1. WELCOME TO SHARING SESSION - 3

2. I NDIAN INTRODUCTION TO IBR R EGULATION B OILER 1950

3. IBR is Indian Boiler Regulations, which was created in 15 th September 1950 in exercise of the powers conferred by section 28 & 29 of the Indian Boilers Act. The Indian Boilers Act was formed in 1923, 23 rd February to consolidate and amend the law relating to steam boilers. What Is IBR?

4. Which steam boilers are regulated by IBR ? Steam boiler: Steam boilers under IBR means any closed vessel exceeding 25 liters in capacity and 1 Kg/cm2 design or working gauge pressure or temperature is more than 100 Deg C which is used expressively for generating steam under pressure and includes any mounting or other fitting attached to such vessel which is wholly or partly under pressure when the steam is shut off. ?

5. Which steam pipes are regulated by IBR ? Steam pipes: IBR steam pipe means any pipe through which steam passes from a boiler to a prime mover or other user or both if pressure at which steam passes through such pipes exceeds 3.5 kg/cm2 above atmospheric pressure or such pipe exceeds 254 mm in internal diameter and the pressure of steam exceeds 1 Kg/cm2 above atmospheric perssure includes in either case any connected fitting of a steam pipe. :

6. Heat Treatment / Stress relieving Condition :- 1.If Thickness More than 19mm OR 2. If Carbon more than 0.25% :

7. Heat Treatment / Stress relieving  Where the welded joints connects parts that are of different thickness then the governing thickness as follows :-  The Thinning of two adjacent butt welded componnt including shell to end connection.  The thickness of the shell in connections to flat ends.  The thickness of the shell/end in nozzle attachment welds.  The thickness of the nozzle at the joint in nozzle to flange connection.  The thickness of the pressure part at the point of attachment, where a non pressure part is welded to a pressure part. :

8. Heat Treatment / Stress relieving  Requirement for Heat Treatment:-  Furnace Size will be adequate  It shall be so designed as to prevent direct implingement of flame on the drum.  The temperature of the furnace at the time of the drum placed in the furnace shall not be higher than 300 deg C  For carbon steel a stress relieving heat treatment shall be performed by heating part to at least 600 +/- 20 deg C.  As per characteristic of material different temperature may be used. :

9. Heat Treatment / Stress relieving  The part to be stress relieved shall be bought slowly up to specified temperature & held at that temperature for a period proportioned on basis of at least 2 ½ min per mm (Apprx 1 hr/25mm of thk) & shall be cooled in the furnace  After withdrawal from furnace the part shall be allowed to cool in still atm. :

10. Hydraulic Test  Test Pressure = 1.5 x Design Pressure  Hydraulic test to be carried out after completion of manufacturing & alternatively test may be made on copletion of erection at site. :

11. IBR Regulation  Reg 215:Ligament Efficiency Calculation  Reg 270:Drum Shell Thickness Calculation  Reg 271:Allowable Stress Calculation  Reg 279:Compensation Calculation  Reg 338:Tube thickness Calculation  Reg 350:Pipe Thickness Calculation  Reg 362:Branch Calculation  Reg 278:Dished end Thickness Calculation  Reg 277:Dished End With Opening  Reg 579:Manhole Rim thickness calculation  Reg 281:Requisite Mountings, Fittings and Auxiliaries  Reg 342:Header End Cover Thickness Calculation :

12. Requisite Mountings, Fittings and Auxiliaries Every boiler shall be provided at least with the following:-  Two safety valves, In no case should the bore of the seat of the valve be less than 19 mm (¾")  Two means of indicating water level  A steam pressure gauge  A steam stop valve  A feed check valve  A blow –down cock or valve  A manhole, Handhole  Vent Valve

13. Requisite Mountings, Fittings and Auxiliaries  Fusible plugs as provided under Regulation 331  In the case of boilers fitted with integral superheaters, an additional safety valve shall be fitted at the end of the superheater outlet header  One feed apparatus. When the heating surface exceeds 200 square feet-two independent feed apparatus, each such apparatus shall have a capacity of not less than the maximum continuous rating of the boiler.  In the case of Marine Type boilers low water alarm may be fitted in place of a fusible plug.

14. Requisite Mountings, Fittings and Auxiliaries  In the case of automatic or semi-automatic oil-fired or gas fired boilers, low water alarms may be fitted in preference to fusible plugs provided such boilers are equipped with automatic tripping device to disconnect fuel supply and to start the feed pump simultaneously in the event of low water in the boilers..

15. Automatic firing controls Automatic firing controls shall comply with the following requirements:- At all times they shall control effectively the supply of fuel and air to the combustion equipment. Flame failure or pilot flame failure Failure to ignite the fuel at the burner within a pre- determined time. When the water level in a boiler with a perceptible water level falls below a pre-determined safe level. The control shall also cause an audible alarm to sound..

16. Automatic firing controls Failure of forced or induced draught fans or any automatic flue damper. Increase in furnace pressure to a predetermined value.

17. Pressure Gauge a) For pressure up to and including 35 kg/cm2, pressure gauge dial shall be graduated in kg/cm2 from zero to twice the pressure as nearly as may be practicable. b) For pressure exceeding 35 kg/cm2 the range of the graduation shall be from zero to one and a half times the maximum permissible working pressure, as nearly as may be practicable, but in no case shall the maximum graduation on the gauge be less than 70 kg/cm2 c) The scale on the dial shall be clearly and permanent marked in kg/cm2. d) The dial of each pressure gauge shall have to be marked upon it in red, the maximum permissible working pressure. e) Where the gauge is compensated for a head of water between the gauge and the boiler connection, the amount of such compensation shall be marked on the dial. Pressure gauge shall be calibrated within an accuracy of ± 1%. Boiler pressure gauges shall not be less than 150 mm in diameter. f) The travel of the pointer of the dial gauge shall not exceed 325o C. ?

18. Water Gauge Every boiler shall have two means of indicating the water in it of which one shall be conventional gauge glass: Provided that in the case of boiler drums below 3 feet (91 cm) diameter where there is difficulty in fitting two water gauges, two test cocks and a glass water gauge shall be fitted. b)The lowest visible part of the glass of the water gauge and lower test cock shall be fixed at safe working level. For locomotive type and vertical boilers this shall not be less than 50 millimeters above the highest part of the firebox roof plate. c) Minimum length of the visible portion of the gauge glasses shall be 200 mm. The length may be increased depending upon the capacity of the boiler by the Chief Inspector/Director of boiler of the manufacturing State. d)Glass water gauges shall be so placed as to be easily seen and reached by the boiler attendant. The fittings of glass water gauges and test cocks shall be of substantial make with large passage ways through them to facilitate cleaning. The gauge cocks when open shall have their handles in a vertical direction and each handle at its junction with the plug shall be plainly marked with a deep line to indicate the direction of the passage way through the plug. When detachable handle are provided arrangement shall be made to prevent incorrect fitting of the handles. ?

19. Boiler Blow Down Water contains certain percentage of dissolved solids. The percentage of impurities found in boiler water depends on the untreated feed water quality, the treatment process used and the boiler operating procedures. As a general rule, the higher the boiler operating pressure, the greater will be the sensitivity to impurities. As the feed water materials evaporate into steam, dissolved solids concentrate in the boiler either in a dissolved or suspended state. Above a certain level of concentration, these solids encourage foaming and cause carryover of water into the steam. This leads to scale formation inside the boiler, resulting in localised overheating and ending finally in tube failure. It is therefore necessary to control the level of concentration of the solids and this is achieved by the process of 'blowing down', where a certain volume of water is blown off and is automatically replaced by feed water - thus maintaining the optimum level of total dissolved solids (TDS) in the water. Blow down is necessary to protect the surfaces of the heat exchanger in the boiler. ?

20. Boiler Blow Down RECOMMENDED TDS LEVELS FOR VARIOUS BOILERS Boiler Type Maximum TDS (ppm)* 1. Smoke and water tube boilers (12 kg/cm2): 5,000 ppm 2. Low pressure Water tube boiler: 2000–3000 3. High Pressure Water tube boiler with superheater etc. :3,000–3,500 ppm 4. Package and economic boilers :3,000 ppm 5. Coil boilers and steam generators: 2000 (in the feed water) ?

21. Thank You ?