We’re in a new space age.
Advances in technology and a pioneer’s mindset together drive breathtaking space missions that will park rovers on asteroids and land humans on Mars.
None of that is possible without the essential ground support systems that handle the complex cocktail that is liquid rocket fuel.
Engineers from NASA had this in mind when they approached specialty contractors about building next-generation process piping skids for the Liquid Fueling Facility (LFF) at the agency’s Wallops Island launch site.
An unmanned resupply mission to the International Space Station (ISS) would depend on timely delivery of these crucial piping systems.
The need for a fueling station arose when NASA began subcontracting its supply deliveries to the ISS. After visiting our fabrication facility in Northern Virginia, it was clear to the LFF engineers that High Purity Systems was an ideal partner for fabrication and installation of the process piping skids, which were the first of their kind ever to be installed on the east coast.
You don’t just pour gasoline into a rocket. Fueling these vehicles requires some seriously complex equipment capable of handling super-cooled liquid gases.
In this case, the project called for fabrication and installation of 14 skids, each performing a critical function prior to launch:
We designed the skids with job-specific specialty components according to precise specifications for operation in severe weather and harsh operational conditions.
Some of the skids were as big as eight feet wide by 22 feet long and the frames were assembled with structural steel. Then, they were hot dip galvanized to ensure maximum corrosion resistance. To cut down on conductive electrolysis, we machined and installed micarta laminate sheets as standoffs between the steel supports and the stainless steel piping.
When you’re that close to the ocean, anything less than maximum corrosion protection would have been inadequate.
Each skid had at least one inlet and outlet. Some were equipped with more than one of each. From the inlet flange, the stainless steel pipe system meandered through a series of valves, regulators, flow meters and specialty equipment to meet the outlet flange. Planted over top of the main piping was a system of hangers for more tubing. The ¼” and ½” tubing was bent, flared, routed, and rose together before splitting off to go to its final connection point.
We used some of the tubing to pipe out pneumatic controllers on valves and other tubing to supply pressure to gauges and flow-indicators. Each skid was a cleanly designed, efficient stainless maze. Once we finished the piping, electricians mounted switch boxes and finally installed safety shut-offs and indicator lights.
The crews had to pay close attention to detail to adhere to welding codes. The typical process piping code — ASME B31.1 — was in play, as was ASME B31.3 severe cyclic criteria. Meeting B31.3 requirements was mission-critical due to the extreme temperature fluctuations the system would endure.
Stainless piping in fuel skids goes from ambient temperature to the -100s of degrees Fahrenheit in a matter of seconds as super-cooled liquefied gas transits through the lines.
We took extreme care to guarantee that each weld would perform reliably for the life of the system. The project utilized equipment including TIG welders, tube and pipe flaring equipment, and our mandrel pipe bender.
Mandrel pipe bending was an unsung hero on this project, as we explain below.
We knew from the start that we’d have to contend with two main challenges.
First, our customer’s ambitious project schedule meant we needed to find ways to streamline construction.
Second, heavy reliance on specialty stainless steel components added long lead times to the equation. Very few manufacturers make these components to begin with; none keeps a ready inventory.
To address these challenges, we chose to stage the materials for all 14 skids in our fabrication shop at once to build the systems concurrently. This allowed our crews to always gain ground on the job even if some specialty components had not been delivered. Staging in this way meant that delays resulting from longer component lead times never rippled outward.