A total of three rectangular fabric expansion joints and six round fabric expansion joints were custom designed for an offshore oil extraction and natural gas project. The rectangular joints are 56″ x 81″ I.D. x 25″ O.A.L. and the round joints are 105″ dia. x 24″ O.A.L. 309 stainless steel was used for the duct, 310 for the liners, 316 for the covers, 321 for the studs, 309 for the flanges. The fabric belt was a three layer belt with an inner layer of glass cloth, a layer of KO wool and an outside layer of reinforced PTFE. The expansion joints were designed for 1 psig at a temperature of 1100°F. The rectangular joints were designed for 2″ axial compression, a 1″ extension, and a 1″ lateral offset. The round joints were designed for 4″ axial compression, a 1″ extension, and a 0.5″ lateral offset. All welds were dye penetrant examined.
B31.1 Operations and Maintenance
According to ASME B31.1 Chapter VII Par. 140 a program shall be established for the assessment and documentation of the condition of all CPS (Covered Piping Systems) in power plants.
CPS Systems are defined in Chapter 1 Par 100.2, as systems on which condition assessments are to be conducted. This includes the following systems as a minimum.
NPS 4 and larger main steam, hot reheat steam, cold reheat steam, and boiler feedwater piping.
NPS 4 and larger systems that operate above 750°E (400°C or above 1,025 psi (7,100 kPa)
Other systems may be included as CPS by an Operating Company, based on their judgment. Appendix V of the code is titled ‘Recommended Practice for Operation, Maintenance, and Modification of Power Piping Systems’. This addendum is non-mandatory; however many Power Industry operating companies’ insurance carriers are now invoking Appendix V with increasing frequency, and this is affecting conditions of their agreements with the operating companies.
Piping Technology and Products Inc. (PT&P) has for some time been performing surveys and assessments in accordance with part H of Par. 140, that requires hot and cold walk-down readings and assessment of pipe supports, operated within the creep regime of the pipe. These assessments are helpful in identifying, sagging lines, deformation of supports, and damage caused by upset conditions, and/or incidents, attributable to operational malfunctions, dynamic/thermal or hydraulic events.
PT&P has been performing this service for many power generation companies. Preparation of documentation, retrieval and compilation of files for a CPS assessment, has just been completed for a major U.S power generation company. Ten large power plants were involved, and the original predominantly high-energy pipe support drawings, all engineered and designed by PT&P, were retrieved from PT&P archives dating back ten years.
Please feel free to contact us at firstname.lastname@example.org and we will be happy to answer any of your technical questions about our survey capabilities, as well as any other engineering or field services that your organization may need.
U.S. Bellows 101: Expansion Joint Basics Webinar
This Webinar is over… to view the recording, go to http://www.usbellows.com/news/webinar_index.html
* Live Webinars are approved for 1 PDH credit for TX P.E.’s
This presentation will briefly touch on the basics of fabric expansion joints; however, is mainly focused on the various designs, material details, and applications. Learn how fabric expansion joints are engineered and fabricated for various applications and the many factors that influence those designs. View the abundance of materials used, including Fluoroplastic and Fluoroelastomer, and their respective capabilities. Take a journey through a Fossil Fired Power Plant and see exactly where fabric expansion joints are required.
U.S. Bellows, Inc., a division of PT&P, has more than 50 years of experience designing and manufacturing expansion joints, along with replacement and repair services.
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.