Section
8 Plastic pipes
8.1 General
8.1.1 Proposals to use plastic pipes in shipboard piping systems will be
considered in relation to the properties of the materials, the operating conditions, the
intended service and location. Details are to be submitted for approval. Special
consideration will be given to any proposed service for plastic pipes not mentioned in
these Rules.
8.1.2 Plastic pipes and fittings will, in general, be accepted in Class III piping
systems. Proposals for the use of plastic in Class I and Class II piping systems will be
specially considered.
8.1.3 For Class I, Class II and any Class III piping systems for which there are
Rule requirements, the pipes are to be of a type which has been approved by LR.
8.1.5 The use of plastic pipes may be restricted by statutory requirements of the
National Authority of the country in which the vessel is to be registered.
8.2 Design and performance criteria
8.2.1 Pipes and fittings are to be of robust construction and are to comply with
an acceptable National or International Standard, consistent with the intended use.
Particulars of pipes, fittings and joints are to be submitted for consideration.
8.2.2 The design and performance criteria of all piping systems, independent of
service or location, are to meet the requirements of Pt 15, Ch 1, 8.3 Design strength.
8.2.3 Depending on the service and location, the fire safety aspects, such as
fire endurance, flame spread, smoke generation, toxicity and fire protection coatings,
are to meet the requirements of Pt 15, Ch 1, 8.4 Fire performance criteria and Pt 15, Ch 1, 8.5 Additional fire performance criteria applicable to Special Service Craft.
8.2.4 Plastic piping, connections and fittings are to be electrically conductive
when:
- carrying fluids capable of generating electrostatic charges;
or
- passing through hazardous zones and spaces, regardless of the
fluid being conveyed.
Suitable precautions against the build-up of electrostatic charges are to
be provided in accordance with the requirements of Pt 15, Ch 1, 8.6 Electrical conductivity.
8.3 Design strength
8.3.1 The strength of pipes is to be determined by hydrostatic pressure tests to
failure on representative sizes of pipe. The strength of fittings is to be not less than
the strength of the pipes.
8.3.2 The nominal internal pressure, pNi, of the pipe is to be
determined by the lesser of the following:
pNi < 2,5 pst
pNi < 4 plt
where
|
pst |
= |
short term hydrostatic test failure pressure, in MPa |
|
plt |
= |
long term hydrostatic test failure pressure (100 000 hours), in
MPa |
Failure pressures obtained over a reduced period and extrapolated in
accordance with a recognised National or International Standard will be specially
considered.
8.3.3 In service, the pipe is not to be subjected to a pressure greater than
pNi.
8.3.4 The nominal external pressure, pNe, of the pipe, defined
as the maximum total of internal vacuum and external static pressure head to which the
pipe may be subjected, is to be determined by the following:
where
|
pcol |
= |
pipe collapse pressure, in MPa |
8.3.5 pcol is not to be less than 3 bar.
8.3.8 Where it is proposed to use plastic piping in low temperature services,
design strength testing is to be made at a temperature 10°C lower than the minimum
working temperature.
8.3.9 The selection of plastic materials for piping is to take account of other
factors such as impact resistance, ageing, fatigue, erosion resistance, fluid absorption
and material compatibility such that the design strength of the piping is not reduced
below that required by these Rules.
8.3.10 Design strength values may be verified experimentally or by a combination
of testing and calculation methods.
8.4 Fire performance criteria
8.4.1 Where a fire protective coating of pipes and fittings is necessary for
achieving the fire endurance standards required, the coating is to be resistant to
products likely to come into contact with the piping and be suitable for the intended
application.
8.4.2 The materials used for plastic pipes, except those fitted on open decks and
within tanks, cofferdams, void spaces, pipe tunnels and ducts are to have low flame
spread characteristics.
8.4.3 The materials used for plastic pipes within accommodation, service and
control spaces are not to be capable of producing excessive quantities of smoke and
toxic products that may be a hazard to personnel within those spaces.
8.5 Additional fire performance criteria applicable to Special Service Craft
8.5.1 Where plastic pipes are used in systems essential to the safe operation
of the vessel, or for containing combustible liquids or sea water where leakage or
failure could result in fire or in the flooding of watertight compartments, the
pipes and fittings, including couplings with flexible internal seals, are to be of a
type which has been fire endurance tested in accordance with the requirements of
Table 1.8.1 Fire endurance
requirements.
Table 1.8.1 Fire endurance
requirements
|
|
Location
|
| A
|
B
|
C
|
D
|
E
|
F
|
G
|
H
|
I
|
| FLAMMABLE LIQUIDS (f.p. >
60°C)
|
| 1 Fuel oil
|
X
|
X
|
X
|
X
|
0
|
0
|
0
|
L1
|
L1
|
| 2 Lubricating oil
|
X
|
X
|
X
|
X
|
X
|
N/A
|
0
|
L1
|
L1
|
| 3 Hydraulic oil
|
X
|
X
|
X
|
X
|
0
|
0
|
0
|
L1
|
L1
|
| SEA WATER 1
|
| 4 Bilge main and branches
|
L14
|
L14
|
X
|
X
|
0
|
0
|
0
|
N.A
|
L1
|
| 5 Fire main and water spray
|
L1
|
L1
|
X
|
N/A
|
N/A
|
0
|
0
|
X
|
L1
|
| 6 Foam system
|
L1W
|
L1W
|
L1W
|
N/A
|
N/A
|
N/A
|
0
|
L1W
|
L1W
|
| 7 Sprinkler system
|
L1W
|
L1W
|
X
|
N/A
|
N/A
|
0
|
0
|
L3
|
L3
|
| 8 Ballast
|
L3
|
L3
|
L3
|
X
|
0
|
0
|
0
|
L2W
|
L2W
|
| 9 Cooling water, essential
services
|
L3
|
L3
|
N/A
|
N/A
|
N/A
|
0
|
0
|
N/A
|
L2W
|
| 10 Non-essential systems
|
0
|
0
|
0
|
0
|
0
|
0
|
0
|
0
|
0
|
| FRESH WATER
|
| 11 Cooling water essential
services
|
L3
|
L3
|
N/A
|
N/A
|
0
|
0
|
0
|
L3
|
L3
|
| 12 Non-essential systems
|
0
|
0
|
0
|
0
|
0
|
0
|
0
|
0
|
0
|
| ENGINE EXHAUSTS
|
| 13 Main line
|
01
|
01
|
01
|
01
|
N/A
|
N/A
|
01
|
N/A
|
L1
|
| 14 Drain line
|
01
|
01
|
01
|
N/A
|
N/A
|
N/A
|
N/A
|
N/A
|
N/A
|
| SANITARY/DRAINS/SCUPPERS
|
| 15 Deck drains (internal)
|
L1W2
|
L1W2
|
L1W2
|
0
|
0
|
0
|
0
|
0
|
0
|
| 16 Sanitary drains (internal)
|
0
|
0
|
0
|
0
|
0
|
0
|
0
|
0
|
0
|
| 17 Scuppers and discharges
(overboard)
|
01,5
|
01,5
|
01,5
|
01,5
|
0
|
0
|
0
|
01,5
|
0
|
| SOUNDING/AIR
|
| 18 Water tanks/dry spaces
|
0
|
0
|
0
|
0
|
0
|
0
|
0
|
0
|
0 7
|
| 19 Oil tanks (f.p. > 60°C)
|
X
|
X
|
X
|
X
|
0
|
0
|
0
|
X
|
X
|
| MISCELLANEOUS
|
| 20 Control air
|
L13
|
L13
|
L13
|
L13
|
0
|
0
|
0
|
L13
|
L13
|
| 21 Service air (non-essential)
|
0
|
0
|
0
|
0
|
0
|
0
|
0
|
0
|
0
|
| 22 Brine
|
0
|
0
|
0
|
0
|
N/A
|
N/A
|
0
|
0
|
0
|
| 23 low pressure steam (≤ 7 bar)
|
L2W
|
L2W
|
06
|
06
|
0
|
0
|
0
|
06
|
06
|
| NEW SERVICES
|
| 24 Central vacuum cleaning system
|
N/A
|
N/A
|
N/A
|
0
|
N/A
|
N/A
|
N/A
|
N/A
|
0
|
| 25 Exhaust gas cleaning system
effluent line
|
L31
|
L31
|
N/A
|
N/A
|
N/A
|
N/A
|
N/A
|
L31,8/NA
|
N/A
|
| 26 Urea transfer/supply system
(SCR installations)
|
L19
|
L19
|
N/A
|
N/A
|
N/A
|
N/A
|
N/A
|
L31,8/NA
|
0
|
| LOCATION DEFINITIONS
|
| Location
|
Definition
|
| A
|
Machinery spaces of Category
A
|
Machinery spaces of Category A as
defined in Pt 17, Ch 1, 2.4 Ship divisions and spaces 2.4.8.
|
| B
|
Other machinery spaces and pump
rooms
|
Spaces, other than Category A
machinery spaces, containing propelling machinery, boilers, fuel oil
units, internal combustion engines, generators and major electrical
machinery, pumps, oil filling stations, refrigerating, stabilising,
ventilation and air conditioning machinery and similar spaces, and
trunks to such spaces.
|
| C
|
Special category spaces
|
Ro-ro spaces and special category
spaces as defined in SOLAS - International Convention for the Safety of Life at Sea
Chapter II-2 - Construction - Fire protection, fire detection and fire extinction/3.14 and
SOLAS - International Convention for the Safety of Life at Sea
Chapter II-2 - Construction - Fire protection, fire detection and fire extinction/3.18.
|
| D
|
Dry cargo spaces
|
All spaces other than ro-ro spaces
and special category spaces used for the carriage of dry cargo and
trunks to such spaces.
|
| E
|
Fuel oil tanks
|
All spaces used for fuel oil and
trunks to such spaces.
|
| F
|
Ballast water tanks
|
All spaces used for ballast water
and trunks to such spaces.
|
| G
|
Cofferdams, voids, etc.
|
Cofferdams and voids are those
empty spaces between two bulkheads separating two adjacent
compartments.
|
| H
|
Accommodation, service
|
Accommodation spaces, service
spaces and control stations as defined in Pt 17, Ch 1, 2.4 Ship divisions and spaces 2.4.5, Pt 17, Ch 1, 2.4 Ship divisions and spaces 2.4.6 and Pt 17, Ch 1, 2.4 Ship divisions and spaces 2.4.10.
|
| I
|
Open decks
|
Open deck spaces, as defined in
SOLAS - International Convention for the Safety of Life at Sea
Chapter II-2 - Construction - Fire protection, fire detection and fire extinction/26.2.2(5).
|
| ABBREVIATIONS
|
| L1
|
IMO Resolution A.753(18) - Guidelines for the Application of Plastic Pipes on Ships - (adopted on 4 November 1993)Amended
by Resolution MSC.313(88), as
amended by Resolution MSC.313(88) – Amendments to the Guidelines for the Application of Plastic Pipes on Ships (Resolution A.753(18))
– (Adopted on 26 November 2010) and Resolution MSC.399(95) - Amendments to the Guidelines for the Application of Plastic Pipes on Ships (Resolution A.753(18)),
as amended by Resolution MSC.313(88) - (Adopted on 5 June 2015) for a duration of a minimum of one hour without loss
of integrity in the dry condition is considered to meet level 1 fire
endurance standard (L1). Level 1W – Piping systems similar to Level
1 systems except these systems do not carry flammable fluid or any
gas and a maximum 5% flow loss in the system after exposure is
acceptable (L1W).
|
| L2
|
Level 2. Piping having passed the
fire endurance test specified in Appendix 1 of IMO Resolution A.753(18) - Guidelines for the Application of Plastic Pipes on Ships - (adopted on 4 November 1993)Amended
by Resolution MSC.313(88), as
amended by Resolution MSC.313(88) – Amendments to the Guidelines for the Application of Plastic Pipes on Ships (Resolution A.753(18))
– (Adopted on 26 November 2010) and
Resolution MSC.399(95) - Amendments to the Guidelines for the Application of Plastic Pipes on Ships (Resolution A.753(18)),
as amended by Resolution MSC.313(88) - (Adopted on 5 June 2015) for a
duration of a minimum of 30 minutes in the dry condition is
considered to meet level 2 fire endurance standard (L2). Level 2W –
Piping systems similar to Level 2 systems except a maximum 5% flow
loss in the system after exposure is acceptable (L2W).
|
| L3
|
Fire endurance test in wet
conditions, 30 minutes, IMO Resolution A.753(18) - Guidelines for the Application of Plastic Pipes on Ships - (adopted on 4 November 1993)Amended
by Resolution MSC.313(88)
Appendix 2 - Test Method for Fire Endurance Testing of Water-Filled Plastic Piping.
|
| 0
|
No fire endurance test
required.
|
| N/A
|
Not applicable.
|
| X
|
Metallic materials having a
melting point greater than 925°C.
|
|
Note 1.
Remotely controlled valves are to be provided at ship’s
side. Valve is to be controlled from outside space. Where the
valve is located below the SWL, the operating position is to be
above the freeboard deck.
|
|
Note 2. For
drains serving only the space concerned, ‘0’ may replace ‘L1’.
|
|
Note 3. When
controlling functions are not required by the Rules or statutory
requirements, ‘0’ may replace ‘L1’.
|
|
Note 4. For
passenger craft, ‘X’ is to replace ‘L1W’.
|
|
|
|
Note 6. For
essential services, ‘X’ is to replace ‘0’.
|
|
Note 7. Air
and sounding pipes are to be located in a sheltered position,
and protected from mechanical damage.
Note 8. L3 in
service spaces, N/A in accommodation and control spaces.
Note Type Approved plastic piping without fire endurance test (0)
is acceptable downstream of the tank valve, provided this valve
is metal seated and arranged as fail-to-closed or with quick
closing from a safe position outside the space in the event of
fire.
|
8.6 Electrical conductivity
8.6.1 Where a piping system is required to be electrically conductive for the
control of static electricity, the resistance per unit length of the pipe, bends,
elbows, fabricated branch pieces, etc. is not to exceed 0,1 MΩ/m.
8.6.2 Where a piping system is required to be electrically conductive for the
control of static electricity, electrical continuity is to be maintained across the
joints and fittings and the system is to be earthed. The resistance to earth from any
point in the piping system is not to exceed 1 MΩ. See also
Pt 16, Ch 2, 1.13 Electrical bonding for the control of static electricity.
8.7 Manufacture and quality control
8.7.1 All materials for plastic pipes and fittings are to be approved by LR, and
are in general to be tested in accordance with Ch 14, 4 Plastic pipes and fittings of the Rules for the Manufacture, Testing and Certification of Materials, July 2022. For pipes and fittings not employing hand lay up techniques, the hydrostatic
pressure test required by Ch 14, 4.9 Hydraulic test of the Rules for the Manufacture, Testing and Certification of Materials, July 2022
may be replaced by testing carried out in accordance with the requirements stipulated in
a recognised National or International Standard, consistent with the intended use for
which the pipe or fittings are manufactured, provided that there is an effective quality
system in place complying with the requirements of Ch 14, 4.4 Quality assurance of the Rules for the Manufacture, Testing and Certification of Materials, July 2022
and the testing is completed to the satisfaction of the LR Surveyor.
8.7.2 The material manufacturer’s test certificate, based on actual tested data,
is to be provided for each batch of material.
8.7.3 Plastic pipes and fittings are to be manufactured at a works approved by LR
in accordance with agreed quality control procedures which shall be capable of detecting
at any stage (e.g. incoming material, production, finished article, etc.) deviations in
the material, product or process.
8.8 Construction and installation
8.8.1 All pipes are to be adequately but freely supported. Suitable provision is
to be made for expansion and contraction to take place without unduly straining the
pipes.
8.8.2 Pipes may be joined by mechanical couplings or by bonding methods such as
welding, laminating and adhesive bonding.
8.8.3 Where bonding systems are used, the manufacturer or installer shall provide
a written procedure covering all aspects of installation, including temperature and
humidity conditions. The bonding procedure is to be approved by LR.
8.8.4 The person carrying out the bonding is to be qualified. Records are to be
available to the Surveyor for each qualified person showing the bonding procedure and
performance qualification, together with dates and results of the qualification testing.
8.8.5 Conditions during installation, such as temperature and humidity, which may
affect the strength of the finished joints, are to be in accordance with the agreed
bonding procedure.
8.8.6 The required fire endurance level of the pipe is to be maintained in way of
pipe supports, joints and fittings, including those between plastic and metallic pipes.
8.8.7 Where piping systems are arranged to pass through watertight bulkheads or
decks, provision is to be made for maintaining the integrity of the bulkhead or deck by
means of metallic bulkhead or deck pieces. The bulkhead or deck pieces are to be of
substantial construction and suitably protected against corrosion and so constructed to
be of a strength equivalent to the intact bulkhead; attention is drawn to Pt 15, Ch 1, 8.8 Construction and installation 8.8.1, details of
the arrangements are to be submitted for approval.
8.8.8 Pipes or other fittings attached directly to the plating of tanks and to
bulkheads, which are required to be of watertight construction, are to be secured by
means of studs screwed through the plating or by tap bolts, and not by bolts passing
through clearance holes. Alternatively, the studs or the bulkhead or tank pieces may be
welded to the plating.
8.9 Additional requirements for testing plastic
pipes for Special Service Craft
8.9.3 In the case of pipes intended for essential services each qualified person
is, at the place of construction, to make at least one test joint, representative of
each type of joint to be used. The joined pipe section is to be tested to an internal
hydrostatic pressure of four times the design pressure of the pipe system and the
pressure held for not less than one hour, with no leakage or separation of joints. The
bonding procedure test is to be witnessed by the Surveyor.
|