US 4,901,907 A · Heat exchanger core made of aluminum and method for application of flux during process of soldering thereof

Abstract

A method for production of a heat exchanger is disclosed, where a powder flux is applied in a process of soldering a heat exchanger core of aluminum. An annular groove is formed in a seat plate. Measures are taken for preventing wetting of the annular groove of the seat plate when sprayed with the water on the preassembled core, such that a non-corrosive flux would not adhere to the annular groove of the seat plate. Water is sprayed in the form of a mist on a preassembled heat exchanger core through plurality of spray nozzles. The annular grooves of the seat plates are thoroughly dried after the application of water for attaining a perfect absence of residual non-corrosive flux in the annular grooves of the seat plates. A non-corrosive flux powder is sprayed onto the preassembled heat exchanger core of aluminum with a powder spray gun. The non-corrosive flux is caused to adhere fast to the portion wetted with the water.

Claims15

Dependent claims

A method for the application of flux in a process of soldering a heat exchanger core of aluminum including the steps of

(1) alternately disposing tubes and fins, wherein tubes and fins are formed of aluminum material and wherein the tubes and fins are coated on their surfaces with an oven soldering material;
and
(2) placing simultaneously seat plates at opposite ends of said tubes, wherein the seat plates are coated on their surfaces with an oven soldering material and wherein the seat plates are formed of aluminum material thereby forming a preassembled core;
(3) applying a non-corrosive flux on said core;
(4) heating said core in an oven thereby soldering the joints between said tubes, fins, and seat plates;
which method is characterized by
(5) spraying water on said preassembled core such as to prevent the sprayed water from landing on annular grooves on tank sides of said seat plates;
(6) spraying said non-corrosive flux in powdery state on said core in such a manner as to prevent the sprayed flux from landing on said annular grooves on tank sides of said seat plates;
and
(7) drying the wet preassembled heat exchanger core after the spraying and after completion of the application of the non-corrosive flux powder;
(8) subjecting the preassembled heat exchanger now coated with the non-corrosive flux to a soldering treatment in an oven after completion of the drying step.

8 more elements

A method for the application of flux in a process of soldering a heat exchanger core of aluminum comprising the steps of

(1) forming an annular groove in a seat plate;
(2) taking measures for preventing wetting of the annular groove of the seat plate when sprayed with the water on a preassembled core including tubes with fins and seal plate, such that a non-corrosive flux would not adhere to the annular groove of the seat plate;
(3) spraying water in the form of a mist on a preassembled heat exchanger core through a plurality of spray nozzles;
(4) spraying a non-corrosive flux in a powdery state onto the preassembled heat exchanger core of aluminum with a powder spray gun;
(5) causing the non-corrosive flux to adhere fast to the portion wetted with the water sprayed in the preceding step by this non-corrosive flux spraying, and causing the non-corrosive flux substantially not to adhere to the non-wet portion of the preassembled heat exchanger core;
(6) retaining the non-corrosive flux on the surface onto which it is deposited based on the powdery state of the non-corrosive flux.

3 more elements

Dependencies are inferred from the claim text.

Heat exchanger core made of aluminum and method for application of flux during process of soldering thereof

Life of this patent

Heat exchanger core made of aluminum and method for application of flux during process of soldering thereof

Life of this patent

Abstract

Claims15