AMIE Study Circle Blog

Properties of Steam Problem (Gujarat BOE 2021, 2024, 5 marks) Steam is generated in a boiler at 110 kg/cm 2 at 520 0 C. Assume drum pressure is 118 kg/cm 2 . Using steam table, find: 1. Saturated steam temperature. 2. Degree of superheat. 3. Enthalpy of steam. Solution (i) From the steam table, saturated temperature corresponding to 118 kg/cm 2 (=118/1.02 = 116 bar) (drum pressure) is 322 °C.  (ii) Degree of super heat = Superheated steam temperature – Saturated temperature   = 520 – 322 = 198 °C. (iii) Enthalpy of the superheated steam as found from steam table corresponding to 110 kg/cm 2 (=110/1.02 = 108 bar) and 520 °C is 815.8 kcal/kg. Problem (Gujarat BOE 2021, 5 marks0 Calculate the heat required to be added to 1000 kg of steam at 15 kg/cm 2 in order to superheat to 400 centigrade. Solution m steam = 1000 kg P steam = 15 kg/cm 2 Final temperature of superheated steam, T 2 = 400 0 C Saturation temperature of steam at 15 kg/cm 2...

An Air Sample taken from old waterlogged workings showed the following composition. CO 2 -3.0 percent, O 2 - 16.2 percent, N 2 - 79.5 percent, CH 4 - 1.3 percent. (The composition of normal air by volume is O 2 - 20.93 percent, N 2 - 79.04 percent & CO 2 - 0.03 percent). Find the Black damp content of the sample. (DGMS FCMC 2021)

135 ton of coal is to be hauled by direct rope haulage in a shift of 6 hours hauling time where the length of haul is 1100 m. The average speed of rope is 6 km/hr. Set changing time is 1 min & tub capacity is 1.5 ton. Calculate the number of tubs per set?

A 20 m chain was found to be 10 cm too long after chaining a distance of 2000 m. It was found to be 18 cm too long at the end of the day’s work after chaining a total distance of 4000 m. What is the true distance if the chain was correct before the commencement of the day’s work?

Number System

Measurements Fundamentals (Errors and Standards)

Design the 5 sections of a 6-stud starter for a 3-phase slip-ring induction motor The full-load slip is 2% and the maximum starting current is limited to twice the full-load current. Rotor resistance per phase is 0.03 Ω. (AMIE Winter 2023)