For a Precision Fit. The economy of the modular concept in the design and fabrication of Columbian Bolted Steel Tanks has been consistently proven. Factory automation and high-quality manufacturing procedures eliminates the field expense of welding crews, special expertise and costly tools. However, what is built-in at the factory is only as good as its field erection. Just as a factory baked-on coating is essential for effective corrosion resistance, factory craftsmanship is essential to efficient field erection. For years, Columbian has enjoyed the "Master Crafted" reputation for our tank performance. Components that erect more smoothly become tanks that perform better in liquid storage. Factory application of coating plus optional encapsulated bolt heads and nuts make this entire area 100% corrosion resistant. The coating extends under gasketed seams; under field coating conditions, such total protection is impossible. Factory formed flanges at horizontal seams give the bolted tank added structural strength. Special gaskets and sealants create leakproof joints at both horizontal and vertical seams. Factory applied coating and encapsulated bolt-heads provide corrosion-resistance at all seams, joints and connections. Bottom segments are coated on both sides with Trico-Bond EP and assembled with galvanized nuts and bolts. Use of optional encapsulated nuts provides maximum corrosion- resistance against internally-stored liquids.   Click Here To visit the Columbian Tank Website