SECO/WARWICK Heat Processing EquipmentFurnace Parts, Service, Repair, Upgrade, Relocate
SECO/WARWICK CorporationAluminum Furnaces, Preheat, Annealing and HomogenizingControlled Atmosphere Brazing, CAB & CuproBrazeSolution Heat Treat FurnaceReverb Melting & HoldingThermal Process - Heat Treating EquipmentVacuum Furnace Technology
CAB Conference & Seminar | Heat Treating Data Book | News Center 
Radiation CAB Aluminium Brazing Furnace
Active Only CAB Aluminum Brazing Convection CAB Brazing

Controlled Atmosphere Aluminum Brazing (CAB)

Click here for Spanish - Español

News

Information

Staff Directory

RFQ Form

Maintenance Tips

Español

CAB Brazing is used in both automotive and HVAC manufacturing for brazing radiators, condensers, oil coolers, evaporators, heaters and charge air coolers.  NOCOLOK® Brazing was originally developed by Alcan as a non-corrosive flux brazing process for heat exchangers. Today, NOCOLOK is the trademark for Solvay Fluor GmbH flux products, but remains the common name for the CAB process. Along with aluminum brazing, we offer CuproBraze® copper-brass brazing technology, a process for heavy duty truck and off-road radiators & charge air coolers.

We can provide the complete CAB Brazing manufacturing cell, follow these quick links for more information:

CAB Brazing Process Preparing the Product Furnace DesignsMore Options

Missed this year's CAB Brazing Seminar? Click here for recap and answers to attendee questions

Looking for something specific? Use Google custom search for fast results:

Google Custom Search

News

Follow SECO/WARWICK on Twitter

Metal Minutes Newsletter is issued quarterly by SECO/WARWICK to publish news, information, case studies and maintenance tips. Stay up-to-date on SECO/WARWICK's global product teams and get valuable insight into current trends in heat treatment equipment.
Click here to Join Our Mailing List

Return to Top

 

Information

Click on the links underlined in blue for specific information,
Click the "Back" Button or the Logo to return to this page

CAB Brazing - Aluminum Brazing with Flux

Aluminium Braze Joint

Controlled Atmosphere Brazing was developed by Alcan, under their trade name NOCOLOK®, as a non-corrosive flux brazing process and is now established as the accepted process for brazing of aluminum heat exchangers.

Aluminum brazing involves joining of components with a brazing alloy (cladding) whose melting point is appreciably lower than that of the parent material (base alloy). The cladding is typically placed adjacent to or in between the components to be joined and the assembly is heated to a temperature where the cladding material melts and the parent material does not. Upon cooling, the cladding forms a metallurgical bond between the joining surfaces of the component.  The brazing process occurs in a furnace under the following parameters:

Operating Temperature 580 degrees C to 620 degrees C

Part Temperature Uniformity of ± 3 degrees C

Oxygen free, Nitrogen Atmosphere of -40 degrees C and 100 ppm of O2 content

In automotive heat exchanger applications, the cladding is supplied via a thin sheet on the base alloy. The base alloy provides the structural integrity while the low melting point cladding melts to form the brazed joints.

Why the need of flux? Once the flux is molten inside the furnace, the flux works to dissolve the tenacious oxide layer that is present on the aluminum surface and prevent further oxidation. By dissolving this oxide layer the flux wets the faying surface of the components to be joined allowing the filler metal (cladding) to be drawn freely into the joints by capillary action. Upon cooling the flux remains on the surface as a thin film.

During furnace brazing, a brazing sheet, fig. 2, of aluminum silicon alloy plate (cladding) is heated to a liquid state and flows to form aluminum joints or fillets.  A sample fillet is shown in fig. 3

Getting the Product Ready for Processing

Thermal Degreasing System Flux Application System

Dry Off Oven

Cleaning

In order for proper brazing to occur, the products must be prepared for brazing. The first step is to clean the products of all oils, dirt, etc. prior to the fluxing process. This can be accomplished by utilizing a Thermal Degreasing Oven or an Aqueous Washer.

Flux Application Methods

After the products are cleaned, a wet flux slurry is applied to the core by means of spraying for external coverage and dipping for internal coverage. The flux is mixed into a slurry form using treated water or de-ionized water, which prohibits natural salts from being deposited on the heat exchanger.

Dry Off Oven

The dry off oven is the final preparation before brazing. The purpose of the dry off oven is to remove the water present from the fluxing stage so that the heat exchanger is free of moisture prior to entering the braze furnace.

Furnace Design Selection

Radiation CAB Aluminium Brazing Furnace Radiation/Convection CAB Aluminium Brazing Furnace

Convection CAB Aluminium Brazing Furnace

Radiation Furnace
Style: Continuous

A Radiation CAB Furnace is an ideal method for brazing similar size products in a continuous flow environment. If you intend to produce a single or only a few variations of that product, a radiation furnace system makes sense.

Radiation w/Convection Preheat
Style: Continuous

When your brazing needs are more diverse, a combination of convection preheating and radiation brazing improves the furnace's overall flexibility, enabling manufacturers to braze products of different mass and dimensions without changing the furnaces set point parameters.

Convection Furnace
Style: Continuous

A pure convection heated furnace is the most efficient means to braze a wide variety of heat exchangers in the shortest possible cycle time. Convection heating is the best means to bring the entire heat exchanger (fins, tubes, headers) to brazing temperature in the recirculated nitrogen atmosphere.

Active Only CAB Aluminium Brazing Furnace Vacuum Purge CAB Aluminum Brazing Furnace

Vertical CAB Aluminium Brazing Furnace

Active OnlyŽ
Style: Semi-continuous

The Active Only Semi-Continuous CAB Aluminum Brazing Furnace system is an indexing furnace designed to meet the needs of aftermarket manufactures or companies that have a wide variety of production needs from day to day. The furnace is designed to braze 3 to 5 load areas per hour on a semi-continuous basis.

Vacuum Purge
Style: Batch

The vacuum purge batch CAB furnace is an advanced hot wall, front loading retort furnace with vacuum purging especially designed for CAB brazing. The standard furnace hot zone is 600 mm x 600 mm x 900 mm, however SECO/WARWICK can custom engineer furnaces to suit the application This system is ideal for R & D projects.

 

Vertical Furnace
Style: Batch

A variation of the Active Only® furnace system is an electrically heated batch furnace with heating elements positioned horizontally. For certain applications, this product orientation improves the cladding melting process. Vertical positioning of the heat exchanger allows the joints to be evenly filled on a horizontal plane. This prevents the brazing alloy from accumulating on one side of the heat exchanger

Precision Controls, Quality Muffles

 

ACCUBRAZE CAB Aluminium Brazing Control SystemACCUBRAZE® Control System

Convection heating with accurate temperature control and uniformity are essential when running loads with varying masses and configurations one after another. The braze furnace is controlled by a PC/PLC based system utilizing ACCUBRAZE software developed by the SECO/WARWICK.

 

 

CAB Aluminium Brazing Furnace MuffleCAB Furnace Muffles

SECO/WARWICK began to design and manufacture muffles in-house in 1995 after rejecting poor quality work and long lead times from outside sources. We recognized that we could build a better quality muffle in our plant, providing customers with better value and expedited delivery.   Today, SECO/WARWICK maintains the engineering intelligence for both SECO/WARWICK and Camlaw brand controlled atmosphere brazing furnace muffles.  SECO/WARWICK has the technical expertise and original drawings to provide you with a muffle that will correctly fit your furnace.

Aluminum Brazing Product Brochure , .pdf format

Brochure BZ-134.2 CAB Brazing Systems, our complete product line of CAB furnaces (English)

Return to Top

CuproBraze Technology Information

Copper Brass Radiator processed in CuproBraze technology CuproBraze® copper-brass brazing technology, a process ideally suited for heavy duty truck and off-road radiators & charge air coolers.

Click here for product information in .pdf format (English)

Visit the website developed by the experts in the
CuproBraze Process at www.cuprobraze.com (English)

 

Return to Top


SECO/WARWICK CAB Brazing

P. O. Box 908 180 Mercer Street Meadville, PA 16335-6908  USA
Phone (814)332-8400 - Fax (814)724-1407
info@secowarwick.com

©1995-2009 SECO/WARWICK Corporation All Rights Reserved.

Return to top  | Return to Home |