RRB JE Mechanical case studies
RRB JE Mechanical · Put your knowledge to work in context.
RRB JE (Mechanical) is the competitive recruitment examination through which the Railway Recruitment Boards fill Junior Engineer and closely related technical posts in Indian Railways, including mechanical-department vacancies in workshops, diesel sheds, carriage-and-wagon depots and production units. Candidates normally need a diploma or degree in mechanical engineering, so the paper assumes a working knowledge of the standard diploma syllabus rather than school-level science alone. The RRB JE Mechanical case studies are 5 cases and about 3,731 words.
1Two press lines, one deadline: costing the cheapest production plan
Phoenix Fabrication has won a contract for 1,200 acceptable MS brackets, to be delivered within three working days of eight hours each, giving 24 machine-hours per press line. The shop has two lines.
767 words, about 4 min2Eight workstations, six conditions: testing which constraint earns its place
Eight probationary Junior Engineers - A, B, C, D, E, F, G and H - are to be allotted eight numbered workstations in a single row on the shop floor, numbered 1 to 8 from left to right as seen by the supervisor, all facing the supervisor's desk. The placement plan must satisfy six conditions: (i) A is at the left end; (ii) exactly two persons are placed between A and G; (iii) E is immediately to the right of C and immediately to the left of G; (iv) B is second to the left of D; (v) H is immediately to the right of B; (vi) F is at the right end.
860 words, about 4 min3Cooling tower short of duty: heat balance, cycles of concentration and a pitting problem
At a textile processing unit, a cooling tower rejects heat from a process exchanger. Circulating water flows at 5 m³/h (density 1,000 kg/m³, specific heat 4.18 kJ/kg·K) and leaves the exchanger 8 °C warmer than it enters.
716 words, about 4 min4A /29 that cannot hold eight devices, and a register that loses its part codes
A fabrication unit is networking its shop floor. The existing LAN is numbered 192.168.10.0/29.
698 words, about 3 min5Suction lift versus NPSH: deciding what to change before commissioning
At a water treatment plant, a centrifugal pump draws clarified water from an open sump whose surface is 2.5 m below the pump centreline, and delivers 90 m³/h. The suction line is 150 mm NB, 9 m long, with two 90° bends, a foot valve and a strainer; at design flow the friction loss in it is calculated as 1.2 m of water column.
690 words, about 3 min