Medical gas supply.pipelines and cylinders

pipe lines and cylinder for medical gas supply

1. MEDICAL GAS SUPLY:
CYLINDERS & PIPELINE
PRESENTED BY :DR. SAURAV

2. COMPONENT OF MEDICAL
GAS CYLINDRES
BODY
 constructed of steel ,
 alloys added for strength.
Aluminum cylinders are MRI compatible
VALVE
 filled and discharged through a valve
attached to the neck,
 made of bronze or brass

3. Different cylinder valve

5. Packed valve :
stem is sealed by resilient packing such as Teflon ,
Diaphragm valve :
a diaphragm separated the stem from the seat.
. Advantages:
# can be used fully using a one half to three quarters
turn
# less likely to leak
# No stem leakage

8. PORT
 the point to exit for the gas.
STEM
 closes the valve by sealing against the seat.
When the valve is opened, the stem moves
upward, allowing the gas to flow to the port

9. PRESSURE RELIEF DEVICES
acts when excessive pressure is build up.
types :
Rupture disc,
 Fusible plug
combination of both

10. PRESSURE RELIEF VALVE
recluse or prevent
discharge of the
cylinder contents after
normal pressure have
been restored.

11. CONICAL
DEPRESSION
 receives the retaining
screw of the yoke.

12. NONINTERCHANGEBLE
SAFTEY SYSTEMS
PIN INDEX SAFTEY
SYSTEM

13. PIN INDEX SYSTEM
OXYGEN 2,5
NITROUS OXIDE 3,5
CYCLOPROPANE 3,6
AIR 1,5
NITROGEN 1,4
NITROUS+OXYGEN 7

14. Valve outlet connection for
large cylinders

15. SIZE OF CYLINDERS
Cylinder classified using a letter code
A type cylinders are smallest
SIZE E is the cylinder most commonly used

16. TYPICAL MEDICAL GAS
CYLINDRES, VOLUMES, WEIGHT
cylind
er size
dimen
sion
weight
(ib)
Air CO2 oxyge
n
Nitrou
s
oxide
B 3 1/2
x 13
5 370 200
D 4 1/2
x 17
11 375 940 400 940
E 41/4 x
26
14 625 1590 660 1590
M 7 x
43
63 2850 7570 3450 7570
G 8 1/2 x
51
97 5050 12300 13800

17. CONTENTS AND PRESSURE

18. CONTENT AND PRESURE

19. TESTING
Tensile test
Strips are cut longitudinally from the cylinder and stretched until
they elongated The yield point should not be less than15 tons
per square inch
Flattening test
One cylinder is kept between two compression blocks and then
oressure is applied to flatten it til distance of becomes six times
the thickness of walls.
Impact test
Three longitudinal and three transverse strips from a finished
cylinder are taken and struck by a mechanical hammer .The
mean energy needed to produce a crack should not be less than
5 feet lb for tranverse strip and 10 ft lb for longitudinal strip

20. Bend test
A ring of 25 mm width is cut from that cylinder and
equally divided into four strips.each strip is than bent
inward until the inner edge are apart not greater
than the diameter of the strip. The approved cylinder
should not develop any crack
Hydraulic test or pressure test
The test is usually done by the water jacket method.
here the proof pressure applied inside is
236.2kgf/cm this test also determines wether it is
leak proof or not

21. FILLING
DOT,s regulation limiting the amount of a gas cylinder
may contain
The pressure in a filled cylinder at 21.c may not
exceed the service pressure marked
The pressure in the cylinder at 55.c may not exceed
1.25 times the maximum permitted filling pressure at
21.c
In case of liquefied gas , the maximum amount of
gas allowed to be filled is defined by filling density .
The filling density is the percent ratio of the weight
of gas in cylinder to the weight of water the cylinder
would hold at 16.c

22. COLOR OF CYLINDER
 GAS USA INTERNATION
AL
oxygen Green White
Carbon dioxideGray Gray
Nitrous oxideBlue Blue
helium Brown Brown
Nitrogen Black Black
air Yellow White & black

23. MARKING ON THE
CYLINDERS
DOT and TC regulation requires following
specific marking on cylinders :
DOT and TC specification number to indicate
the type of material used in manufacture of
the cylinder
Service pressure of the cylinder in pound per
square inch
Serial number and identifying symbol of the
purchaser , user or manufacturer

24. MARKING ON THE
CYLINDERS
The initial qualifying test date with an
identifying mark for the testing facility
Retest date and testing facility
A five pointed star stamped after the most
recent test date
A plus sign if cylinder can be charged up to
10% in excess of the marked service
pressure

25. RULES FOR SAFE USE OF
CYLINDERS
Cylinders should be handled only by trained person
Cylinder valves, regulator. Gauges, and fitting
should never come into contact of oils , greases ,
organic lubricants etc
Cylinders should not be subjected to extreme of
temperatures
Connection to piping , regulator, and other
equipments should always be kept tight to prevent
leakage

26. RULES FOR SAFE USE OF
CYLINDERS
No part of the cylinders should be tainted , painted
or modified by users
A cylinder should never come into contact of
electricity
Before use ,cylinder should be identified by the
label. The color of the cylinder should not be relied
upon for identification
Only DOT or ICC approved cylinder should be used
A pressure regulator should always be used

27. Before any fitting is applied to cylinder valve ,
the valve should be opened slowly and briefly
to remove dust or any other particle
( cracking)
A sealing washer or gasket in good condition
should always be used with small cylinder
valve . If more than one seal is used the pin
on yoke may not extrude far enough to
engage mating whole or safety pin index

28. ·A cylinder valve should be opened slowly
,because if gases passes quickly into the
space between valve and the yoke or the
regulator , the rapid recompression in this
space will generate large amount of heat
.because there is no space for dissipation of
heat , this constitutes an adiabatic process.
Particle of dust, grease, etc present in that
space may be ignited by the heat causing a
flash fire or explosion.

29. STORAGE
A definite area should be designed to store the
cylinders
The storage area should be clean , cool and made
of fire resistant materials with adequate ventilation
Cylinder containing flammable gases should not be
stored in an enclosure containing oxidizing gas
Combustible material should not be kept near
cylinder containing oxygen or nitrous
Small cylinders are best stored upright or
horizontally in bins or racks
There should be a system of inventory for both
empty and full cylinders

30. HAZARDS
incorrect cylinders
Incorrect content
Incorrect valve
Damaged Valve
Suffocation
Fires
Explosion
Contamination of cylinder content
Theft of nitrous oxide

31. MEDICAL GAS PIPELINE SYSTEMS

32. COMPONENT
A central supply
Piping extending to location where gas
supply is required
Terminal point

34. Manifolded cylinders

35. Source of gases
Oxygen
Gaseous supply( G or H type )
Liquid supply ( when large amount of oxygen
is required , it is less expensive and more
convenient to store )
Oxygen concentrator
Nitrous oxide
Large cylinder manifold

36. Medical air
Definition : It is defined by NFPA as ,
regardless its sources, has no detectable
liquid hydrocarbon, less than 25 ppm
gaseous hydrocarbon , less than 5mg/m3 of
particulates of 1 micron size or greater at
normal atmospheric pressure and a dew
point of less than 4° c

37. Manifolded cylinders with a proportioning
device which mixes gases from oxygen and
nitrogen cylinders
Motor driven air compressor
Carbon dioxide
High pressure cylinder

38. PIPED DISTRIBUTION SYSTEM
Main lines pipe connecting the source to riser
or branches lines or both
Risers vertical pipe line connecting the main
lines with branch lines at various levels
Branch line that service a room or rooms
Pipes are made of copper
Oxygen pipe lines have ½ inch outer
diameter and that of other gases is 3/8 inch
diameter

39. TERMINAL UNITS
COMPONENTS
Base block
This the part of the terminal unit that attached
to the pipeline distribution system
Primary valve( automatic shut off valve, self
sealing device, primary check valve)
 opens and allows gas to flow when male
probe is inserted and closes automatically
when the connection is broken

40. Secondary valve
( shut off valve, maintenance valve)
is designed to shut off when primary valve is
removed for cleaning or servicing

41. GAS SPECIFIC CONNECTION
POINT( SOCKET ASSEMBLY)
two types ---
Threaded DIAMETER INDEX SAFTEY
SYSTEM
PROPRIETARY QUICK CONNECTOR

42. DIAMETER INDEX SAFETY
SYSTEM

43. QUICK CONNECTOR
Allows apparatuses to be connected or
disconnected by a single action
Each quick connector consist of a pair of gas
specific male and female part
A releasable spring mechanism locks the
components together

44. Hoses
connection between terminal units and the
ventilator or anaesthesia machine
 color coded and have the name and
chemical symbol of the gas

45. Types of terminal unit
Wall mounted
Ceiling mounted

46. Wall mounted terminal unit

47. Testing of medical gas
distributing system
Initial test
Blow down test
After the pipelines have been installed , but before
the installation of terminal units, the line must be
blown clear using oil free dry nitrogen
Initial pressure test
Each section of piping system must be subjected to
1.5 times of working pressure ( minimum1034 kpa)
with oil free nitrogen with source valve closed. It is
maintained and each join has been checked for
leakage

48. standing pressure test
after all the component of the system have been installed , the
entire system is subjected to 24 hours standing pressure at 20%
above the normal operating line pressure
piping purge test
to remove particulate matter , intermittent purging is done in
every outlet ,until no discoloration on a white cloth held over the
outlet
test for cross connection
to ensure that gas delivered at each terminal is that shown on
the outlet label. One gas system is tested at a time

49. out flow test
 to ensure that oxygen , nitrogen, and air
outlet deliver 100L/min without a pressure
drop of no more than 35 kpa at a static
pressure of 345kpa
alarm test
piping purity test

50. Operational pressure test
Piping system for gases other than nitrogen
must maintain the pressure at 345kpa ±35
.piping system of nitrogen must maintain a
pressure at 1100 kpa
Medical air purity test
Air source must be analyzed for dew point,
carbon monoxide, gaseous hydrocarbon etc

51. PROBLEMS WITH THE PIPING
SYSTEM
Inadequate pressure
Causes: damage of any part, compressor
failure, leaks, closure off shut off valve ,
obstruction, kinking of hose etc
Leaks
May hazardous if oxidizing gases are
allowed accumulate in a closed room

52. High pressure
Causes, most commonly failure of regulator,
ice formation
Alarm problems
Failure, absence or disconnection
False alarm.

53. Contamination of gases
can be serious problem when a new pipeline
is opened