What is CGD.pptx

all about cgd

1. What is CGD ? City Gas Distribution “City or local natural gas distribution network” means an interconnected network of gas pipelines and the associated equipment used for transporting natural gas from a bulk supply high pressure transmission main to the medium pressure distribution grid and subsequently to the service pipes supplying natural gas to domestic, industrial or commercial premises and CNG stations situated in a specified geographical area;

2. Meter Meter

3. CGD Network authorization Under the Petroleum and Natural Gas Regulatory Board (PNGRB) Act 2006, PNGRB grants the authorization to the entities for developing a City Gas Distribution (CGD) network (including PNG network) in a specified Geographical Area (GA) of the country.

4. What is T4S ? T4S Means Technical Standards and Specifications including Safety Standards for City or Local Natural Gas Distribution Networks & Natural Gas pipelines.

5. City gate station (CGS) The point where custody transfer of natural gas from natural gas pipeline to the CGD network takes place and this may also be referred to as City Gate Measuring and Pressure Regulating Station.

6. Critical infrastructure / activity/ processes Pressure reduction skid CGS (active /monitor combination) with a minimum 50% redundancy including slam shut valve for over pressure protection and creep relief valves . On line odorisation equipment. Height of the vent shall be minimum 3 meters above working level. Gas detectors shall be installed at critical locations . HSSE Management System. Emergency Response Plan, Disaster Management Plan and written emergency procedures. Also, provide for an Emergency Control Room, manned round the clock and equipped with effective communication system and emergency vehicles fitted with communication facilities, first aid equipment, fire extinguishers, gas detectors, repair kits and tools, maps, plans, material safety data sheets etc.

7. Main Functions Isolation Filtration Pressure reduction. Metering. Pre Heaters PSV & CRV. Odorization .

8. Main Functions Isolation

9. Filtration Filtration

10. Pressure reduction.

11. Metering. Metering.

12. Pre Heaters Pre Heaters

13. Odorisation The odorization process of distributed gases is required for safety reasons and it acts as a “warning agent” in case of leakage. The process consists of injecting a chemical agent — an odorant — that adds a smell to the gas, turning it easily recognisable . For PNG 10 PPM (Part per million) 20 milligrams of methyl mercaptan per cubic meter (mg/m³ ) For LPG 25 parts per million (ppm)

14. Valve chain

15. primary network pressure above 100 psig (7 bar) and below 711 psig (49 bar )

16. secondary network a pressure below 100 psig (7 bar) and above 1.5 psig (100 mbar ) Also called called low-Pressure Distribution

17. tertiary network CGD network that operates at pressure less than 1.5 psig (100 mbar)

18. sub-transmission pipeline means a high pressure pipeline connecting the main transmission pipeline to the city gate station but is owned by the CGD entity ;

19. velocity in the pipeline network The Maximum velocity in the pipeline network should be limited to 100 ft /sec (30 m/sec ) Immediately after pressure regulating instrument.

20. type of Pipe line Steel Pipeline. ( 4” , 8” , 12”……) Mdpe Pipe Line ( Medium density Polyethlen Pipe. Size ( 20 mm, 32 mm, 63 mm, 90 mm, 110 mm , 125 mm , 180 mm.

21. MDPE Medium-density polyethylene ( MDPE ) is a type of P olyethylene defined by a density range of (0.926 - 0.940) gm/cm3 Code of MDPE Pipe- IS 14885 . IS 14885 (2001): Polyethylene Pipes for the Supply of Gaseous Fuels Colours – yellow – PE 80 grade Orang – PE 100 grade # PE100 is a higher density material than PE80 # Material Designation Minimum Required Strength (MRS)MPa PE100 10.0 PE80 8.0

22. Fittings of MDPE FITTINGS OF MDPE- Saddle 2. Coupler 3. Elbow 4. Tee 5. End cap 6. Reducer

23. TOOLS & TACKLES- TOOLS & TACKLES- 1- MDPE PIPE CUTTER 2- UNIVERSAL STRAP WRENCH 3- REROUNDING TOOL

24. TOOLS & TACKLES- 4- SCREAPER 5- ALIGNEMENT CLAMP. 6- MANHOLE COVER LIFT KEY 7- ELECTRO FUSION MACHINE

25. DRS/FRS Inlet pressure - 19-26 bar. Outlet pressure – Below 7 bar. DRS stand for high flow Capacity for a whole district.

26. DRS/FRS Flow Chart 19-26 Bar Below 7 bar

27. Service Regulator (SR) Inlet pressure – 4 bar (4000 Mbar) Outlet pressure – 100 Mbar Capacity – 100 scmh , 150 scmh … ets To connect lage no of customer as per sr Capacity.

28. Regulator Inlet pressure – 4 bar Outlet pressure – 21 mbar Flow capacity – 6.5 scmh Only connect 10 – 12 Customer.

29. Meter Regulator Inlet pressure – 100 mbar Outlet pressure – 21 mbar Flow capacity – 2.5 scmh

30. Meter Inlet pressure – 21 mbar Outlet pressure – 21 mbar P max – 0.5 bar Rating – G 1.6 Min flow- 0.016 m3/h Max flow – 2.5 m3/h Type – Diaphragm. Flow capacity -2.5 m3/H Capacity in – 1.2 Liter.

31. Pressure Gauge Pressure. When pressure is measured relative to atmospheric pressure (14.7 psi), it is called gauge pressure (psig). The term gauge pressure is applied when the pressure in the system is greater than the local atmospheric pressure Absolute pressure When pressure is measured relative to a perfect vacuum, it is called absolute pressure

32. Pressure

33. Domestic gas pressure Pressure in domestic gas pipeline 1.01325 + .21 = 1.22325 bar 1223 mbar

34. Type of Gas Meter Diaphragm. RPD (rotatory positive displacement ) (above 0.5 bar Pressure) Turbine meter. ( above 20 bar Pressure) Orifice meter Ultrasonic flow meters. Coriolis meter

35. Meter selection G -1.6 (min 0.016 max 2.5) M3/h G-2.5 (min 0.025 max 4 ) m3h G- 4 (min 0.04 max 6 ) m3/h G-6 (min 0.06 max 10) m3/h G-10 (min 0.10 max 16) m3/h G-16(min 0.16 max 25) m3/h G-25 (min 0.25 max 40) m3/h

36. Meter selection Total Consumption – 250 scmh Consumption in m3/h = Consumption/ correction factor = 250/2.936 Consumption – 85.14 m3/h G – 65 (min 0.65 max 100)

37. What is scm ? Standard Cubic Meter  means the quantity of Gas that occupies a volume of one (1) cubic meter at a temperature of 15oC (fifteen degrees Celsius) under an absolute pressure of 1.01325 Bar.

38. ~~~~ THANK YOU ~~~~