Abstract: A torque shaft assembly includes a hollow tube with a central axis disposed between and fixedly connected to first and second crankshafts at first and second distal ends, respectively, of the tube for movement of an array of connecting members such as push rods. A hollow interior of tube between the first and second crankshafts is filled with a sufficient quantity of flowable inertia material or damping media to absorb vibratory energy by friction during operation of the engine. The hollow interior is preferably filled with a quantity of damping media to a level by volume of about 98% and a preferred flowable inertia material is round steel shot. A plurality of spaced-apart clevises are fixedly attached to a tube wall on an outer surface of the tube wall surrounding the hollow interior. Each clevis includes connection means disposed away from the wall outer surface for connection with an actuator for movement of the array of adjustable devices such as variable stator vanes.

Abstract: A method of repairing a gas turbine engine compressor blade airfoils includes machining away airfoil material along leading and trailing edges and a radially outer tip of the airfoil to form leading edge, trailing edge, and tip cut-backs. Then beads of welding material are welded onto the leading edge, trailing edge, and tip cut-backs. Then some of the weld material is machined away from the weld bead to obtain desired finished dimensions of the leading and trailing edges and radially outer tip. Blade material along only radially outermost portions of the leading and trailing edges extending from the tip towards a base of the airfoil is machined away. A rounded corner is formed between the leading edge and trailing edge cut-backs and unmachined portions of the airfoil between the outermost portions of the leading and trailing edges and the base of the airfoil.

Abstract: A method of repairing a gas turbine engine compressor blade airfoils includes machining away airfoil material along leading and trailing edges and a radially outer tip of the airfoil to form leading edge, trailing edge, and tip cut-backs. Then beads of welding material are welded onto the leading edge, trailing edge, and tip cut-backs. Then some of the weld material is machined away from the weld bead to obtain desired finished dimensions of the leading and trailing edges and radially outer tip. Blade material along only radially outermost portions of the leading and trailing edges extending from the tip towards a base of the airfoil is machined away. A rounded corner is formed between the leading edge and trailing edge cut-backs and unmachined portions of the airfoil between the outermost portions of the leading and trailing edges and the base of the airfoil.

Abstract: An article and a method for improving an article that results in a reduction or elimination of damage due to fretting from contact of similar metals. The invention specifically reduces wear-related fretting between titanium alloy parts by lowering the stresses between mating parts. An aluminum bronze coating is applied to one of the parts. The aluminum bronze coating provides an improvement over prior art coatings in reducing coefficient of friction between the parts. Additionally, the cumulative stresses at the surface of the parts is reduced by a dual intensity peening treatment. This involves a first peening operation using large peening media that provides a compressive stress to the required depth. This first peening operation is followed by a second peening operation that provides additional compressive stresses closer to the dovetail surface.

Abstract: A dovetail of a rotor blade is mounted in a complementary slot in a rotor disk. Life of the dovetail is simulated by providing a specimen dovetail mounted in a complementary slot in a fixture. Relative stiffness of the specimen dovetail and fixture are tailored to simulate the loading profile between the blade dovetail and rotor disk. Load is cycled between the specimen dovetail and fixture for determining life of the dovetail.

Abstract: A rotor blade includes an airfoil, an integral platform, and a dovetail integrally joined to the platform. The dovetail includes a neck extending between a pair of dovetail lobes configured to engage a complementary slot in a rotor disk. The dovetail includes an undercut extending between an outer face of the dovetail lobes and the neck for introducing a stress concentration thereat. The stress concentration relieves stress at the outer face at the expense of the neck for increasing the high cycle fatigue life of the blade.