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Boatbuilding: Portsmouth Naval Shipyard Streamlines Operations With Flexible Buildings

Maritime Activity Reports, Inc.

April 2, 2003

Portsmouth Naval Shipyard (PNS), harbored on an island between Kittery, Maine and Portsmouth, New Hampshire, has weathered many a storm since its creation in 1800 under President John Adams. As the nation's first naval shipyard, PNS has risen and fallen with the fortunes of sail, steam, and atomic-powered seacraft. In recent decades, it has reinvented itself as a top-notch provider in the life cycle maintenance of modern Navy submarines. Yet like other shipyards nationwide, PNS has been under pressure to streamline operations and maximize productivity. To this end, the shipyard has been upgrading its facilities. As buildings for storage, workspace, and equipment protection are torn down or refurbished, there's been a critical need for weathertight, insulated temporary structures to fill the gap.

Previously, PNS staff built their own temporary structures by welding together I-beams, angle bar, tube steel, and plate. The structures were heavy, as well as difficult to move and insulate but sufficed until staff cuts and the decision to focus on core competencies made this method impractical.

Traditionally made structures are cumbersome and time-consuming as well, since they require builders to erect a frame, drape insulation, stitch-screw sheeting, then frame doors, windows, and ventilation. Erecting a 30 x 39 ft. building using conventional construction methods, for example, could take 12 weeks or more.

Moreover, the number of pieces involved - including girts, purlins, girders, trusses, insulation, as well as inside and outside sheeting with countless fasteners - combined with the inability to align sheeting holes on reuse, made relocation impractical.

Beyond this, a conventionally made structure could take months to get approval from the design and review process if even simple changes were made. However, due to emergent needs and fiscal realities, PNS often found itself needing a quick and economic solution for having a facility ready for use in 30 to 60 days. This short timeframe ruled out a conventionally erected facility.

The Nuclear Engineering and Planning Department, cognizant of PNS's production facilities, explored alternate methods of construction using pre-engineered metal buildings and the GSA federal supply service catalog. A competitive bid process resulted in the selection Kelly Industries of Fremont, Nebraska as the supplier. The Kelly Klosure buildings are designed to code, so the approval process was streamlined from weeks to days. Since structure, sheeting, and optional insulation are pre-installed in modular panels along with doors, windows, and ventilation at the manufacturer's facility, the buildings can be assembled "out of the box" eight to ten times faster than conventional facility erection.

Whereas conventional buildings need pre-set anchor bolts that align precisely with matching columns, Kelly Klosure buildings can be erected on existing concrete slabs, sonotube piers, or many other surfaces. For slab installation, erect the building piece by piece in the desired location, and then drill into the foundation below through existing holes in the panels. No pre-alignment is necessary.

Since sheeting and insulation are already attached to the panels, contractors usually need just wrenches and hand tools to bolt the panels together, drills to install foundation anchor bolts where needed, along with ladders for small buildings and a crane for large buildings. The panels are easily carried and assembled by individuals, like an erector set.

One PNS contractor was able to erect an entire 24 x 29.5 ft. building and a custom-made prefabricated metal floor in less than four days, with the manufacturer's onsite assistance. A 30 x 39 ft. building took just a single week to erect using the modular panel system, a very significant savings in time, contractor cost, and disruption of other activities, when compared to conventional construction methods.

Because the panels are interchangeable, the pre-framed doors and windows built into them can be moved, if necessary. For example, a door or window can be moved to a different part of the building, if located in an inconvenient position. Similarly, the structures can be quickly reconfigured by adding panels, or taken down completely, moved to another location, and reconstructed. The wall and roof panels may be unbolted, removed, or reconfigured to change length, width, and height dimensions at any time - for facility flexibility to accommodate a range of overhaul or storage needs. Since the system is panelized, if a building is relocated the sheeting and insulation are not removed; therefore, no additional holes are required for reassembly.

The Fremont, Nebraska manufacturer also proved responsive to PNS's special needs. On a recent project, the building had to straddle a railroad track to allow flat car access inside. A standard slab foundation was problematic as excavation was impossible, yet the building needed an adequate base to handle wind loads. The manufacturer quickly resolved the problem by supplying a metal base plate with "duck bill anchors" driven into the ground that eliminated the need for excavation. On another occasion, the company made modifications to its detachable roof that allowed two-12 ft. hatch-type doors to be installed. This enabled equipment to be lowered directly through the hatch doors, minimizing the need for crane lifts and boosting productivity.

Furthermore, because the pre-engineered buildings distribute load uniformly along the walls, no load concentration occurs, so no column support is needed. Without column interference, 100 percent of interior space is available for storage or oversized equipment. The pre-engineered buildings are designed to last for at least 30 years, and the panel frames themselves offer sturdy, interior attachment holes for lights, piping, or mechanical-electrical installations.

Portsmouth Naval Shipyard intends to continue using the pre-engineered, panelized buildings, reconfiguring and relocating them as needed, and transporting them in their accompanying storage racks. To date, the pre-engineered buildings have helped streamline PNS production efforts by providing secure enclosures that allow a rapid response to changing requirements. This has increased PNS' competitiveness and efficiency. The pre-engineered buildings also offer relocatability, design flexibility, and significant cost savings that boost the value of PNS's service to the Navy. As PNS continues to reinvent and streamline itself 200-plus years after its creation, it and other shipyards nationwide may increasingly look to pre-engineered, relocatable buildings as a means to more effectively carry out their maintenance and support missions.

Kelly Industries, Inc., a leader in pre-engineered permanent and relocatable structures for over 30 years, is a General Services Administration (GSA) authorized Federal Supply Service (FSS) contractor. Both active military and reserve units across the nation have used Kelly structures for a variety of uses: from storage, fabrication shops, showers, and latrines to offices, classrooms, and "live fire" observation towers. Weathertight, insulated or uninsulated Kelly structures are also widely used by other government agencies, including US Customs, Border Patrol, and the FAA (Federal Aviation Agency).

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