Dragline chain

Abstract

A method for maintaining a chain or chain link comprises inspecting the chain or chain link for signs of wear without using tools and changing the orientation of the chain or chain link or replacing the chain or chain link if signs of wear are detected.

What is claimed is: 
     
       1. A chain link comprising:
 a body including two end portions and two middle portions connecting the two end portions together, 
 wherein at least one middle portion defines at least one region including at least one wear indicator, 
 wherein the body defines a center of mass and a Cartesian coordinate system with an X-axis, Y-axis, a Z-axis and an origin positioned at the center of mass, the end portions define a load vector for the body of the chain link and the X-axis of the coordinate system is oriented parallel with the load vector, and the at least one middle portion defines a first surface defining a first surface normal that is non-parallel to the X-axis, the Y-axis, and the Z-axis, and 
 the at least one wear indicator is disposed on the first surface, and 
 wherein the first surface normal is non-parallel to the Z-axis and the Y-axis, and includes a first pocket defined by the first surface. 
 
     
     
       2. The chain link of  claim 1 , wherein the at least one wear indicator includes a first pocket defined by the first surface. 
     
     
       3. The chain link of claim  2  1, wherein the first pocket is elongated along a direction parallel with the Z-axis X-axis defining its maximum dimension oriented along the Y-axis X-axis, the first pocket further defining a width along a direction parallel with the X-axis Y-axis and a depth along a direction parallel with the Y-axis Z-axis. 
     
     
       4. The chain link of  claim 3 , wherein the at least one middle portion defines a second surface defining a second surface normal that is non-parallel to the X-axis. 
     
     
       5. The chain link of  claim 4 , wherein the second surface includes a second wear indicator in the form of a second pocket that is elongated along a direction parallel with the X-axis Z-axis defining its maximum dimension oriented along the X-axis Z-axis, the second pocket further defining a width along a direction parallel with the Y-axis X-axis and a depth along a direction parallel with the Z-axis Y-axis. 
     
     
       6. The chain link of  claim 5 , wherein second the first pocket defines a bottom extremity positioned along a direction parallel with the Z-axis, the first second pocket defines an end extremity positioned along a direction parallel along the Z-axis, the Cartesian coordinate system establishes a first X-Z X-Y plane positioned at the origin of the Cartesian coordinate system and the body of the chain link defines a second X-Z X-Y plane spaced away from the first X-Z X-Y plane that is disposed between the bottom extremity of the second first pocket and the end extremity of the first second pocket. 
     
     
       7. The chain link of  claim 6 , wherein the Cartesian coordinate system establishes a X-Y plane and a Y-Z, plane, and the body of the chain link is symmetrical about the X-Y plane, the first X-Z plane and the Y-Z plane. 
     
     
       8. A chain assembly comprising:
 at least two chain links interconnected with each other; and 
 at least one of the chain links includes
 a body including two end portions, wherein at least one end portion defines a bite region including a bite contact surface configured to contact the other chain link and that defines a load vector, the at least one end portion including a first portion with a reduced cross-section defining a first thickness measured along a direction that is non-parallel to the load vector, and a raised rib disposed between the bite region and the first portion along a direction parallel with the load vector, the raised rib defining a second thickness along a direction that is non-parallel to the load vector, wherein the second thickness is greater than the first thickness; 
 wherein the body defines a center of mass and a Cartesian coordinate system with an X-axis, Y-axis, a Z-axis and an origin positioned at the center of mass, both the end portions defining a load vector for the body of the at least one of the chain links and the X-axis of the coordinate system is oriented parallel with the load vector, and the body further includes a first middle portion and a second middle portion connecting the two end portions together, forming an enclosed perimeter, and the first middle portion defines a first region including a first wear indicator and a second region including a second wear indicator that has an elongated shape that is perpendicular to the load vector. 
 
 
     
     
       9. The chain assembly of  claim 8 , wherein the body defines a center of mass and a Cartesian coordinate system with an X-axis, Y-axis, a Z-axis and an origin positioned at the center of mass, both the end portions defining a load vector for the body of the at least one of the chain links and the X-axis of the coordinate system is oriented parallel with the load vector, and the body further includes a first middle portion and a second middle portion connecting the two end portions together, forming an enclosed perimeter. 
     
     
       10. The chain assembly of claim  9  8, wherein the at least one end portion defines a first curved portion extending from the first middle portion to the second middle portion and the raised rib extends from the first middle portion to the second middle portion along the first curved portion. 
     
     
       11. The chain assembly of  claim 10 , wherein the body further defines a radiused portion that transitions from the raised rib to the first portion with a reduced cross-section. 
     
     
       12. The chain assembly of claim  9  8, wherein the first middle portion and the second middle portion are straight, extending along a direction parallel to the X-axis. 
     
     
       13. The chain assembly of  claim 12 , wherein the at least one middle portion defines a first region including at least a first wear indicator, and a second region including at least a second wear indicator. 
     
     
       14. The chain assembly of claim  13  12, wherein the first wear indicator has an elongated shape extending in a direction parallel to the load vector and the second wear indicator has a second elongated shape extending in a direction perpendicular to the load vector. 
     
     
       15. The chain assembly of  claim 8 , wherein the first and second thicknesses are measured in a direction perpendicular to the load vector and the ratio of the second thickness to the first thickness ranges from 1.1 to 1.5. 
     
     
       16. The chain assembly of  claim 8 , wherein the at least one end portion defines a first extremity along a direction that is parallel to the load vector and the first portion with a reduced cross-section defines a third thickness measured along a direction that is parallel to the load vector from first extremity to the raised rib, and the raised rib defines a fourth thickness measured along a direction that is parallel to the load vector from the first portion with a reduced cross-section to the bite contact surface, and a ratio of the fourth thickness to the third thickness ranges from 0.30 to 0.50. 
     
     
       17. The chain assembly of claim 12, wherein the at least first wear indicator has an elongated shape extending in a direction parallel to the load vector. 
     
     
       18. A chain link comprising:
 a body including two end portions, wherein at least one end portion defines a bite region including a bite contact surface that defines a load vector, the at least one end portion including a first portion with a reduced cross-section defining a first thickness measured along a direction that is non-parallel to the load vector, and a raised rib disposed between the bite region and the first portion along a direction parallel with the load vector, the raised rib defining a second thickness along a direction that is non-parallel to the load vector, wherein the second thickness is greater than the first thickness; and   the body further includes a first middle portion and a second middle portion connecting the two end portions together, and the first middle portion defines a first region including a first wear indicator and a second region including a second wear indicator that has an elongated shape that is perpendicular to the load vector.   
     
     
       19. The chain link of claim 18, wherein the body defines a center of mass and a Cartesian coordinate system with an X-axis, Y-axis, a Z-axis and an origin positioned at the center of mass, both the end portions defining a load vector for the body, and the X-axis of the coordinate system is oriented parallel with the load vector. 
     
     
       20. The chain link of claim 19, wherein the at least one end portion defines a first curved portion extending from the first middle portion to the second middle portion and the raised rib extends from the first middle portion to the second middle portion along the first curved portion. 
     
     
       21. The chain link of claim 20, wherein the body further defines a radiused portion that transitions from the raised rib to the first portion with a reduced cross-section. 
     
     
       22. The chain link of claim 19, wherein the first middle portion and the second middle portion are straight, extending along a direction parallel to the X-axis. 
     
     
       23. The chain link of claim 22, wherein the at least first wear indicator has an elongated shape extending in a direction parallel to the load vector. 
     
     
       24. The chain link of claim 18, wherein the first wear indicator has an elongated shape extending in a direction parallel to the load vector. 
     
     
       25. The chain link of claim 18, wherein the first and second thicknesses are measured in a direction perpendicular to the load vector and the ratio of the second thickness to the first thickness ranges from 1.1 to 1.5. 
     
     
       26. The chain link of clam 18, wherein the at least one end portion defines a first extremity along a direction that is parallel to the load vector and the first portion with a reduced cross-section defines a third thickness measured along a direction that is parallel to the load vector from first extremity to the raised rib, and the raised rib defines a fourth thickness measured along a direction that is parallel to the load vector from the first portion with a reduced cross-section to the bite contact surface, and a ratio of the fourth thickness to the third thickness ranges from 0.30 to 0.50. 
     
     
       27. A chain link comprising:
 a body including two end portions and two middle portions connecting the two end portions together, wherein at least one middle portion defines at least one region including at least one wear indicator; and   wherein the body defines a center of mass and a Cartesian coordinate system with an X-axis, Y-axis, a Z-axis and an origin positioned at the center of mass, the end portions define a load vector for the body of the chain link and the X-axis of the coordinate system is oriented parallel with the load vector, and the at least one middle portion defines a first surface defining a first surface normal that is non parallel to the Z-axis, and the Y-axis, and a second surface defining a second surface normal that is parallel to the Y-axis.   
     
     
       28. The chain link of claim 27, wherein the at least one wear indicator includes a first pocket defined by the first surface. 
     
     
       29. The chain link of claim 28, wherein the first pocket is elongated along a direction parallel with the X-axis defining its maximum dimension oriented along the X-axis, the first pocket further defining a width along a direction parallel with the Y-axis and a depth along a direction parallel with the Z-axis. 
     
     
       30. The chain link of claim 29, wherein the second surface includes a second wear indicator. 
     
     
       31. The chain link of claim 30, wherein the second wear indicator is in the form of a second pocket that is elongated along a direction parallel with the Z-axis defining its maximum dimension oriented along the Z-axis, the second pocket further defining a width along a direction parallel with the X-axis and a depth along a direction parallel with the Y-axis. 
     
     
       32. The chain link of claim 31, wherein the Cartesian coordinate system establishes a X-Y plane, a X-Z plane, and a Y-Z, plane, and the body of the chain link is symmetrical about the X-Y plane, the X-Z plane and the Y-Z plane.