Rotary kinetic fluid motors or pumps – Working fluid passage or distributing means associated with... – Specific casing or vane material
Reexamination Certificate
1999-10-04
2002-03-12
Look, Edward K. (Department: 3745)
Rotary kinetic fluid motors or pumps
Working fluid passage or distributing means associated with...
Specific casing or vane material
C416S24100B, C219S121460, C219S1370WM, C219S145100
Reexamination Certificate
active
06354799
ABSTRACT:
BACKGROUND OF THE INVENTION
The present invention is drawn to the field of turbine engine components. More particularly, the present invention is drawn to a superalloy weld composition and a repaired component utilizing a superalloy weld composition.
The efficiency of gas turbine engines is dependent in part on the amount or degree of leakage of combustion gasses between the turbine blades or buckets and the shroud of the turbine section of the engine. To minimize the gap, the tips are generally subjected to a precise machining operation. However, due to machining tolerances, thermal expansion differences between the components, and dynamic effects, typically some degree of rubbing between the tips and the shroud occurs.
Due to the rubbing contact, such as after extended service in the field, the base material of the blade is exposed, generally leading to corrosion and/or oxidation of the blade. Extended corrosion or oxidation leads to an increase in leakage between the blade and the shroud and consequent performance and efficiency losses. It has become commonplace to repair worn components as a cost-effective option to replacement, in view of the relative cost of turbine components such as blades or buckets. In a known repair technique, a weld wire formed of a weldable superalloy composition is used in a ‘build-up’ process to restore the blade to its original or near-original geometric configuration. For example, a nickel-base superalloy weld wire can be used in a tungsten arc welding process by making multiple passes over the tip region of a nickel-base superalloy blade. Following welding, the tip region is machined.
While there are numerous commercially available weld repair alloys, there continues to be a demand for further improved weld alloys, particularly, nickel-base weld alloys for nickel-base superalloy components. In this regard, the present inventors have recognized a need for a nickel-base superalloy that has superior ductility to enable welding at room temperature (i.e., without preheating the component under repair), good oxidation resistance, and requisite high-temperature tensile strength and creep resistance.
BRIEF SUMMARY OF THE INVENTION
One embodiment of the present invention calls for a solid-solution strengthened superalloy weld composition, including:
about 10 to about 15 wt % Co;
about 18 to about 22 wt % Cr;
about 0.5 to about 1.3 wt % Al;
about 3.5 to about 4.5 wt % Ta;
about 1 to about 2 wt % Mo;
about 13.5 to about 17.0 wt % W;
up to about 0.08 wt % C;
up to about 0.06 wt % Zr;
up to about 0.015 wt % B;
about 0.4 to about 1.2 wt % Mn;
about 0.1 to about 0.3 wt % Si; and
balance Ni.
Another embodiment of the present invention is drawn to a repaired turbine engine component having a repaired region and an in-tact region. The repaired region has a composition as provided above.
REFERENCES:
patent: 4101713 (1978-07-01), Hirsch et al.
Beltran Adrian Maurice
Frost Aaron Todd
Jackson Melvin Robert
Mukira Charles Gitahi
Johnson Noreen C.
Look Edward K.
McAleenan James M
Stoner Douglas E.
LandOfFree
Superalloy weld composition and repaired turbine engine... does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Superalloy weld composition and repaired turbine engine..., we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Superalloy weld composition and repaired turbine engine... will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2851919