PT&P manufactured 266 variable spring supports for a refinery in Texas. The variable spring hangers include chained travel stops for ease of disengagement and reinsertion during plant shutdowns. Variable springs (a type of Compression spring) are used in a wide range of applications (including various Low Carbon Capital projects, CO2 removal units, and Infrastructure improvements) to support the piping system. The variables are fabricated from carbon steel and hot-dipped galvanized to protect against corrosion. The PTP-2 variables were designed for loads up to 13,850 lb. and movements up to 0.1875” upwards. The PTP-4 variables were designed for a maximum load of 15,050 lb. and movements up to 0.8125” upwards. Each spring hanger underwent standard load testing and QC tests. PT&P also provided constant supports for loads that remain uniform throughout the deflection cycle and sway struts for controlling vibration and shock loading while restraining movement due to thermal expansion for this order.
PT&P received a rush order this past week for variable spring supports at 4:41 pm, quite late into the workday; however, this is business as usual, our manufacturing facility in Houston, TX operates 24/7 to support our customers.
In this case, the customer facility, an olefins plant was incurring a significant loss and needed to replace the springs to resume operations as quickly as possible. The seven (7) variable springs were designed, fabricated, and shipped within 2 days. The F-type variable spring support is designed to support piping from below, directly from the foundation, concrete column, or supporting structural pipe rack steel. Adjustment is made by inserting a bar into holes in the load column and turning the load column as a jackscrew. The base plate is bolted to the case and has four holes for fastening.
As global leaders in variable spring manufacturing, we used our adaptive manufacturing processes in which the PT&P pre-fabricated component parts that make up these variables are easily assembled when orders are placed. These variables were fabricated from carbon steel and hot-dipped galvanized for corrosion protection. They are designed to support loads ranging from 713 lb. to 1668 lb. and movements of 0.148” to 0.133”. Load and travel tests, along with Q.C. inspections were performed before shipment. Variable springs are used in mills, refineries, chemical, plastics, polymer, solar, power, biochar, renewables, carbon black, LNG boilers, food, packaging, and wastewater treatment plants to support piping as it goes through its’ range of movement.
Fronek Anchor/Darling, a division of PT&P, designed and manufactured hydraulic snubbers for Geothermal power plants. Historically, these plants are located near tectonic plate boundaries in the Earth’s crust where thermal activity is easily tapped into. This heat energy is transferred into electrical energy through the use of turbines, generators, and heat exchangers. These snubbers are fabricated from stainless steel and include a special paint system suitable for a Hydrogen Sulfide (H2S) environment. All the snubbers for this application were a 2-1/2 bore size, capable of operating at loads up to 10,000 lb., and were provided with either 6″ or 12″ of available stroke. The Pin-to-Pin dimensions ranged from approximately 36″ to 54″ Each snubber was tested at its rated capacity to assure acceptable dynamic performance once it is installed in the field.
PT&P manufactured cryogenic pipe saddles for LNG transportation pipelines. These types of insulated supports have been utilized in LNG plants around the world. Insulated supports are also used on cold piping in semiconductor plants or plants that make batteries to eliminate condensation. This particular type of insulated pipe saddle assembly was fabricated with a carbon steel base plate, 304L stainless steel saddle, and an insulation block. The overall size ranges from 25” x 19” x 12-¾” to 29” x 25” x 13-3/8” and designed to isolate the pipe temperature from below the structure. These pipe shoes were manufactured to support pipe sizes ranging in diameter from 36″ to 42″ NPS.
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 the 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, which 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.
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.
Pre-Insulated pipe supports were designed for high-temperature service at an oil refinery for a client that specializes in the engineering and design of fired heaters, furnaces, pre-heaters, and heat recovery systems. These high-temperature pipe supports were fabricated from carbon steel and designed for pipe sizes ranging in 36” – 42” diameter and are not only used for new construction but also upgrades and revamps. The “hot shoes” were designed with the addition of “Spring Washers” (not shown here) to maintain consistent clamping force when the pipe expands and contracts. The insulation is 3″ thick and comprised of High-density Calcium Silicate (asbestos-free) structural inserts treated with water repellant. Standard quality tests were performed before shipment. Our hot shoes are used extensively in Refineries, Styrene Plants, Hydrogen Plants, LNG Facilities, Semiconductor Fabrication Facilities, and General Building Construction.
These compact spring supports were custom-designed to support large diameter piping at a chemical plant that manufactures ethylene, propylene, butadiene, benzene, propylene oxide, styrene monomer, and other derivatives and gasoline-blending products. They are designed for large loads (13,623 lb. to 24,038 lb.) and a small confined space with limited thermal movement (from 0.2″ to 0.3″). Compact spring supports (or disc springs) minimize excessive loads on sensitive equipment, so these types of spring support the same load as a conventional variable spring but with a smaller “working range” and utilizing 25-50% less space. They are ideal for locating under equipment flanges or other locations where space is limited. The housing is fabricated from A-36 carbon steel and hot-dipped galvanized to protect against corrosion. They have an installed height of 13″ – 15″ and are 21″ in diameter. The “disc springs” are engineered using stainless steel. Each assembly underwent load testing and other NDE prior to shipment.
PT&P custom-designed constant spring support assemblies for heat recovery steam generator at a combined-cycle power plant. These power plants utilize gas turbines, steam turbines, heat exchangers along with other components to make use of “exhaust waste” for a more efficient system. These 200-F Type constants were fabricated from A36 carbon steel and include a hot-dipped galvanized finish. The spring coils are formed from alloy steel and are neoprene coated. They are designed for an operating load for up to 886 lb., and up to 6″ of maximum travel. They are placed beneath the unit being supported and allow for movement in the vertical direction (up or down). The dimensions are 13″ W x 31″ L x 18-1/2″ H. Standard load and travel tests along with a quality control inspection were conducted prior to shipment.