US Patent 10975905 Packing nut locking apparatus and methods

Aspects of the present disclosure relate to packing nut locking apparatus and methods for fluid ends, and associated components thereof. In one implementation a fluid end apparatus includes a fluid end body having an outer surface, and one or more stay rods disposed at least partially externally to the outer surface of the fluid end body. The fluid end also includes one or more packing nuts, and a lock assembly. The lock assembly includes a first block in contact with the one or more stay rods, and a second block in contact with the one or more packing nuts.