Dust and dirt, condensates, lubricants and oils must be thoroughly removed. If the metal work pieces are poorly prepared, the flux will not spread evenly and the flow of filler alloy will be haphazard: it will either not spread properly or will discolour. The consequence would be an incomplete joint. The first step is therefore: […]
When brazing aluminum to stainless steel using: a) NOCOLOK® Flux and Al-Si filler alloys are suitable or b) alternatively CsAlF-Complex flux (melting range between 420 and 480°C) and Zn-Al filler alloys. Regarding a): Brazing of aluminum to stainless steel works both with NOCOLOK® Flux + Al-Si filler alloy and with NOCOLOK® Sil Flux. After the […]
The following article provides some answers on general questions regarding the use of NOCOLOK Sil Flux for manufacturing pots and pans. What is the NOCOLOK Sil Flux quantity (per m²) required for sandwich brazing or pressure cookers (stainless steel to aluminium)? The recommended load for NOCOLOK Sil Flux is approximately 15 to 25 g/m². Brazing aluminium to stainless […]
Brazing sheet comprises of a core alloy clad on 1 or 2 sides with a lower melting aluminum-silicon (Al-Si) alloy. This thin layer, usually makes up 5 % to 10 % of the total thickness of the brazing sheet. It melts and flows during the brazing process, to provide upon cooling a metallic bond between […]
All heat exchanger manufacturers currently using zinc-coated tubes or zinc-coated brazing sheet and extrusions for corrosion protection are invited to consider NOCOLOK® Zn Flux as an alternative. How does NOCOLOK® Zn Flux work? The flux – a fine white powder with the chemical formula KZnF3 – is manufactured by Solvay Fluor similarly to standard NOCOLOK® […]
A new coating technology for the functionalization of semi-finished aluminium products for heat exchanger (HEX) applications has been developed by Erbslöh Aluminium GmbH with assistance from Solvay Fluor. In contrast to binder-based flux coatings, it is now possible to apply various kinds of NOCOLOK® fluxes free of any adhesives for the Controlled Atmosphere Brazing (CAB) […]
For added strength and machineability, certain alloys contain Mg. Most notably are the 6XXX series alloys (up to 1% Mg) that are used for fittings and machined components and the so-called long life brazing sheet alloys (up to 0.3% Mg in the core). There is a limit to the amount of Mg tolerated in NOCOLOK® […]
This increase in efficiency means the same refrigerant capacity can be produced with smaller exchange surfaces at the condenser and evaporator, with an associated reduction in piping volume, i.e. a higher heat exchange efficiency means smaller systems and lower refrigerant charge. Important given that third generation HFC refrigerant blends such as R 410 A are […]
Aluminum alloys are classified according to their alloying elements. The Aluminum Association designations are listed in the table below: Designation System for wrought aluminum alloys Alloys series Description or major alloying element 1xxx 99.00% minimum Aluminum 2xxx Copper 3xxx […]
How to measure? In the case of heat exchangers, the surface area being fluxed must first be determined. For ease of calculation, the louvers on the fin can be ignored. The radius on the fin can also be ignored. Imagine then the fin pulled out of the heat exchanger and straightened out to form one […]