Method and apparatus for reducing stress on the tips of turbine or compressor blades

A method of maintaining blade fatigue strength in a turbine engine wherein the blade contacts a circumferential seal, comprising the steps of:

• (a) providing a blade having a blade tip including a leading edge, a trailing edge, opposing surfaces, and a center portion defined by the leading and trailing edges and opposing surfaces;
• and
• (b) applying an abrasive coating to the center portion of the blade tip so that a peripheral edge of the abrasive coating remains set back from the opposing surfaces of the blade tip and extends at least partially between the leading and trailing edges, said abrasion resistant coating extending further than the blade tip.

A method of maintaining blade fatigue strength in a turbine engine wherein the blade contacts a circumferential seal, comprising the steps of:

• (a) providing a blade having a base and a tip, the tip including leading and trailing edges, opposing surfaces, and a center portion defined by the leading and trailing edges and opposing surfaces;
• and
• (b) chamfering at least a portion of both of the opposing surfaces at intersections between the opposing surfaces and the center portion of the tip of the blade where a high stress exists so as to reduce stress at the tip of the blade when the blade is used in a turbine engine.

A blade for use in a turbine engine wherein the blade contacts a circumferential seal, the blade comprising:

• (a) a base and a tip, the tip including leading and trailing edges, opposing surfaces, and a center portion defined by the leading and trailing edges and opposing surfaces;
• and
• (b) a chamfer disposed on at least a portion of both of the opposing surfaces at intersections between the opposing surfaces and the center portion where a high stress exists.

A method of maintaining blade fatigue strength in a turbine engine wherein the blade contacts a circumferential seal, comprising the steps of:

• (a) providing a blade having a base and a tip, the tip including leading and trailing edges, opposing surfaces, and a center portion defined by the leading and trailing edges and opposing surfaces;
• and
• (b) chamfering at least a portion of one or more of the opposing surfaces at an intersection beginning behind the leading edge and terminating ahead of the trailing edge between the opposing surfaces and the center portion of the tip of the blade where a high stress exists so as to reduce stress at the tip of the blade when the blade is used in a turbine engine.

A blade for use in a turbine engine wherein the blade contacts a circumferential seal, the blade comprising:

• (a) a base and a tip, the tip including leading and trailing edges, opposing surfaces, and a center portion defined by the leading and trailing edges and opposing surfaces;
• and
• (b) a chamfer disposed at an intersection of at least one of the opposing surfaces and the center portion where a high stress exists and extending at least partially between the leading and trailing edges, wherein the chamfer begins behind the leading edge and terminates ahead of the trailing edge.