Technical Presentation of Dispenser, Compressor, Cascade, Cylinder manufacturing & Mass flow meter. Hydrogen Blending in Natural Gas pipeline of CGD Network

1. CNG machines in details &
Hydrogen Blending Skid
Prepared by Rishabh Sirvaiya
Jai Shri Mahakaal

2. Topics
1. CNG Dispenser
2. Mass Flow Meter
3. Cascade
4. CNG Cylinder Manufacturing & Testing. IS
7285 Part 2
5. Compressor working & Priority panel logic.
6. Hydrogen Blending skid

3. CNG Dispenser

4. Schematic Diagram TGT

6. Schematic Diagram Compac

7. Dispenser Operational Philosophy
• The low bank valve will open and the filling is started.
• As soon as the min. flow rate 0.1 kg/min. is reached
the medium bank valve will open.
• As the min. flow rate is reached the medium bank
valve will close and high bank valve will open, till the
flow is stop with the monitoring of pressure by
pressure transducer.
• The pressure transducer will monitor the pressure in
vehicle, by 0 to 5 volt signal. This signal is
proportional to the pressure.

8. Dispenser internal tubing's &
instruments
Actuator
NRV
Filter
MFM

9. PG, PT, SRV & Bleed valve
PG
Bleed
valve
PT
PRV
Emergency
ball valve

10. Maintenance procedure of dispenser
• Close the isolation ball valve installed at low
medium and high bank.
• Vent the complete dispenser gas through bleed
valve.
• Make sure the three way filling ball valve is in
close position.
• Cut off the power supply.
• Leakages in the tube is due to the expansion and
contraction of tubing and fitting. Check the
leakages by soap solution, and perform the any
maintenance operation required.

11. How to read the display
First two digit
shows the Rs
after decimal &
the last two digit
shows KG after
decimal.
Totalizer reading
in KG or the sale
till date
Total Rs. Sale
till date
Emergency switch Stop Start
button

12. Mass flow Meter
TGT dispenser :- CNG 50 series K 80 series in Compac dispenser

13. MFM working logic
• The measuring principle is based on the controlled generation of coriolis force.
These forces always occur in a system where translation (linea) and rotational
movements are superimposed simultaneously
Fc = Coriolis force
m= moving mass
= angular velocity
V = tangential velocity
In mass flow meter sensor uses oscillation instead of rotational/angular velocity.

14. Mass flow rate
• Coriolis flow meter working principle is based on the Coriolis Effect. In nutshell,
the Coriolis force is one of the forces of inertia that affect tube oscillations. When
a substance, such as a liquid, begins to move through the pipes, the tube
experiences additional distortions in frequency due to the inertia of the flow. It
happens because the flow interacts with pipe walls. Due to the appearance of
additional effects on the walls, the inlet and outlet of the tube starts to vibrate in
different phases. Now their sinusoidal oscillations will have a difference in the
form of a small shift between them. Such a difference is called a shift phase. Mass
flow rate is determined by comparing and analyzing the time delay between two
sinusoidal phases. The higher shift phase, the higher flow rate.

15. Density
• Density is also measured by analyzing sine waves in
oscillations. When the flux density changes, the tube walls
oscillation frequency changes too.
• The greater the density of a substance in a stream, the lower
wall frequency of oscillations.

16. CNG Cascade

17. Cascade Schematic Diagram
NRV
Tee
Cross

18. 2 way ball valve Bleed valve
SRV

19. 3 way ball valve
Break away
coupling
2 way ball
valve
QRC
SRV
Pressure gauge
Bleed valve

20. Cascade working logic
• The cascade cylinders are separated by NGV
located b/w the low bank cylinders (20 nos.)
and medium bank cylinders (12 nos.), Medium
bank cylinders and High bank cylinders (8 nos.).
• The gas will always be filled in moving cascade
by the low pressure SS tube, because the NRV
allow the gas to transfer from low pressure
bank to Medium pressure bank and similarly
from medium pressure bank to high pressure
bank but not the vice-versa.

21. How to Connect the Cascade at Filling Station.
• Connect the Crocodile Clip of Earthling to the
Cascade & LCV.
• Connect the QRC of High pressure Hose to
High pressure bank of Cascade with the
vehicle key attached with the hose.
• Open the 3 way ball valve of station.
• Open the Isolation valve.

22. How to Dis-connect the Cascade at Dispensing
Station?
• Close the two way ball valve of High bank,
Medium bank & Low bank.
• Close the three way ball valve at the LCV point
and vent the gas of Connecting hose.
• Open the bleed valve of the cascade and vent
the gas b/w the QRC and the cascade 2 way
ball valve.
• Disconnect the Hose.
• Disconnect the Crocodile clamp.

23. CNG Cylinder Manufacturing & Testing
as per IS 7285 Part 2 (2017)
Cascade Capacity:-
• 3000 WL
• 4500 WL
• Note:- No welding is carried during the
manufacturing of CNG cylinder

24. Parameters
• Cylinder shell min. thickness 8.6 mm.
• Cylinder Concave base min. thickness 12.9 mm.
• Cylinder nominal dia. 267 ± 1 % mm.
• Cylinder length 1705 mm. (approx.)
• Water Capacity 75 +5% -0% WL.
• Hydraulic Pressure 425 bar.
• Test Pressure 255 bar.
• Manufacturing Process:- Hot spinning of
Seamless Steel tube. (Hot spinning for the base
joining and neck preparation)

25. For Seamless
Pipe

26. For New design (Type approval procedure) (Cl. 9)
• Test Carried out
– Hydraulic bursting test
– Pressure Cycling test
– Base check
– Mechanical testing
• Tensile test
• Impact test
• Bend test
After the Satisfactory Completion of above test
the Approval Certificate is issued.

27. For Batch Test Cl. 10 (200 Cylinders)
• Type Approval Certificate.
• Certificate from the manufacturer stating the cast
analysis of the steel.
• Evidence of heat treatment performed.
• Conformation that threads are checked properly.
• Certificate of Ultrasonic testing.
• Mechanical testing (tensile, impact & bend test).
• Hydraulic bursting test
• Hardness Test

28. Test on each cylinder Cl. 11
• Hydraulic Test
• Hardness Test
• Leakage Test
(Test medium air , Testing pressure at = 0.6*hydraulic pressure (255 bar), the pressure
should not decrease with time to confirm the leakage in cylinder)
• Capacity Check

29. Mechanical Testing (Cl. 10.1.3)
Tensile Test
The test piece from the cylinder is taken and test is carried out,
the elongation shall not be less than 14%.
Impact Test (Table 4)
Bend test
180 degree bending, No crack should be observed
S. No. Nominal Dia of cylinder greater
than 140 mm
Nominal Dia of cylinder greater than
140 mm
1 Transverse direction Longitudinal direction (Along the
cylinder axis)
2 Impact Strength 24-40 J/cm^2 Impact Strength 48-60 J/cm^2
3 Impact strength depends upon the
width and nos. of specimen tested.
Test temp. -20 degree Celsius
Depends upon the width and nos. of
specimen tested. Test temp. -20
degree Celsius

30. Pressure Cycling Test:-
The cylinder is hydraulically pressurised at the upper cyclic limit
(hydraulic pressure 425 bar) and lower cyclic pressure limit (10%
of hydraulic pressure, but greater than 30 bar).
Frequency of the cycle should not exceed the 15 cycles/min.
Total 12000 cycles pressurization and depressurization is carried
out.
After the test the cylinder base & shell thickness is checked. The
thickness should be greater than the min. design thickness.
Ultrasonic Testing
All Cylinder thickness, cracks and the pores are checked by
ultrasonic testing.

31. Hydraulic bursting Test:-
Pressurization is carried out in two stage.
(1) The pressure is increased @ not more than 5
bar/sec. upto the pressure value corresponding to
the initiation of plastic deformation.
(2) The pump discharge rate shall be maintained at a
constant rate until the cylinder burst.
Pressure/time curve is studied.
For satisfactory result P(yield) > 1.18*(P hydraulic)
& P(burst) > 2.25*(P hydraulic)
Note:- Complete description refer to cl. No. 10.5

32. Hardness Test:-
• Hardness test is carried out in accordance with IS 1500 (brinell) &
IS 1586 (Rockwell) or other equivalent method, to determine the
hardness within the specified limit by the cylinder manufacturer
depend upon the heat treatment used for the production.
Capacity check:-
• Manufacturer should check the water capacity of each cylinder
within tolerance limit.
Sr. No. Cylinder Capacity + tolerance in % - Tolerance in %
1 Upto 20 liters 10 0
2 Greater than 20 liters 5 0

33. Hydraulic Test
– Proof Pressure Test
The cylinder is pressurised till the hydraulic pressure and
hold for 30 sec. to check the leakage in cylinder if there is
pressure drop.
– Hydraulic Stretch Test
The cylinder is pressurised at the hydrostatic pressure and
hold for 30 sec. . The Total volumetric expansion is
measured due to the pressure applied.
Again the pressure is released and the volumetric
expansion is re-measured. Therefore the Permanent
expansion.
If the permanent / Total volumetric expansion is less than
equal to 10% the cylinder will be accepted otherwise the
cylinder will be rejected.

34. Compressor working &
Priority Panel logic

35. Compressor Operating Parameters
• Inlet Suction Pressure :16-19 kg/cm^2
• First stage pressure suction: 15 kg/cm^2
• Second Stage Pressure suction: 51.5 kg/cm^2
• Third Stage Pressure Suction: 137.5 kg/cm^2
• Discharge Pressure : 255 kg/cm^2
• Oil Pressure: 3.5 kg/cm^2
• 1st stage suction Temp. 30°C
• 1st stage discharge Temp. 133°C
• 2nd stage suction Temp. 50°C
• 2nd stage discharge Temp. 130°C
• 3rd stage suction Temp. 50°C
• 3rd stage discharge Temp. 105°C
• Gas Discharge Temp 50°C
• RPM 1500

37. Compressor Start logic
• As the compressor start button is pressed after clearing the faults displayed in the
PLC. (Initially the valve from the 2nd stage bottle/crank, 3rd stage bottle/crank,
Discharge filter drain valve are in open condition and connected to the BDV.
Therefore the pressure of all the stages is equivalent to BDV that’s within the range
of 20-25 kg/cm^2.)
If the pressure in the PT-102 (installed before the 1st stage of compressor) has the
pressure less than 16 kg/cm^2 Gas inlet Solenoid valve (SOV-107) will energize till
the gas flow stop or the pressure reached to the inlet pressure after PRV.
• Engine air starter valve (SOV-107) will energize to start the engine by air pressure.
Engine fuel shut off valve (SOV-106) (for the gas inlet to engine) will energize.
• When the engine attain the full speed of 1400 rpm, discharge filter drain valve
(SOV-105) will close after 5 sec. After 5 sec. time close 3rd stage suction drain valve
(SOV-104) and after 5 sec. time close 2nd stage suction drain valve (SOV-103). Now
the machine is running in loaded condition and gas will pass to priority panel.
Normal speed of engine should be 1500 rpm.

38. Compressor Stop logic
• If the pressure rises at the discharge of the 3rd stage compressor above 250
kg/cm^2 as sensed by PT-105 the main inlet valve (SOV 101) of gas entering to the
compressor will close.
• Then the SOV-103 ( from the suction separator drain valve of 2nd stage) will open,
SOV – 104 ( from the suction separator drain valve of 3rd stage) and SOV-105
discharge filter drain valve will open. So that all the pressurized gases from all the
stages will be depressurized and accumulated in the BDV.
• After unloading of compressor the engine fuel SOV-106 (gas fuel inlet valve to
engine) will close. And the engine will stop.
• If the compressor is running continuously for 90 minutes SOV 103 will open for 2
sec, SOV 104 will open for 2 sec and SOV 105 will open for 2 sec.
Drain valve SOV -102 suction separator cum blow down vessel will open and close for
5 sec. after every 24 hrs. to drain the oil and water.

40. Priority Panel logic
• First Priority:- SOV-201 (for the connection of high bank storage cascade to high bank Car
dispenser, Medium bank storage cascade to medium bank car dispenser & low bank storage
cascade to low bank car dispenser will always be energized ), to continue the flow when the
compressor is not running. Also the high pressure line of CNG dispenser is connected before
the PCV-200, so the high pressure bank will always get the high pressure irrespective of the
cascade pressure.
Mobile cascade SOV-208 will directly opened whenever selector switch provided at control panel
is “ON”, other wise it will open as per priority logic.
In case of emergency is pressed or flame detected all priority valves will be de-energized.
• Second Priority:-
When the pressure input PT-201 (Pressure transmitter before the inlet of priority panel) rises
above 200 kg/cm^2 for high bank storage cascade SOV-200 energies and open the actuated
valve PCV-200 for high bank storage cascade. SOV-200 will energies for 120 sec. If the
pressure remains below 200 kg/cm^2 then SOV-200 will de-energize and if the pressure will
be above 200 kg/cm^2 then SOV-200 will remain de-energize.
• Third Priority:-
When the pressure input PT-201 (Pressure transmitter before the inlet of priority panel) rises
above 215 kg/cm^2 for medium bank storage cascade SOV-202 energies and open the
actuated valve PCV-202 for medium bank storage cascade. SOV-202 will energies for 120 sec.
If the pressure remains below 215 kg/cm^2 then SOV-202 will de-energize and if the pressure
will be above 215 kg/cm^2 then SOV-202 will remain de-energize.

41. • Fourth Priority:-
When the pressure input PT-201 (Pressure transmitter before the inlet of priority
panel) rises above 230 kg/cm^2 for low bank storage cascade SOV-204 energies
and open the actuated valve PCV-204 for low bank storage cascade. SOV-204 will
energies for 120 sec. If the pressure remains below 230 kg/cm^2 then SOV-204
will de-energize and if the pressure will be above 230 kg/cm^2 then SOV-204 will
remain de-energize.
• Fifth Priority:-
When the pressure input (PT-201) rises above set point i.e. 240 kg/cm^2, (SOV 208)
energize and open actuated valve PCV-208 for mobile cascade. SOV -208 will be
energized for 120 sec. If after 120 sec. the pressure remains below 240 kg/cm^2
then SOV-208 will de-energize and if the pressure is above 240 kg/cm^2 then SOV
208 will remain energize.
Again the compressor will reach to the second priority and complete the repetion.
Whenever the later priority operate the earlier priorities will remain open.
In case during filling of medium bank cascade the high bank cascade pressure gets
lower downs the set pressure, the compressor will fill the high bank cascade after
the completion of 120 sec. period for medium bank

42. Hydrogen Blending in Natural Gas Pipeline
(Hydrogen Blending Skid) Pilot Project

43. Parameters
• Flow 100 m^3/hr
• Inlet 30 to 200 kg/cm^2 (g).
• Outlet: 21 kg/cm^2 (g)
• PCV-1 Set Pressure : 25 kg/cm^2 (g)
• PCV-2 Set Pressure : 21 kg/cm^2 (g)
% of H2 injection in Natural gas is 1-2 % by volume.
The hydrogen injection is limited to 2% because the CNG kits (M/s Eco Fuel system pvt
ltd. Limits the use of hydrogen % upto 2 % only.
Mobile Cascade assembly:-
• Total Nos. of cylinders mounted : 146 Nos.
• Per Cylinder Capacity:- 160 liters
• Manufacturer :- EKCK
• Working Pressure:- 200 kg/cm^2
• Manufacturing for the transportation for H2 Gas.
• Gas filled in a single cascade is 4230 m^3.

44. INSTRUMENTS USED
• PLC control actuator
– Make Sankey Controls STI4SIOAO
– -20 to 80 degree Celsius.
• PLC Control Valve
• Make Sankey Controls SS 304L/17-4 PH
• 2500 class
• Pressure control valve (PCV 1)
• Nirmal Industrial Control Pvt. Ltd.
• Inlet 25-33 kg/cm^2
• Set pressure 29 kg/cm^2
• Size ½”
• 300 class
• Slam Shut off valve
– Nirmal Industrial Control Pvt. Ltd.
– Set Pressure 29 kg/cm^2
– Size 1”
– Class 2500
• 1 st Stage Regulator / PCV
– Nirmal Industrial Control Pvt. Ltd.
– Inlet Pressure 60-200 kg/cm^2
– Set Pressure 25 kg/cm^2
– Size 1 “
– Class 2500

45. • 2nd Stage Regulator / PCV
– Nirmal Industrial Control Pvt. Ltd.
– Inlet Pressure 25-33 kg/cm^2
– Set Pressure 21.5 kg/cm^2
– Size 1 “
– Class 2500
• SRV 1 & SRV 2
• Secura Max
• SS 304L
• Size ½ “
• Class 2500
• BV
• GM Enginnering
• 1 “
• SS 304/304L
• Flow Control valve
• Make: KSB MIL Controls Ltd.
• Size 1 “
• Class 300

46. PT

48. Water Tank for venting of
Hydrogen gas
Nitrogen cylinder for the purging of
H2 in skid during maintenance an
flow rate control valve operation
Hydrogen Blending skid

50. Thank You
• Thanks to all my reporting authorities who
helped me to gain knowledge in CGD industry.
• Sorry (if you find any mistakes in the
presentation)
• Jai Shree Ram