The Air Preheater Company surpassed its own record for minimum installation costs with the introduction of the Modular™ and Semi-Modular™ rotors.  Installation time can be reduced by as much as 34% over conventional field-assembled designs. Heat transfer surfaces are preinstalled in full-sector modules that are prefabricated at the manufacturing plant with all structural welds completed under controlled conditions. Shipping cost savings are realized because the modules serve as carriers for the individual heat transfer surface containers.  In addition, handling costs and assembly time at the installation site are substantially reduced. Full-sector modules are simply pinned (not welded) to the rotor post to reduce field welding requirements.  This method of attaching the sectors throughout the rotor assembly results in a discontinuous stress-free structure that significantly reduces thermal distortion and its associated leakage. Semi-Modular™ Air Preheater during construction › Locate a Salesperson