DC Boiler Exam Prep 2015 Study online at https://quizlet.com/_19dkt7 1. Area of a rectangle Length x Width 2. Area of a Circle .7854 x Diameter² 3. Volume of a Box Length x Width x Height 4. Volume of a Cylinder .7854 x Diameter² x Length 5. Circumference of a Circle À x Diameter 6. Unit of Force Pound (lb) 7. Formula for Force Pressure ÷ Area 8. Unit of Work in-lb or ft-lb 9. Formula for Work Force x Distance 10. Unit of Power ft-lb/min 11. Formula for Power = Work ÷ Time or (Force x Distance) ÷ Time 12. Formula for Mechanical Horsepower = Power ÷ 33,000 ft-lb/min 13. Fahrenheit to Celsius °C = (°F - 32) ÷ 1.8 14. Celsius to Fahrenheit °F = (1.8 x °C) - 32 15. Fahrenheit to Rankine °R = °F + 460 16. Celsius to Kelvin K = °C +273.15 17. Charles' First Law Volume1 / Pressure1 = Volume2 / Pressure2 18. Charles' Second Law Pressure1 / Temperature1 = Pressure2 / Temperature2 19. Boyle's Law 1 / 20 DC Boiler Exam Prep 2015 Study online at https://quizlet.com/_19dkt7 Pressure1 x Volume1 = Pressure2 x Volume2 20. General Gas Law (Pres1 x Vol1)/ Temp1 = (Pres2 x Vol2)/Temp2 21. Formula for Levers Resistance x DistanceR = Effort x DistanceE 22. Formula for Inclined Planes Force x Length = Resistance x Height 23. Formula for Wheel & Axel Force x DistanceF = Resistance x DistanceR 24. Torque Force x Radius 25. Safe Working Pressure of a Riveted Boiler (SWP) (Area of Staybolt x Stress Constant of Staybolt) ÷ Area Covered by Staybolt or = (a x C) ÷ A 26. Area Covered by Staybolt = Pitch x Pitch 27. Longitudinal Stress (P x D x L) / 2t P = Pressure D = Diameter L = Length t = thickness of steel 28. Boiler Heating Surface (tubes) = = C x L x # C = Circumference of tubes L = Length of tubes # = Number of tubes HS = À x Diameter x Length x Number of Tubes 29. Watts per Boiler Horsepower 746 Watts 30. Horsepower formula = ft-lb/min ÷ 33000 ft-lb/min 31. ft-lb formula for a pump = gpm x 8.33 x head (ft) 2 / 20 DC Boiler Exam Prep 2015 Study online at https://quizlet.com/_19dkt7 32. Factor of Evaporation (FE) = = [Hs - (tfw-32)] ÷ 970.3 Hs = Enthalpy of steam tfw = temperature of feed water 33. Latent Heat of Vaporization for Water 970.3 Btu/lb 34. Latent Heat of Fusion for Water 144 Btu/lb 35. 1 Boiler Horsepower = x lbs of steam generator per hour 34.5 lbs/hr 36. 1 Boiler Horsepower = x Btu/hr 33,475 Btu/hr 37. 1 BHP = x ft² of heating surface (general) 10 ft² heating surface 38. Volume of water increases by x percent when it flashes to steam x 1600 39. Thermal Efficiency (TE) = = Lbs Steam per hour [Hs -(fwt° -32)] ÷ Units of Fuel per hour x Btu content per unit of fuel Hs = Btu content of steam fwt = feed water temperature