This document discusses PT IEV Gas's delivery of clean natural gas energy. It describes the tube skid unit that transports compressed natural gas cylinders in compliance with safety standards. Safety devices are installed on equipment like the tube skid, pressure regulator unit, and heaters to prevent overpressurization and other hazards. The properties of natural gas are discussed, including its odorless and flammable nature. Risk assessments and safety protocols are recommended to ensure its safe delivery to customers.

1. Delivering Clean Energy to Your Doorstep
PT IEV Gas - 2014
Prepared by Danu Jaya

3.  Tube Skid Unit
The manufacturing of the
CNG tubes are in compliance
to:
►US DOT 49 CFR § 178.37 “Specification
3AA and 3AAX seamless steel cylinders”
►ISO 11120 – Gas Cylinders – Refillable
seamless steel tubes for compressed gas
transport, of water capacity between 150l
and 3000l – Design, Construction and
Testing

4. CNG VEHICLE
PRU
(PRESSURE
REGULATOR UNIT)
CUSTOMER

5. Natural gas properties – Ignition and fire
 Gas released in the open space will quickly
disperse harmlessly
 Gas in a confined space, if ignited, will create
a localized high pressure
 Confined areas are pits, ceiling or roof
pockets.
 The gas/air concentration range for
flammability is narrow at low pressure (5 to
15% by volume)

6. Properties of Natural Gas
1971
1 0

7. Properties of Natural Gas
Odorless – Colorless -
Tasteless
Methyl Mercaptan is added to give it it’s
distinguishable “rotten egg” odor
Odorized natural gas is detectable at
concentrations significantly less than 1%

8. Properties of Natural Gas
Non-Toxic
75~95% - methane
Often listed as a “Hazardous Material”
due to it’s flammability, not it’s toxicity
Only through it’s ability to displace
oxygen can it pose an asphyxiation
hazard

9. 9
Properties of Natural Gas

10. Natural Gas
0.6
10
Properties of Natural Gas
Vapor Density
30% lighter than air
Will rise to sky, or collect near the
ceiling
Air = 1
Propane
1. 56

11. Properties of Natural Gas
Flammable
Limits
Too Rich
15%
5%
Too Lean

12. Properties of Natural Gas
Heating Value
1,000 BTU per cubic foot

13. Properties of Natural Gas
Combustion Products
Complete combustion = heat, carbon dioxide &
water vapor
Incomplete combustion = carbon monoxide

14. 14
Properties of Natural Gas
Auto Ignition
Temperature
Natural Gas :1163º F / 628 º C
Propane : 957º F / 514º C
Gasoline : 632º F / 333º C

15. Safety Devices installed on equipment that
placed on customer site (DS)
◦ Tube Skid Safety Devices
◦ PRU Safety Devices
◦ Heater Safety Devices

16.  Rupture Disc
◦ A rupture disc, also
known as a bursting
disc or burst
diaphragm, is a non-reclosing
pressure
relief device that, in
most uses, protects a
pressure vessel,
equipment or system
from over
pressurization or
potentially damaging
vacuum conditions

17.  PRU installed with several safety devices,
mechanical protection and static electrical
protection. Those devices are:
◦ PSV
◦ ESD System
◦ Earth System
◦ Electrostatic discharge system
◦ Hose Restrain System

18.  Pressure Safety Valve
◦ is a valve mechanism
which automatically
releases a substance
from a boiler, pressure
vessel, or other system,
when the pressure or
temperature exceeds
preset limits

19.  The CNG PRU packages are
provided with an Emergency
Shut Down System Device.
 The ESD system is activated
when pressure exceeding
preset pressure
 The ESD system, when
activated,
◦ Brings the unit to an
immediate halt.
◦ Isolates the unit from Gas
Suction Line.
◦ Closes all the output priority
valves, thus isolating the
Compressor, Cascades &
Dispensers from each other.

20.  The filling Hoses of CNG
Dispensers are Electrically
Conductive & designed as
per ANSI / NGV 4.2
 Static charge is carried to
dispenser body, and does
not produce spark during
engagement and
disengagement of Filling
nozzle with Vehicle
receptacle.
 The dispensers are Earthed
to dissipate the Static
Charge, and leakage
current if any.
Anti Static Cable
(earthing)

21.  To prevent hose accidentally disengage in
hazardous movement, hose restrain system
installed during hose connection process
before opening TS valve.
 Restrain system can hold 2000 Kgs force

22.  Water Heater Installed to
prevent gas pipe in PRU to
became freezing due to gas
flow.
 Working temperature set on
maximum 80oC
 Temperature Control Device
Installed to prevent the
system overheating.

24. DoRisk Assessments prior to work
DoSafety Awareness to Team work
Doinspection of Safe Condition
Doproper PPE according to risk
Dofollow safety instruction

25. Don’t make any naked fire
Don’t ignore small case, big thing
came up from small
Don’t do if you’re don’t know

26.  July, 2014
 PT IEV Gas