Dry gas seal system

An axial end face separation seal for a dry gas seal system for rotating equipment operating on a process fluid, the separation seal comprising a primary ring, a mating ring, a sleeve for coupling the mating ring to the shaft of the rotating equipment during operation, and a retainer for the primary ring;

• wherein the separation seal includes an oleophobic coating disposed at least partially over each of the following surfaces of the separation seal:
• a) at an outer peripheral edge of the primary ring distal to, and facing away from, the shaft of the rotating equipment during operation;
• b) at an outer peripheral edge of the mating ring distal to, and facing away from, the shaft of the rotating equipment during operation;
• c) both surfaces of the mating ring and primary ring which interface with each other during operation.

A method for providing a coated axial end face separation seal for a dry gas seal system for rotating equipment operating on a process fluid, said method comprising:

• i) providing a primary ring, a mating ring, a sleeve for coupling the mating ring to the shaft of the rotating equipment during operation, and a retainer for the primary ring;
• ii) providing an oleophobic coating at least partially over each of the following surfaces of the separation seal:
• a) at an outer peripheral edge of the primary ring distal to, and facing away from, the shaft of the rotating equipment during operation;
• b) at an outer peripheral edge of the mating ring distal to, and facing away from, the shaft of the rotating equipment during operation;
• c) both surfaces of the mating ring and primary ring which interface with each other during operation;
• and
• iii) assembling the primary ring, mating ring, sleeve, and retainer to form the coated separation seal.