Engineering Bulletin No 1: Boiler and Furnace Testing | Page 8

efficiency because they prevent the heat in the hot gases from getting through into the water. Therefore, keep the shell and tubes free of soot on one side and scale on the other. Soot may be removed by the daily use of blowers, scrapers, and cleaners. The problem of scale and pure feed water is a big one and should be taken up with proper authorities on the subject.
There are many things that may be done to increase the efficiency of the boiler and to save coal. For convenience a number of these points are grouped in the following list:
WHAT TO DO. | WHY. | 1. Close up all leaks in the boiler | To prevent waste of heat due to setting. | excess air admitted. | 2. Keep shell and tubes free from | To allow the heat to pass easily soot and scale. | into the water. | 3. Use grates suited to the fuel | To prevent loss of unburnt coal to be burned. | through air spaces. | 4. Fire often, and little at a | To obtain uniform conditions and time. | better combustion. | 5. Cover all thin spots and keep | To prevent burning holes in bed fire bed level. | and admitting excess air. | 6. Do not allow clinkers to form | Because they reduce the effective on side or bridge walls. | area of the grate. | 7. Keep the ash pit free from ashes | To prevent warping and burning out and hot clinkers. | of the grates. | 8. Do not stir the fire except when | Because stirring causes clinker necessary. | and is likely to waste coal. | 9. Use damper and not ash-pit doors | Because less excess air is to control draft. | admitted by so doing. | 10. See that steam pipes and valves | Because steam leaks waste heat are tight. | and therefore coal. | 11. Keep blow-off valves tight. | Because leaks of hot water waste | coal. | 12. Cover steam pipes and the tops | To prevent radiation and loss of of boilers. | heat.
Make a boiler test under the conditions of operation as they now exist in your plant. Then make all possible improvements as suggested in this bulletin, make another test afterwards and note the increase in the equivalent evaporation per pound of coal used.
Remember that the firing line in the boiler room can be just as patriotic and helpful as the firing line at the front.
Table of factors of evaporation.
============================================================================ Feed | Steam pressure in pounds per square inch, gauge. temperature,|--------------------------------------------------------------- ��F. | 30 | 50 | 70 | 80 | 90 | 100 | 110 | 120 ------------+-------+-------+-------+-------+-------+-------+-------+------- 32 | 1.2073| 1.2144| 1.2195| 1.2216| 1.2234| 1.2251| 1.2266| 1.2279 35 | 1.2042| 1.2113| 1.2164| 1.2184| 1.2203| 1.2219| 1.2235| 1.2248 38 | 1.2011| 1.2082| 1.2133| 1.2153| 1.2172| 1.2188| 1.2204| 1.2217 41 | 1.1980| 1.2051| 1.2102| 1.2122| 1.2141| 1.2157| 1.2173| 1.2186 44 | 1.1949| 1.2020| 1.2071| 1.2091| 1.2110| 1.2126| 1.2142| 1.2155 47 | 1.1918| 1.1989| 1.2040| 1.2060| 1.2079| 1.2095| 1.2111| 1.2124 50 | 1.1887| 1.1958| 1.2009| 1.2029| 1.2048| 1.2064| 1.2080| 1.2093 53 | 1.1856| 1.1927| 1.1978| 1.1998| 1.2017| 1.2033| 1.2049| 1.2062 56 | 1.1825| 1.1896| 1.1947| 1.1967| 1.1986| 1.2002| 1.2018| 1.2031 59 | 1.1794| 1.1865| 1.1916| 1.1937| 1.1955| 1.1972| 1.1987| 1.2000 62 | 1.1763| 1.1835| 1.1885| 1.1906| 1.1924| 1.1941| 1.1956| 1.1970 65 | 1.1733| 1.1804| 1.1854| 1.1875| 1.1893| 1.1910| 1.1925| 1.1939 68 | 1.1702| 1.1773| 1.1823| 1.1844| 1.1862| 1.1879| 1.1894| 1.1908 71 | 1.1671| 1.1742| 1.1792| 1.1813| 1.1832| 1.1848| 1.1864| 1.1877 74 | 1.1640| 1.1711| 1.1762| 1.1782| 1.1801| 1.1817| 1.1833| 1.1846 77 | 1.1609| 1.1680| 1.1731| 1.1751| 1.1770| 1.1786| 1.1802| 1.1815 80 | 1.1578| 1.1650| 1.1700| 1.1721| 1.1739| 1.1756| 1.1771| 1.1785 83 | 1.1548| 1.1619| 1.1669| 1.1690| 1.1708| 1.1725| 1.1740| 1.1754 86 | 1.1518| 1.1588| 1.1638| 1.1659| 1.1678| 1.1694| 1.1710| 1.1723 89 | 1.1486| 1.1557| 1.1608| 1.1628| 1.1647| 1.1663| 1.1679| 1.1692 92 | 1.1455| 1.1526| 1.1577| 1.1597| 1.1616| 1.1632| 1.1648| 1.1661 95 | 1.1424| 1.1495| 1.1546| 1.1566| 1.1585| 1.1602| 1.1617| 1.1630 98 | 1.1393| 1.1465| 1.1515| 1.1536| 1.1554| 1.1571| 1.1586| 1.1600 101 | 1.1363| 1.1434| 1.1484| 1.1505| 1.1523| 1.1540| 1.1555| 1.1569 104 | 1.1332| 1.1403| 1.1453| 1.1474| 1.1492| 1.1509| 1.1525| 1.1538 107 | 1.1301| 1.1372| 1.1423| 1.1443| 1.1462| 1.1478| 1.1494| 1.1507 110 | 1.1270| 1.1341| 1.1392| 1.1412| 1.1431| 1.1447| 1.1463| 1.1476 113 | 1.1239| 1.1310| 1.1360| 1.1382| 1.1400| 1.1417| 1.1432| 1.1445 116 | 1.1209| 1.1280| 1.1330| 1.1351| 1.1369| 1.1386| 1.1401| 1.1415 119 | 1.1178| 1.1249| 1.1299| 1.1320| 1.1339| 1.1355| 1.1370| 1.1384 122 | 1.1147| 1.1218| 1.1269| 1.1289| 1.1308| 1.1324| 1.1340| 1.1353 125 | 1.1116| 1.1187| 1.1238| 1.1258| 1.1277| 1.1293| 1.1309| 1.1322 128 | 1.1085| 1.1156| 1.1207| 1.1227| 1.1246| 1.1262| 1.1278| 1.1291 131 | 1.1054| 1.1125| 1.1176| 1.1197| 1.1215| 1.1232| 1.1247| 1.1260 134 | 1.1023| 1.1095| 1.1145| 1.1166|