GB863281A - Improvements in welding fluxes - Google Patents

Abstract

A submerged arc welding flux consisting of free-flowing granules produced otherwise than by fusion includes an ore and a deoxidizer which react in the heat of the arc to form an alloying element in metallic form. The ore may be hausmannite, chromite or molybdic oxide and the deoxidizer may be carbon, ferro-silicon, calcium silicide, calcium-silicon or magnesium-aluminium. The flux may comprise two sets of granules one including the deoxidizer and the ore and the other containing the other ingredients. A metal powder, e.g. iron, nickel, cobalt or copper, in which the alloying element is soluble may be included. A flux for welding mild steel with a mild steel electrode is: 100 limestone, 300 china clay, 75 fluorspar, 70 manganese ore, 10 anthracite, 20 ferrosilicon (50% Si), 5 aluminium powder. The flux is granulated with water as described in Specification 847,965 and fired at a minimum of 1000 DEG C. for 5-20 minutes. Another flux for similar use is: 300 manganese ore, 120 sand, 5 graphite, 30 ferrosilicon (50% Si), which is granulated with a 2% calcium chloride solution in water as described in Specification p 863,072 and fired at 1100 DEG C. for 5-20 minutes. A flux for welding stainless steel using an 18/8 stainless steel electrode is: 300 rutile, 180 magnesia, 100 ball clay, 40 niobium ore, 50 chromite, 80 ferro-titanium, 50 fluorspar, and is granulated with a 2% solution of gum acacia as described in Specification 863,072 and kilned for 30 minutes at 700 DEG C. A flux for mild steel consists of: Part 1 300 manganese ore, 90 sand, 25 ferro-silicon (50% Si), 20 cast iron powder, 5 anthracite, granulated with 1% sodium carboxymethyl cellulose solution and Part 2 110 sand, 20 fluorspar, 30 ball clay granulated with water. The two parts are kilned at 1100-1200 DEG C. for 5-15 minutes and mixed. Another flux for mild steel is: Part 1 100 limestone, 350 ball clay, 20 fluorspar, 20 manganese ore granulated with water and: Part 2 50 manganese ore, 20 ferro-silicon, 5 aluminium granulated with a 1% sodium carboxymethyl cellulose solution. The two parts are mixed and kilned at 1100 DEG C. for 5-15 minutes. The above compositions are in parts by weight. Specifications 734,929 and 847,966 also are referred to.