bolted tanks tank manufacturing fire protection tanks BOLTED TANKS Columbian TecTank™ company manufacturers bolted tanks and shop-welded tanks in coated carbon steel, aluminum and stainless steel. For bolted storage tanks there is an option of galvanized steel. Columbian TecTank™ API bolted tanks are used extensively in oil field applications. Columbian TecTank™ bolted tanks are suitable for a variety of industrial liquids. Bolted tanks may be fitted with plastic encapsulated bolt heads and nut caps for additional protection. The economy of bolted tank fabrication, reliable assembly and proven quality are ideal for industrial liquid storage applications.