client review and inspection. At U.S. Bellows, we are constantly developing and assisting client engineers in this effort toward decarbonation by designing innovative products to accommodate new and unusual design specifications.
