In the oil and gas industry, repair activities are critical to keep the maintenance costs of turbomachinery equipment down. Several repair technologies can be applied to various components of turbomachines. When dealing with gas turbines, the repair of turbine rotor blades has always been a very sensitive topic, given their critical application and their impact in terms of cost on the whole turbine lifecycle. Specifically, cracking and wearing of blade tips are some of the most common failure modes. Thus, the repair of these failure modes is of paramount importance, both for the original manufacturer as well as its aftermarket competitors. The present paper describes blade tip repair technologies from an original equipment manufacturer standpoint. Three different approaches are introduced and described for tip restoration. Laser cladding is presented first, since it is one of the most common technologies for this application, and then original equipment manufacturer which is currently being applied is presented. Then, cold metal transfer and direct metal laser melting technologies are investigated. A technologic and financial assessment is made to drive the technology selection for the turbine blades restoration.
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