Atmospheric pressure at sea level is:- a) 1013 mbar b) O bar c) 14.7 bar d) 4.186 bar 10. Wet steam is:- a) Steam that is capable of receiving more 'enthalpy of evaporation' b) Steam with no 'superheat' c) Steam above 100C d) Superheated water . During heat transfer three factors control the amount of enthalpy transferred from steam to the product. These are:- a) Surface area/temperature difference/ coefficient of heat transfer b) Scale film condensate film/ air film c) Product temperature / U-value / steam pressure d) Surface area / specific heat capacity / temperature difference 12.1 mm of air produces an insulating effect equivalent to:- a) 2.0 m water b) 100 mm fibreglass c) 13.2 m thick of copper d) 25 mm cast iron Which one of the following trap types should be used to drain an air heater battery? a) Ball float b) Bi-metallic c) Liquid expansion d) Balanced pressure 14. The name-plate on a mechanical type steam trap shows it is limited to a maximum differential pressure of 4.5 bar. What would be the effect of fitting the trap on a 7 bar system:- a) No effect b) Trap will be damaged c) Trap will close and not open again d) Trap will not close 15. Which one of the following trap types should not be used where plant being drained is subject to changes of pressure and fluctuating steam load? a) Inverted bucket b) Bi-metallic c) Thermodynamic d) Ball float 16. A balanced pressure thermostatic steam trap operates:- a) By accurately following the steam saturation curve b) By following a series of straight lines that approximates the steam saturation curve c) When the condensate temperature is a set number of degrees below steam temperature d) By sensing density of condensate. 1. Drain pockets on 3" steam mains should be:- a) line size 'T' b) 2" taken from top of main c) Small bore taken from bottom of main d) At terminal points only 18. Air in a steam system has the effect of:- a) Raising system temperature b) Lowering system temperature c) Has no effect except insulation d) Lowers system pressure 18. Which pair of steam traps discharge condensate immediately it forms? a) TD and inverted bucket b) Float trap and inverted bucket c) Balanced pressure and float trap d) TD and balanced pressure 20. Which of the following types of trap vents air most efficiently? a) Simple float and lever trap b) Inverted bucket trap c) Balanced pressure trap d) Thermodynamic trap . A steam trap should be sized:- a) To handle the running load b) Line size c) Twice normal running load (subject to application) d) To take into account flash steam 32. A steam trap discharges condensate from a steam main operating at 7 bar gauge into a condensate main operating at 3 bar gauge. What is the differential pressure across the trap? a) 7 bar b) 4 bar c) 10 bar d) 3 bar 28. A steam main is fed with steam at 20 bar gauge. A branch is taken off the main to feed a critical process operating at 2 bar gauge but where the load fluctuates from maximum to almost zero at irregular intervals. What type of valve should be fitted to control the pressure of the process? a) Pilot operated reducing valve b) Direct acting reducing valve c) Globe valve d) Electric gear actuator 24. Steam at 9 bar gauge with a dryness fraction of 0.93 is passed through a pressure reducing valve to a pressure of 4 bar gauge. What is the condition of the steam at this reduced pressure? a) 0.9 b) 0.85 c) Superheated d) 0.95 25. Which of the diagrams below shows a correctly installed pressure reducing station? a) b) c) 26. A heat exchanger operates at 6 bar gauge and discharges through a float trap into a condensate return system pressurised to 1 bar gauge. Approximately how much flash steam is released per kg of condensate discharged from the heat exchanger. a) 190 g b) 85 g c) 93 g d) 70 g 27. In question 26 what will be the temperature of the condensate being discharged from the float trap? a) 100C b) 120C c) 140C d) 165C 28. A heating (non-storage) calorifier is supplied with dry saturated steam at 5.5 bar gauge to heat water from 65C to 80C. If the heating pump has a throughput of 180 litres per minute how much steam will be condensed per hour? a) 3 200 kg b) 187.6 kg c) 752 kg d) 326 kg 29. Vacuum conditions can exist in temperature controlled plant. This can happen when:- a) Modulating controls are used and valve closes b) Outside air temperature drops c) Steam demand drops d) Insufficient steam supply pressure 20. Where should a sight glass be fitted in a thermodynamic trapping set? a) Close-coupled upstream b) Immediately downstream c) Sight glass not necessary d) 1 m downstream d)