World's Largest Milling Machine...
A grout challenge not for the meek.
to Latin America
Nestled in the rich, fertile, wine-growing foothills of the Argentine Andes Mountains and under the shadow of Mount Acongagua, the highest peak in the Western Hemisphere, lies Mendoza, Argentina, the site of the installation of the largest milling machine in the world. Supplied by Ingersoll Milling of Rockford, Illinois, for their client, IMPSA, this machine would allow the owner to fabricate large components for hydroelectric dams around the world.
The engineering, manufacturing, shipping and reassembling of a machine of this magnitude is quite an undertaking. The nearly 500-ton milling machine was to sit on a 10 x 10-meter, 20 cm (8") thick steel baseplate.
The plate, which was manufactured in Michigan, contained so many channels, compartments and slots, that it looked much like a giant waffle underneath. The finished plate was actually eight smaller plates bolted together into one unit at the site. Pre-meetings were of utmost importance...
|Shipment of L&M CRYSTEX arrives at Mendoza plant... Grout pump is in the foreground||Full view of massive mill table... Grout mixing station located at top of photo||CRYSTEX grout mixing station|
The base plate, along with the machine, was to ultimately rest on non-shrink structural grout. Specs called for a non-metallic, non-gaseous grout due to the wet environmental conditions. In order to insure 100% contact between the grout and plate, it was necessary to place the grout material in a fluid consistency because of the numerous, confining structural braces, key ways and channels. An equally important challenge was that the grout had to remain flowable (pumpable) for periods up to 60 minutes in temperatures nearing 100-degrees F...it was summer in Argentina. Even in the extremely fluid state, the grout had to provide outstanding repetitive dynamic load stability from compressive strengths of over 10,000 psi. All of these criteria were key in determining the right grout for the right job. The product selected was CRYSTEX grout by L&M.
Following meetings with L&M and the heavy machinery managers, project managers, service managers and work crew, the necessary preparations were made to ship the plate, equipment, material, tools, personnel, pumping equipment, hoses, nozzles, forms, etc. Additional challenges (besides the immense physical size of the project) also included variable grout thicknesses. Planning meetings were also held to determine the number of personnel required, and the role each person would play in this mammoth project. This project required actual grout height to range from less than one-inch, to nearly six inches. Multiple mixers and grout pumps had to be on site to insure a continuous mixing and grout flow in the event of a mechanical breakdown. Additional mixers were utilized as backup to provide a secondary source insuring the grout would be placed continually and rapidly.
|Pumping CRYSTEX fluid grout into small grout filling ports||End view of mill table... CRYSTEX was placed between the mill table and the structural base||Grout crew celebrates completion of "World's Largest Mill Table" CRYSTEX grout placement|
Personnel were assigned as follows: two people mixing, one operating the grout pump, one placing the grout, two people observing the height and the path of the grout to insure maximum bearing area. There were nearly 100 holes specially cored into the tops of the baseplate for pumping grout. Special nozzles had to be added to access the cored holes.
Estimating the grout material was very difficult, but not impossible. An overestimate of 25% was given to account for torn bags, material consumption from errors made in calculation due to the foundation depth variances and other, unforeseen circumstances. Temperature also played a major role in this project because of the 100 F + degree heat.
Water Source....Another challenge on the Mendoza project was finding a clean, potable water source with transfer hoses and shut-off valves. The owner was able to install a clean and reliable water source within ten meters of where we were going to mix the grout material.
Forms had to be sturdy, waterproof and constructed to allow a space of approximately one-inch around the edge of the baseplate. It was decided to place the forms tightly against the plate, dry packing around the base of the boards to eliminate leakage. Due to the size and configuration of the plate, numerous grout placement holes had been cored into the top of the plate...therefore, a flow box was unnecessary.
Following a highly involved "Plan-Your-Pour" placement meeting, we went to work....Due to the complex configuration and huge physical size of the underside of the plate, the decision was made to place the grout at a fluid consistency in an effort to flow it in and out of the many hidden compartments, key ways and lifting holes. The grout was poured in two, separate lifts...this decision was made to reduce the significant exothermic heat generated during the early stages of hydration due to the high percentage of cement found in today's high-strength grouts.
For the hot weather conditions of Mendoza, we used cool mixing water, stored the grout in a shaded, cool area and, in an effort to keep the baseplate cool, we took steps to decrease the amount of sunlight allowed into the facility.
Cleaning and 24-hour pre-soaking the concrete substrate with water was an essential step to be taken before placing the grout. Cleaning and roughening also had to be done to insure proper bond of the grout to the concrete substrate. Extra care had to be taken with low spots, where water tended to gravitate.
After the placement pattern had been determined, the L&M officials and installers were ready to begin grouting. We began by placing the grout from one side and moving the flowable grout in one general direction in an effort to push out any remaining water that had been left underneath the plate. We grouted for nearly 11 hours straight....placing nearly 35% more of the grout material than was originally planned. A wager of one admittance ticket to the upcoming Mendoza Wine Festival was made between the grout installer and the machine's future owner that there would be enough grout material to complete the job. After four, solid 11-hour days of grouting, the forms were removed and edges were sealed to trim-up any voids left by the forms in order to bring the job up to appearance standards.
During the placement, L&M advisors performed the necessary quality control sampling-taking 2-inch x 2-inch cube setups from a broad cross-section of the supplied material.
After seven, continuous hours of pumping on the fourth day...we had completed grouting the world's largest milling machine. In proper Argentine tradition, a celebration was held with singing, comradery and lots of photo-taking. The CRYSTEX "Dancing Grout" was the star of the day. The installers cheered each time the fluid CRYSTEX pushed through the "Core" holes and "danced" at the top of the huge plate.
CONCLUSION....Choose the best grout...To save money and trouble. L&M grouts are your best assurance of long-term grouting performance. L&M provides you with a combination of premium grouting material, consistent testing and skillful workmanship. We at L&M know that no one component can compensate for the lack of other key elements. However, L&M's quality grouts can be a labor-saver....even a job saver. This was proven in Argentina for the grouting of the "World's Largest Milling Machine". High strength, high flow, extended placement time, non-shrink at all flow levels, economical and experienced field technical help all add up to guaranteed confidence.
Whether it's the world's largest milling machine or simply that smaller, yet equally critical machine base at your plant, the L&M family of precision grouts are the right choice. Always consistent...always predictable....You can count on L&M grouts to perform ...GUARANTEED!
Roberto Rios, L&M
Latin America (left) and
Greg Schwietz, President
L&M Construction Chemicals (right)
© 2001 L&M Construction Chemicals, Inc. | ConcreteNews Spring 2001.