ASME SECTION VI-2008 pdf download.RECOMMENDED RULES FOR THE CARE AND OPERATION OF HEATING BOILERS.
(3) sectional header: a horizontal boiler ofthe lon- gitudinal or cross drum type, with the tube bank composed of multiple parallel sections, each section made up of a front and rear header connected by one or more vertical rows of generating tubes and with the sections or groups of sections having a common steam drum. (4) boxheader: ahorizontal boilerofthe longitudi- nal or cross drum type consisting of a front and a rear inclined rectangular header connected by tubes. (5) cross drum: a sectional header or box header boiler in which the axis of the horizontal drum is at right angles to the center lines of the tubes in the main bank. (6) longitudinal drum: a sectional header or box header boiler in which the axis of the horizontal drum or drums is parallel to the tubes in a vertical plane. (7) low head: a benttube boilerhaving three drums with relatively short tubes in the rear bank. (b) firetube: a boiler with straight tubes that are sur- rounded by water and steam and through which the prod- ucts of combustion pass. (1) horizontal return tubular: a firetube boiler con- sisting of a cylindrical shell, with tubes inside the shell attached to both end closures. The products of combustion pass under the bottom half of the shell and return through the tubes. (2) locomotive: a horizontal firetube boiler with an internal furnace, the rear of which is a tubesheet directly attached to a shell containing tubes through which the products of combustion leave the furnace. (3) horizontal firebox: a firetube boiler with an internal furnace the rear of which is a tubesheet directly attached to a shell containing tubes. The first-pass bank of tubes is connected between the furnace tubesheet and the rear head. The second-pass bank oftubes, passing over the crown sheet, is connected between the front and rear end closures.
(c) modular: a steam or hot water heating boiler assembly consisting of a grouping of individual boilers called modules, intended to be installed as a unit, with a single inlet and a single outlet. Modules may be under one jacket or individually jacketed. (d) vacuum: afactory-sealedsteamboilerthatis oper- ated below atmospheric pressure. (e) boiler, steam heating: a boilerdesignedto convert water into steam, that is supplied to an external space heating system. (f) boiler, hotwaterheating: a boiler designed to heat water for circulation through an external space heating distribution system. (g) boiler, hot water supply: a boiler used to heat water for purposes other than space heating. boiler horsepower: the evaporation of 34.5 lb (15.6 kg) of water per hour from a temperature of 212°F (100°C) into dry saturated steam at the same temperature equivalent to 33,475 Btu/hr (9.8 kW). boiler inspection: boilers that are fabricated are usually inspected during construction for compliance with Code design requirements. They are also periodically field inspected internally and externally for corrosion or scaling andfortheconditionofcontrols, safetydevices, etc. Boilers that are cast are given a hydrostatic test only (each section or the complete boiler); a visual inspection by the Author- ized Inspector is not required unless local jurisdictions require periodic field inspections. boiler layup: any extended period of time during which the boiler is not expected to operate and suitable precau- tions are made to protect it against corrosion, scaling, pit- ting, etc., on the water and fire sides. boiler trim: piping on or near the boiler that is used for safety, limit, and operating controls, gages, water col- umn, etc.