The Specialized Carriers & Rigging Association (SC&RA) has announced the winners of the Rigging Job of the Year Awards. The awards went to Barnhart Crane and Rigging, Memphis, Tenn., in the Jobs over $750,000 category; Atlas Industrial Contractors, Columbus, Ohio, in the Jobs between $150,000 and $750,000 category; and George Young Companies, Swedesboro, N.J., in the Jobs under $150,000 category.
Over $750,000: Barnhart Removed and Replaced Large Components at Wisconsin Nuclear Plant
Barnhart Crane and Rigging was contacted about a nuclear plant upgrade project at the Point Beach Nuclear Station (PBNS) in Two Rivers, Wis., that called for removing and replacing four feedwater heaters, a condensate cooler and two main feed pump/motor skids inside the condenser shells of both units of the power station. However, in many places, the flooring of the facility would not support the weight of the feedwater heater. Plus, height restrictions added major challenges.
The general contractor for the plant upgrade was Bechtel Power, with Barnhart working as a subcontractor to Bechtel. The upgrade would result in two power units receiving a 17 percent increase, equal to 260 additional megawatts thermal (MWt).
Barnhart’s scope of work was to provide design fabrication and field engineering, project management, field supervision, operators, equipment and rigging for the removal and replacement of the components in two units. The most challenging task for Barnhart was to remove and replace four feedwater heater vessels weighing up to 124 kips through a very challenging travel path. The feedwater heater vessels measured 42 ft. long by about 6 ft. (12.9 by 1.8 m) in diameter and weighed approximately 124,000 lbs. (56,245 kg).
Barnhart’s plan for the project was to cut doors into the side of the building in order to pass the feedwater heaters in and out using the company’s signature Tri-Block rigging system. In the building, there were numerous obstacles and elevation limitations, plus the floor limitations. Lightweight grating and floor beams would not support the feedwater heaters’ 100 pounds per square foot. The feedwater heaters had to slide through the facility on a tedious obstacle course that involved raising, lowering and rotating.
Critical to the removal and replacement of the feedwater heaters was Barnhart’s design of a host of new tools. All of the tools developed for the job were tested and retested at Barnhart’s Memphis facility. Among these tools was a sliding gantry and track system used inside the plant. The system required four jacks per gantry for a total of eight jacks in each bay, double acting jacks, a light slide system to run each gantry leg, slide shoes on top of each header beam and 28 LP/HP hose connections and two multi-purpose pumps.
Barnhart also designed a crossing gantry track system to allow the heaters to move through the plant safely. Additional innovation involved the creation of a sliding swiveling rigging device (SSRD), which allowed the long, narrow heaters to be rotated when fully suspended by the SSRD and two legs of gantry.
Barnhart also designed a gantry saddle system for holding the new heaters in place during lifting and installation. Rigging innovations included the use of air skates, jacking and traditional sliding, sliding gantry and sliding heater links.
To move the feedwater heaters in and out of the building doors a 500-ton (453 t) capacity all-terrain crane was used on the outside of the building. The heaters were transported into and out of the facility on Barnhart’s Goldhofer self-propelled modular transporter (SPMT) systems.
The engineering of the project required 5,000-plus man hours, including methodology, concept design, interference identification, integrated planning with Bechtel and the owners, fabrication design, new equipment mockup and testing and field-based risk management. For the project more than 200 engineering drawings were submitted.
The key distinction on this job was the overall limitations imposed including contractual limitations; time/schedule limitations including a crunched planning schedule and critical path activity; physical limitations including ground, floor, ceiling and condenser structure bearing limitations, travel path limitations, quarter inch clearances of immovable plant, and single pick point required on Unit 1 heaters; and weather limitations including rain, cold and blizzard conditions and consistent wind gusting.
Working in a nuclear environment requires above and beyond safety measures. For the job Barnhart provided an overall job risk assessment, provided new tools that would assure safer operators, employed full time safety champion on each shift, performed two-minute drills, instituted continuous improvement cards and participated in a plant observation and rapid trends program.
The job involved 22,300 Barnhart man hours plus 30,000 more Bechtel craftsmen hours under Barnhart’s supervision, no first aids, no accidents or recordables and no lost time accidents.
$150,000-$750,000:
Atlas Industrial Assists in Rebuilding of Damaged
835-Megawatt Generator
In January 2011, at the peak of the winter lighting and heating season in Ohio, a generator at FirstEnergy Corporation’s Sammis Station threw its rotor. National Electric Coil (NEC) was dispatched to perform the emergency repairs. NEC in turn called Atlas Industrial Contractors to assist in the tedious job of rebuilding the damaged generator.
The main obstacle in the repair process was the 835-megawatt generator’s location astraddle two building bays with structural steel obstructions directly overhead. NEC’s method for repairing the generator was to upend the stator housing. But due to the overhead obstructions, the stator housing would have to be relocated before upending could occur.
As NEC and Atlas prepared their safety, lifting and repair plan, FirstEnergy was anxious about potential damage to the stator housing and turbine pedestal. Generator OEM Siemens also was concerned that the end bell might deform during the lift or while resting on the foundation during the core installation, irreparably damaging the generator.
Atlas turned to Ruby and Associates of Farmington Hills, Mich., to perform a finite element analysis of the stator housing and the lift plans. It was determined that reinforcing plates should be temporarily installed on the stator housing during the rebuild. In addition, support stands were designed to distribute some of the weight of the stator to the lower lift trunnions.
By mid-February all specialized components had been fabricated, a 1,000-ton (907 t) gantry system procured from Rigging Gear Sales installed and the stator ready to be relocated and rotated. In preparation, the rotor was removed from the stator housing, decoupling the generator from the turbine. NEC also removed the existing core, which was comprised of some 750,000 individual laminate plates that weighed 400,000 lbs. (181,437 kg). Given the reduced weight of the empty stator, this was the easier part of the move. Fully assembled, the generator weighed 400 tons (363 t), and the plan and the engineering had to account for this.
Atlas employed a Lift Systems 34PT10060WTIC 1,000-ton (907 t) gantry system with a height elevation of 40 ft. (12 m). Atlas also used two legs of its 34PT5400WT 500-ton (453 t) gantry connected to Atlas’ tailing fixture to act as the tailing gantry during the lift process. Eighty feet (24 m) of 30-inch track and 30 ft. (9 m) of 15-and-a-half-inch (39 cm) track were deployed to support and direct the rolling gantries.
With the gantries and tracks in position, the reinforcing plates on the side of the stator were installed and four lifting trunnions were mounted on the stator housing. Engineers determined that high friction forces would have to be overcome during the uprighting or there was a chance that the stator and lift system would lurch unpredictably during rotation. In response, an ultra-low friction bearing was incorporated into the lift links. The lift links, lift trunnions and other specialty components were fabricated by Atlas Steel. The lift links fit snugly over the upper trunnions and assured a smooth up righting process and kept the assembly in a plumb condition.
For the stands to share load with the end bell of the stator as it increased in weight due to reinstallation of the laminate plates, shims were installed under the stands at a critical point in the restacking process. Shims also were employed under the steel grillage supporting the stator end bell to provide uniform contact of the stator bell against the steel.
The Atlas team submitted pre-task planning and job hazard analysis to both NEC and FirstEnergy. All project personnel attended FirstEnergy’s site-specific safety orientations. Atlas conducted its own full-scale safety orientation, including comprehensive schooling all team members and conducting walk-throughs of all phases of the project. A series of test lifts also were performed.
With the tailing fixture in place, the generator was moved away from the turbine in a series of coordinated vertical lifts and horizontal gantry movements to keep the stator and attached piping clear of the turbine and generator foundations and to maintain clearance with overhead obstructions. As the tip-up operation began by raising the 1,000-ton gantry system at the turbine end of the stator, the 500-ton system was used to synchronize with the movement of the 1,000-ton system during rotation of the stator. Pre-planned hold points were built into the lifting schedule to ensure all axis’ of the stator and gantry systems were within allowable tolerances.
Once vertical, the stator housing was moved to the far west end of the gantry tracks. At this point, support steel grillage beams were positioned and the lower trunnion support stands moved into place.
Atlas crews left while the rotor was repaired and NEC began restacking the core, which took about three months. During restacking, Atlas crews returned once to install shims beneath the support stands to support the additional weight added during restacking. With the rotor and laminate plates reinstalled, the stator weight was back to its original 400 tons.
After the restacking of the laminates was complete, it was time to return the unit to horizontal and remarry it to the turbine and exciter. Gantry lifting pressures and the tractive effort to overcome rolling resistance would be markedly different this time since the stator was twice as heavy. With the stator clear of the support stands, the generator was repositioned through a series of coordinated vertical lifts and horizontal gantry movements.
Under $150,000:
George Young Relocates Historic
103,000 Pound Monument
When Drexel University recently started an expansion project that involved the construction of a new 12-story College of Law, the first challenge was to relocate a 107-year old, 103,000-lb. (46,720 kg) bronze statue of founder Anthony J. Drexel, which sat where the new building would be constructed. A call was made to George Young Companies, an expert in handling fine art and historic monuments, to perform the project.
The effects of time and pollution had taken their toll on the monument’s Italian granite base. Fissures, cracks and broken lettering marred the valuable work of fine art. The monument’s site was ringed with underground subways and above-ground buildings, making the use of a large crane expensive and heightening risk.
Goals were set for the project including implementation of Young Group’s Beyond Zero Safety Program as the project’s Number One goal. Protection of the monument’s stone base and eliminating stone loss was considered vital. Soil and ground strength were reviewed and additional loads of crushed stone were installed to provide a stable lifting and skidding surface.
Young’s Heavy Rigging Group reviewed the site and suggested applying its heavy rigging systems to relocate this rather light piece. The decision was made to relocate the monument monolithically as opposed to suffering the stone loss that dismantling and subsequent re-assembly would likely pose.
Prior to handling and rigging the monument for the move, the granite base’s multiple fissures were injected with epoxy to stabilize the stone. Areas where engraved lettering was unstable were fortified with Japanese Tissue, a long-fiber vegetable material. Corners were edged in protective devices to prevent damage from incidental contact. Finally, Ethafoam was placed between the rigging equipment and the monument base to absorb vibrations that might cause fissure to spread.
Due to the presence of subways directly underneath the site, the rigging, lifting and relocation plan called for eliminating the use of heavy cranes. Young’s Heavy Rigging Group opted to utilize in-house rigging systems that could lift the valuable and delicate monument, valued at up to $5 million, without a problem or issue.
Interestingly, the university was able to supply notes to the Young Group from when the monument had previously been moved in 1966 and again in the mid 1990s by George Young Companies. The discovery of notes from the previous move in 1966 were instrumental in the rigging plan.
They were the handwritten notes of George Young’s father, and they explained how he designed the foundation, including a pair of 10-in. square beam pockets underneath the marble base. Since the foundation was covered, the notes presented the only information indicating those pockets existed.
After excavation of the area surrounding the monument, a pair of beams were threaded into foundation pockets below the monument’s granite base. The lower lift beams threaded into the foundation pockets were attached to lift beams supported by one of Young’s 100-ton capacity J&R Engineering hydraulic gantries. The gantry lifted the monument to its new elevation so that a Young Group 400-ton capacity turntable could be placed under the monument’s base and on top of crane mats that had been inserted.
The monument was rotated on the turntable exactly 14.5 degrees to match the new foundation orientation located 60 ft. (18 m) away. After reconfiguration to a four-lift beam arrangement, the hydraulic gantries lifted the monument a second time and Young’s 500-ton Hydra-Slide system was installed under the base.
Multiple 8 ft. (2.4 m) long custom built skid-shoes allowed for numerous safety cribs to support the lower lift/skid beams and the granite base and easily slid the 103,000 lb. monument into final position over the waiting foundation. The J&R Engineering hydraulic gantry performed flawlessly as it lifted the monument for the third and final time, lowering the monument into position after the removal of the Hydra-Slide rail system.
Upon inspection, all of the engineering and precautions taken resulted in a zero stone loss result and a satisfied client. Over the years, the company has handled almost 150 different large works of fine art, many of them multiple times.
The Specialized Carriers and Rigging Association (SC&RA) is an international trade association of more than 1,300 members from 46 nations. Members are involved in specialized transportation, machinery moving and erecting, industrial maintenance, millwrighting and crane and rigging operations, manufacturing and rental. SC&RA helps members run more efficient and safer businesses by monitoring and affecting pending legislation and regulatory policies at the state and national levels; researching and reporting on safety concerns and best business practices; and providing five yearly forums where these and other relevant member issues can be advanced.
For more information, visit www.scranet.org.
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