HIGHLY CORROSION-RESISTANT COPPER TUBE
Use of a heat transfer tube in a damp environment in air-conditioning equipment and exposed to corrosive action caused by a corrosive medium comprising at least one lower carboxylic acid, the heat transfer tube a copper tube comprising 0.10-1.0% by weight of P and the balance consisting of Cu and inevitable impurities. The corrosive action progresses in the form of an ants' nest from an outer surface of the heat transfer tube in a direction of its wall thickness, wherein. Also, use of a copper tube comprising 0.10-1.0% by weight of P and the balance consisting of Cu and inevitable impurities for improving corrosion-resistance against ant nest corrosion caused by a corrosive medium consisting of a lower carboxylic acid in a damp environment, method of inhibiting ants' nest corrosion in a heat transfer tube, and a method of positioning a tube in an air conditioning apparatus or a refrigeration apparatus.
1 . Use of a heat transfer tube used in a damp environment in air-conditioning equipment and exposed to a corrosive action caused by a corrosive medium comprising at least one lower carboxylic acid, which corrosive action progresses in the form of an ants' nest from an outer surface of the heat transfer tube in a direction of its wall thickness, wherein the heat transfer tube is a copper tube comprising 0.10-1.0% by weight of P and the balance consisting of Cu and inevitable impurities.
2 . The use of a heat transfer tube as recited in claim 1 , wherein the heat transfer tube comprises not lower than 0.15% by weight of P.
3 . The use of a heat transfer tube as recited in claim 1 , wherein the heat transfer tube comprises not higher than 0.8% by weight of P.
4 . The use of a heat transfer tube as recited in claim 1 , wherein the heat transfer tube comprises not higher than 0.5% by weight of P.
5 . The use of a heat transfer tube as recited in claim 1 , wherein the heat transfer tube comprises 0.3-1.0% by weight of P.
6 . The use of a heat transfer tube as recited in claim 1 , wherein the heat transfer tube comprises not lower than 0.19% by weight of P.
7 . The use of a heat transfer tube as recited in claim 1 , wherein a total amount of the inevitable impurities is not higher than 0.05% by weight.
8 . The use of a heat transfer tube as recited in claim 1 , further comprising operating said air conditioning equipment such that heat is transferred through said heat transfer tube.
9 . The use of a heat transfer tube as recited in claim 1 , wherein corrosion progresses in a direction extending along a surface of the heat transfer tube.
10 . The use of a heat transfer tube as recited in claim 1 , wherein the heat transfer tube was produced by casting an ingot or a billet, and extruding and drawing the ingot or billet.
11 . Use of a copper tube comprising 0.10-1.0% by weight of P and the balance consisting of Cu and inevitable impurities for improving corrosion-resistance against ant nest corrosion caused by a corrosive medium consisting of a lower carboxylic acid in a damp environment.
12 . The use of a heat transfer tube as recited in claim 11 , wherein the heat transfer tube comprises not lower than 0.15% by weight of P.
13 . The use of a heat transfer tube as recited in claim 11 , wherein the heat transfer tube comprises not higher than 0.8% by weight of P.
14 . The use of a heat transfer tube as recited in claim 11 , wherein the heat transfer tube comprises not higher than 0.5% by weight of P.
15 . The use of a heat transfer tube as recited in claim 11 , wherein the heat transfer tube comprises 0.3-1.0% by weight of P.
16 . The use of a heat transfer tube as recited in claim 11 , wherein the heat transfer tube comprises not lower than 0.19% by weight of P.
17 . The use of a heat transfer tube as recited in claim 11 , wherein a total amount of the inevitable impurities is not higher than 0.05% by weight.
18 . The use of a heat transfer tube as recited in claim 11 , further comprising operating said air conditioning equipment such that heat is transferred through said heat transfer tube.
19 . The use of a heat transfer tube as recited in claim 11 , wherein corrosion progresses in a direction extending along a surface of the heat transfer tube.
20 . The use of a heat transfer tube as recited in claim 11 , wherein the heat transfer tube was produced by casting an ingot or a billet, and extruding and drawing the ingot or billet.
21 . A method of inhibiting ants' nest corrosion in a heat transfer tube, the method comprising:
forming a tube having a composition comprising 0.10-1.0% by weight of P and the balance consisting of Cu and inevitable impurities;
positioning the tube in an air conditioning apparatus or a refrigeration apparatus; and
subjecting the tube to a corrosive environment comprising at least one lower carboxylic acid in a damp atmosphere.
22 . A method, comprising:
positioning a tube in an air conditioning apparatus or a refrigeration apparatus;
operating said air conditioning apparatus or refrigeration apparatus such that heat is transferred through said tube; and
exposing said tube to a corrosive medium in a damp environment in said air-conditioning apparatus or said refrigeration apparatus, such that said corrosive medium generates ants' nest corrosion that progresses from a surface of said tube,
said tube comprising 0.10-1.0% by weight of P and the balance consisting of Cu and inevitable impurities.