Mine Management, Legislation & General Safety
1. What do you understand by the term “flame proof equipment”? Draw a list of instructions, responsibility for compliance and records that should be maintained to ensure that flame proof features remain effective.
2. A large mechanised opencast mine is being planned in a virgin area. Briefly slate and discuss the statutory notices that are to be sent and permissions/relaxations to be obtained. What steps should be taken to select, recruit and train the workmen, staff and officers?
3. Answer the following:
a. What should be the syllabus for pre-employment training for workers for an underground mine? What is the need for re-fresher training?
b. State the differences in statutory provisions relating to haulage and winding ropes?
4. Write short notes on the following:
a. Statutory provisions relating to working near mine boundaries, their rationale and adequacy.
b. Functions of Committee under Section 12 of the Mines Act.
c. Statutory provisions relating to supply and use of dust respirators.
d. Fly rocks in opencast mines, their causes and prevention.
5. (a) State and discuss statutory provisions relating to taking shelter while blasting in opencast mine. How would you ensure adequate shelter when there are private hutments and public road within the danger zone?
(b) In an underground mine, the Over man has reported probable explosion in a mechanised development district and 16 persons missing. Draw a list of actions, in order of priority that you would take to deal with the emergency and rescue/recover the missing persons.
6. What could be the occupational health problems with increasing mechanization? What steps should be taken to guard against the same.
7. Write short notes on the following:
a. Risk management
b. Effectiveness of Safety Committee
c. Statutory provisions relating to Rescue Rooms
d. Condition for use of trolley were locomotive below ground.
8. The management of a large opencast mine has entrusted the work of removal of overburden to a contractor. Deployment of contractor’s trucks and workers for removal of overburden has led to increase of accidents. Discuss the reasons for increase in accidents and suggest preventive measures.
Winning & Working
1. What are the suitable conditions for use of surface miner is opencast mine? What are the advantages and constraints of Surface Mining technology over shovel dumper working?
2. Write short notes on any four
(i) Operation of dragline in horizontal tandem
(ii) Stabilisation of water logged, unapproachable underground voids for protection of surface features.
(iii) Advantages and disadvantages of longwall advancing,
(iv) Inpit crushing system in opencast mine.
(v) Factors on which tub size depends in an existing underground mine.
3. Define capacity utilization in an opencast mine. Suggest the steps/ actions to be taken to improve the capacity utilization of a mine having capacity utilization of only 60%.
4. A large number of pillars at a shallow depth having active fire is proposed to be extracted by opencast method. Give in details the method of extraction, the type of equipment and manpower. Suggest special safety precautions that should be taken.
5. Write short notes on the following:
(i) Horizon mining
(ii) Management of hard roof in a longwall face
(iii) Sub-level caving
(iv) Underground-coal gasification
6. Write short notes on the following:
(i) Coking coal
(ii) Coal bed methane
(iii) Proved reserve
(iv) Regional exploration.
7. Describe the equipments needed, shaft support system and methodology to be adopted for sinking a shaft 6 m. dia. 300 m depth finished with lining. Strata consist of sandstone with two water bearing layers 12 metres each. Shaft is meant for cage winding.
8. In an underground mine it is proposed to depillar a panel with SDL for a production of 300 tonnes per day. Assume own conditions and give panel layout, no. and type of equipment and support plan.
Mine Ventilation, Explosion, Fires & Inundation
1. (a) What are the statutory provisions regarding inflammable gas and what are the latest method of determining the “Virgin gas content”?
(b) Explain the different statutory provisions/exemptions connected with fires while extracting developed pillars by opencast method. What precautions would you take to prevent spread of fire during such extraction?
2. (a) Discuss the following in detail:
(i) Controlled re-circulation
(ii) Peripheral Ventilation System.
(b) In a coking coal mine, spontaneous heating took place in the dip-most section. The mine is degree three gassy and is very extensive. What are the problems associated with such heating. What steps would you take to guard against such dangers?
3. (a) Explain with a sketch the design variables of an axial flow fan.
(b) The installed fan in a mine has-an efficiency of 63% and it requires 25 mm of w.g. to pass 8000m3/min. assuming the power cost to be Rs.4/- KWH calculate the annual cost?
4. (a) Explain:
(i) Use of CO2 in controlling spontaneous heating,
(ii) Alternatives to explosives.
(iii) Ventilation network analysis.
(b) Explain detail the ventilation requirements in a continuous miner district with a sketch of the ventilation circuit in the district. What are the sources of dust in the district and what measures are to be taken to prevent dust concentration in the district?
5. Write short notes on:
(i) Fire Resistant Hydraulic Fluid
(ii) Water Dam
(iii) Explosibility of coal dust
6. It is proposed to open a new underground mine having two seams A and B with the following mix of technology
(i) Manual mining-1 District -Top Seam “A” 4 M thick
(ii) Mechanisation with LHDs-2 Districts- Top Seam ‘A’4 M thick
(iii) Blasting Gallery method -1 District – Bottom Seam ‘B’ – 8 M thick
The minimum and maximum depth of the workings is lying in between 250 M to 400 M. Explain in detail the ventilation requirements, likely infrastructure, capacity of Main mechanical Ventilator and other provisions/establishments required. Assume your own conditions.
7. (a) Explain briefly:
(i) Water Danger Plan
(ii) Fan Drift
(b) A drift is ventilated by two lengths of ducting of 40 cm and 60 cm diameter respectively. What difference in quantity of air reaching the drift would result if the two ducting are replaced by a single 80 cm ducting of similar lining and construction?
8. What are the statutory provisions connected with dangers associated with water inrush from old workings? What details are to be shown in the plan according to the statute? Also describe the action plan when the water inrush assumes alarms levels. Assume your own conditions.
1. A 300 m deep bore hole is required to prove a coal! seam. Describe the drilling process and list out the equipments required.
2. Give short comprehensive note on the following technology along with main equipments, salient features, applicability and productivity to be given:
a. Surface miner
b. Continuous miner
3. Give main features of installation, safety and operation of main trunk belt conveyor required to evacuate 2000TPD in an incline mine of 3 km length having 1 in 8 gradient. Specifications and capacity to be given for belt conveyors.
4. List out the four main breakdown which commonly occur along with reasons for the following equipments:
a. 35T Dumper
b. 5 cum Rope shovel
c. Side Discharge Loader
d. Belt conveyor
Also suggest check list of maintenance for these equipment.
5. Describe a Load-Haul-Dumper. What are the suitable conditions for its application in an underground mine?
6. Describe briefly and give layout plan of a electrical substation of 5 million tonnes O.C. Safety features and energy conservation will be two main considerations for main sub-station layout. No. of equipment and load to be worked out for consideration of sub-station load. O.C. project has provision of 5 cum electric rope shovel and crushing plant.
7. What are the different types of man-riding systems used in underground mines? Discuss what conditions each will be applicable and why.
8. Write short notes on the following:
a. Use of fire resistant hydraulic fluid in belowground coal mine
b. Non-destructive testing (NDT)
c. Fluid coupling
d. Compressed air application in coal mines.
1. You are asked to make an estimate of the reserves of unworked coal in an underground mine having large leasehold area. The strata contains five seams of workable thickness at moderate depth. Two of the seams are being worked, the remaining seams being virgin. The strata are being intersected by a number of faults of varying and substantial displacements. There are extensive surface features like buildings, nallah, road, railway line etc. etc. State fully the successive steps which you would take up to ensure that the reserves will be calculated with reasonable accuracy.
2. Calculate the volume contained in cubic metres between three successive cross-sections of a trench cutting 50 metres apart. The width of the formation level is 6.6 metres, the side slopes are one vertical to two horizontal and the height at the top of the slopes in metre above formation levels are as follows:
3. What are the provisions of Coal Mines Regulations regarding;
(a) Type of plan to be maintained where a scam has an average inclination of more than 30 degrees from the horizontal.
(b) Details to be shown in the plan to be submitted with applications for permission for working under Railways and roads etc.
(c) Type of plans to be maintained when seams when are worked in a mine are lying within nine metres of each other.
(d) Plans to be submitted to the Chief Inspector when a mine is discontinued.
(e) Requirement of Surveyors.
4. The following lengths and bearings were recorded in running a traverse ABCDE, the length and bearing of EA having been omitted:
|Line||Length in metres||Bearing|
Calculate the length and bearing of the line EA.
5. Working of two adjoining mines have reached within 60 metres of common boundary. Describe how would you accurately carry out your survey which is required as per statue. The workings of one mine are accessible through an incline and a shaft while the workings of the other mine are accessible through shafts.
6. What method should be adopted to measure a large ground stock of coal exceeding 5 lakhs tones in one single heap with a maximum height of 20 m. Assume your own figures to illustrate the method of measure-ment. What are the necessary precautions to be adopted for correct measurement of such large quantity of coal stock?
7. A level driven in a coal seam dipping at 1 in 4 in direction S 10° W touches a down throw fault of 40 metres vertical displacement with a hade at 30°. Strike of fault is N 20°W. A drift driven from up throw side in direction of S 70°W at a gradient of 1 in 2 to touch the seam on the down throw side. Calculate the length of the drift.
8. In order to find out the distance between two inaccessible objects L and M across a river, a line AB 20 metres in length was ranged on this side of the river. As it was found that the object L could be seen from A but not from B and that the object M could be seen from B but not from A, the line AB was extended by 50 metres on each side from A to C and from B to D. The following angles were observed.
|LCA = 74°||MBD = 37°|
|CAL = 89°||BDM = 78°|
Calculate the distance LM.