LANCE FOR HEATING OR CERAMIC WELDING

摘要

Lance apparatus employed for either heating purposes or for ceramic welding purposes, such as applying a heating flame to a surface followed by spraying sand or like solid particulate material in a combustion-supporting carrier gas to the surface, comprises a single tubular lance having a tip end and a butt end and having a head portion (10+20) with a central main bore at the tip end, whereby ceramic welding materials comprising particulate material containing oxidisable particles and combustion-supporting carrier gas are introduced at the butt end, pass through the main bore (13+23) and emerge at the tip, characterised in that the head portion further comprises at least one conduit (28) to convey a mixture of a fuel gas and a combustion-supporting gas, each such conduit (28) having an orifice (29) at the tip of lance and being provided with a portion (28a) for the introduction of fuel gas and a portion (28b) for the introduction of combustion-supporting gas, whereby fuel gas and combustion-supporting gas introduced at the butt end combine in the conduit (28) and emerge to form a flame at the tip end of the or each conduit. The lance permits the application to the surface of an intense high pressure flame, immediately followed by the ceramic welding activity.