Refrigeration system connection fitting

1. An aircraft refrigerant system comprising:

a support structure of an aircraft;

a refrigerant circuit supported by the support structure including conduits for communicating a refrigerant between a compressor, a condenser, an expansion valve and an evaporator; and

a connector assembly providing a connection within the refrigerant circuit, the connector assembly including;

a connector including a bore, an end face, a seal bore and external threads, the seal bore open to the bore on a radially inward side;

a nipple including a bore, a shoulder and a seal face;

a securing member including internal threads for engaging the external threads of the connector for holding the end face against the seal face; and

a metal seal received within the seal bore, the metal seal comprising a metal substrate having a coating comprising a metal material different than the substrate that is softer than the metal substrate, the metal seal disposed in sealing engagement with a surface of the seal bore and the seal face.

2. The aircraft refrigerant system as recited in claim 1 , wherein the connector is formed from aluminum, the nipple is formed from stainless steel and the metal seal includes an aluminum coating.

3. The aircraft refrigerant system as recited in claim 2 , wherein the nipple includes an aluminum coating on the seal face and shoulder.

4. The aircraft refrigerant system as recited in claim 1 , wherein the connector and nipple are both formed from stainless steel and the metal seal includes a coating comprising one of a gold and silver material.

5. The aircraft refrigerant system as recited in claim 1 , wherein the seal bore comprises a depth greater than a thickness of the metal seal.

6. The aircraft refrigerant system as recited in claim 1 , wherein the metal seal comprises a substantially disk shaped member.

7. The aircraft refrigerant system as recited in claim 1 , wherein the metal seal is deformable between the seal bore and the seal face of the nipple.

8. The aircraft refrigerant system as recited in claim 1 , wherein the seal face comprises a substantially flat surface transverse to the bore defined through the connector and the nipple.

9. The aircraft refrigerant system as recited in claim 1 , wherein the connector includes a back end attached to a conduit of the refrigerant circuit.

10. A method of installing a refrigerant system within an aircraft comprising:

mounting a refrigerant circuit to a support member of an aircraft;

attaching a connector to a first end of a conduit of the refrigerant circuit, wherein the connector includes a bore and a seal bore concentric with and open to the bore;

attaching a nipple to a second end of a conduit of the refrigerant circuit, wherein the nipple includes a seal face disposed transverse to the bore;

mounting a seal formed of metal within the seal bore defined by the connector; and

securing the nipple to the connector to deform the metal seal within the seal bore for forming a seal between the connector and the nipple.

11. The method as recited in claim 10 , including the step of forming the connector of an aluminum material and the nipple of a stainless steel material, and coating the seal face and shoulder of the nipple with an aluminum coating.

12. The method as recited in claim 10 , including the step of forming an outer surface of the metal seal from an aluminum material.

13. The method as recited in claim 10 , including the step of forming the connector and the nipple of the same material and forming at least an outer surface of the metal seal from material including one of a gold and silver material.