GB490370A - Improvements in or relating to gas burners for gas-fired tubular boilers and heaters - Google Patents

Abstract

490,370. Pilot jets. GRATER, N. Feb. 12, 1937, No. 4162. [Class 75 (iii)] In burners for gasfired tubular boilers and heaters of the kind comprising one or more gas passages having a plurality of nozzles for projecting flames into the open ends of the combustion tubes of the boiler &c., a pilot jet is directed through each nozzle for maintaining a flame when the main gas supply is shut off. As shown in Fig. 1, a header a is divided by a partition a<1> for supplying gas through main risers d to inlets o in the 'nozzles i and through auxiliary risers g to pilot jets n in the inner ends of the nozzles. Each nozzle has a cylindrical extension j provided with air holes k. A snap-action valve is provided to shut off the gas supply to the main space of the header. When the valve is open, the nozzles are supplied substantially entirely through the risers d. On closing the valve, gas issues from the pilot jets i into the nozzles to maintain the flames. An adjustable byepass may be provided to keep the header full of gas when the valve is closed. In a modification, a pilot jet s, Fig. 2, projects into the nozzle p, which secures a shield q. The header a may be provided with a central pilot-header tube, instead of the partition a<1>, to act as a stay.