VoyForums
[ Show ]
Support VoyForums
[ Shrink ]
VoyForums Announcement: Programming and providing support for this service has been a labor of love since 1997. We are one of the few services online who values our users' privacy, and have never sold your information. We have even fought hard to defend your privacy in legal cases; however, we've done it with almost no financial support -- paying out of pocket to continue providing the service. Due to the issues imposed on us by advertisers, we also stopped hosting most ads on the forums many years ago. We hope you appreciate our efforts.

Show your support by donating any amount. (Note: We are still technically a for-profit company, so your contribution is not tax-deductible.) PayPal Acct: Feedback:

Donate to VoyForums (PayPal):

[ Login ] [ Contact Forum Admin ] [ Main index ] [ Post a new message ] [ Search | Check update time | Archives: 1, [2], 3, 4 ]

[ Next Thread | Previous Thread | Next Message | Previous Message ]

Date Posted: 14:19:58 10/14/06 Sat
Author: 何焯華條賓周+歡迎炸佢: jameslam@hkpro.com.hk
Subject: 淨屌何焯華條仆街呢+歡迎炸佢: nancychow@hkpro.com.hk
In reply to: 何焯華條賓周+歡迎炸佢: jameslam@hkpro.com.hk 's message, "淨屌何焯華條仆街呢+歡迎炸佢: nancychow@hkpro.com.hk" on 14:15:21 10/14/06 Sat

b) Copper pipes up to and including 54mm bore shall be assembled wi 由 capillary fittings by "Yorkshire Imperial Metals Ltd." or provided equal. Fittings shall be in compliance wi 也
B.S.864 : P 訂 t 2 : 1971.


c) Upon receipt the approval 企 om 也 e Surveyor, copper tubing up
ω and including 中 28mm may be bent wi 由組 approved type of


PS-27

SPECIFICATION ‘ A' -PARTICULAR

bending machine and 也 e bends as formed is entirely 企 ee 企 om bucking 組 d excessive 也 inning of the pipe wall.

PS-28

SPECIFICATION ‘ A' 一 PARTICULAR

d) All copper tubing exceeding 中 28mm shall be fi說 edwi 也 elbows
and bends. Whenever possible, bends shall be used in
preference to elbows. Pipes exceeding 54mm shall be jointed by means of br, 位 ed or bronze welding joints and su 伍 cient pairs of welded gunmetal flanges must be installed to facilitate dismantling gunmetal 且也 ges shall be 血紅 lufactured in accordance with B.S.I0 Table E and welded to 也 e pIpe. Flanged join 的 shall be flush 組 d 甘叫 y aligned and shall be uti! 泣 ed approved g 訟 ket rings made of natural rubber coated on bo 由 sides wi 也組 approved jointing compound. All bolts shall be hexagonal-headed brass in accorl 也 nce with the provisions of B.S.28 for washers and nuts. The welding me 也 od shall be in compliance wi 白白 e relevant welding codes and specifications of clause 'Welding and Brazing'.

e) Copper tubing is to supported by cast brass pipe brackets of approved pa 位 ern.

7.3 Galvanized Steel Pipe

a) Galvanized steel pipes shall be in accordance wi 也 B.S.1387 :
1967, medium grade 組 d capable of withstanding a hydraulic
test.pressure of 49.30kg/cm2.

b) Fitting for galvanized steel pipes shall be galvanized malleable cast iron pipe fi 社 mgs 的 B.S.143 and B.S.1256 including bends, elbows, tees, crosses and sockets, equal of reducing as required, true to shape, properly 也 readed and s 出且位ω B.S.1740.

c) Galvanized steel pipes up to 80mm bore may be assembled
WI 也 screwed j oinu 弓 , pipes of 100mm bore and larger shall be
jointed wi 也 screwed on galvanized steel flanges.

d) Flanges shall be galvanized mild steel to B.S.I0 Table 'E'. All fl 缸 19ed joints shall be flush and 甘 uly aligned, and shall utilize approved pI 前 n gasket rings, coated on both sides with an approved j ointing compound. All bolts shall be hexagonal- headed galvanized or cadmium coated steel, in accordance with the provisions of B.S.28, wi 也 washers and nuts of identical finish 的 bolts.

e) All screwed joints shall be made in accordance with the provisions ofB.S.21, 組 d shall be clean 由 readed, pulled up tightly and made wi 也 unsintered PTFE 旭 pe for 也 read sealing applications to B.S.4375 : 1968. No welding is allowed on galva 且 ized steel pipework.

PS-29

SPECIFlCA TION ‘ A' 一 PARTICULAR

f) Where plant or valves have 宜 anges of equal ω B.S. s 個且包 rd
直個 ges, matching flanges shall be ins 臼 lIed.

g) All G.S. pipes which come into direct contact with concrete or are buried underground shall be coated wi 也 2 co 的 of bi 臼血俗世 c solution and wrapped wi 也組 approved po lye' 也 ylene or PVC se 匠 adhesive 阻 pe s 凶 il 位 to "Denso". The overlap shall be 25mm minimum. Such pipework must be inspected by a representative of the Water Au 也 ority before it is backfilled or covered.

7.4 Rigid Unplastic 包 ed PVC Pipe for Flushing Water Supply System

a) Rigid unplasticized polyvinyl chloride tubings 組d fittings for
water supply service and general purpose shall be in accordance to B.S.3505 class E wi 也 standing a sustained working pressure of 15 bar for pipe sizes up t 。但 5mm 組 d to B.S.3S0S Class D WI 也 s 個 nding a sustained working pressure of 12 bar for pipe
sizes above 中 2Smmand up ω中 IS0mm at a temperature of 20 ° C, or in accordance wi 也 Japanese Industrial S 臼 nd 訂 d ns 6742 Class VP, and of the following nom.inaI sizes, wall 也 ickness 組 d weigh 紋 ,

b) Pipe fittings shall be to B.S.4346 : P 訂 t I or nS6743 and to be
specially made for use wi 曲曲 e 個 bing.

c) The tubing is to be jointed by 'Solvent Welding' method wi 也 socket in accordance wi 也 the m 缸 lufacturer's ins 甘 uctions 'Sleeve' me' 也 od for jointing pipes is not acceptable.

d) Bends in pipes of less 也組柯 Omm may be formed by filling the 如 be wi 也 sand, submersed the entire surface into oil which is gently heating up to approximately 130 ° C, bending the tube to the required shape and 也 en cooling wi 也 water.

PS-30

SPECIFICA TION ‘ A'-PARTlCULAR

e) UPVC tubing to be secured with PVC coated galvanized steel pipe brackets of approved pa: 借此 Brackets must be fixed in such a way so as to allow expansion and ex 仕 action of 也 e tubing wi 也 out causing any damage to 也 e pIpe.

PS-31

SPECIFICATION ‘ A' 一 PARTICULAR


7.5 Ductile Iron Pipe


a) Ductile iron pipe to be B.S.4772 classK12 for above ground wi 也
cement lined internally and bitumen ∞ ated ou 臼 ide.


b) Fittings to ductile iron pipes are to correspond in pa:吐 em and
也 ickness wi 也 the pipes and be purpose-made if required.


c) Ductile iron pipes and fittings 位e to be B.S. 4772, cement lined
internally abd bi 如 m 組∞ ated outside 組 d flanges.


d) The minimum weights of v 缸 lOUS S 泣的 of pipes 位 e to be as follows:-


Dia of tube E泣ernal Wall
Diameter Thickness
(mm) (mm) (rom)
80 98 7.0
100 117 7.2
150 169 7.8
7.6 Installation of Pipe Work


a) All plumbing work shall be carried out by an approved licensed
plumber and by 組 approved licensed plumber and registered contractor in compliance wi 也 the requirements of the Water Authority and Building Au 也 ority. Approval and consent shall be obtained prior to commencement of any installation work.


b) All pipes shall run in wall, 宜。 or screeds or pipe duc的 unless
。由 en 社 se specified. Pipe and fittings exposed to view in bathroom and lavatories shall be chromium plated.


c) Pipework shall be carefully arranged to a neat and workmanlike
appe 訂 ance m 甘 ue all 伊 ment with a minimum number of crossovers.


d) Disconnecting fl 個 ged or screwed unions shall be provided at valves and fittings and at suitable locations for cleaning and removal of piping.


e) All pipework shall be free 企om burrs, rust, and scale and shall
be thoroughly cleaned before erection. Open ends during 也 e progress of work shall be blanked-o 宜 with purpose-made metal or plastic caps and the use of wooden plugs is forbidden. Should any stoppage in 也 e flow occur after 也 e various systems have been put into operation, owing to non-compliance with


PS-32

SPECIFICATION ‘ A'-PARTICULAR

也 is requirement 台也 e Sub-Con 甘 actor shall recti 有 r the fa 叫 tat 趾 s own expense.

。 Pipes are 的 be in反 alled wi 也 correct falls for venting and
dr 洹 ning and atten 世 on must be paid to nea 包 ess of ins 個 llation. Groups of pipes to be accurately spaced 組 d valves, joints, etc. symmetrically 位 ranged. Where 趴 TO or more pipes are visible andcha 且 ge directian together, bends shall be s 仕 uck 企 om a comman radius paint. Adequate clearances ta be maintained in all cases to allow for the applicatian 'Of 也 e insula: 世 on 組 d finishing.

g) Suspended pipework must be positioned as close ta slab soffits
臼 possible, unless shown 0 也 erwise an the Drawings, whilst maintaining required falls.

h) All pipework likely ta be in direct cantact with concrete shall be ∞ ated wi 也 a bitumen compound and wrapped in poly 也 ene before being concealed.

i) Vertical s 旭 cks must be pasitioned as hard against ta wall
∞ lumns 組 d fins as possible.

j) Valves etc. should be installed. in such a manner 也 at fu仙 re
m 位 ntena 且 ce of glands etc. is made as e 路 y as possible. All hand wheels must also be accessible.

k) Cross relief vents are to be provided an sail stacks at 也 e flaor levels nated on the diagrams. Cannections ta sail s 個 cks 訂 e ta be made belaw the lawest branch serving the flaar and 也 e upper end is ta jain 也 e vent stack not less 也 an 700mm abave flaar level.

7.7 Potable Water Supply System

a) τ be system shall commence at the nearest city main connectian
'Or as shawn an the Drawings.

的 The system shall include pipings far bath cald and hot water in a direct 'Or indirect supply system if electrical water heater or gas water heater is installed.

c) Unless 'Otherwise specified, ductile iran pipes shall be used far 由 e nser main ta water tank and capper tubes shall be used far dawn feed pipes 企 om waterta 且 kin 也 is system.

d) All pipes of 也 is system shall run in either walls, flaar, screeds
'Or pipe ducts, and shall apply ta the Surveyor for instructian

PS-33


SPECIFICATION 'A' 一 PARTICULAR
before commencement of work if he finds any pipe which cannot be satisfactorily concealed.
e) This system shall be carried out and provided in accordance
WI 也 anyone or more of the plumbing diagrams.
7.8 Flush Water Supply System
a) The system shall commence at the nearest salt water main or city water main as described in the Specification or shown on 也 e pI 個 s.
b) All flush water pipe shall run in wall, 宜。 or screeds, or pipe ducts and shall inform 也 e Surveyor and ob 扭扭 his approval in writing for 組 y pipe which cannot be concealed.
c) This system shall be carried out and provided in accord 組 ce
WI 也 the plumbing line diagram.
d) Unless otherwise specified, 也 e whole system shall be of 也 e
following materials.
i) 中 25mm t。“ Omm delivery pipes serving the same purposes
shall be PVC pipes to B.S.3505 Class D or ns 6742 Class VP.
e) Unless otherwise specified, sizes of down pipes shall be as follows:-
Number of F1ushin!!" Cisterns
Dia ofPioes (mm)
1-3 4-7
8-11
12 -23 20 -40 40-60 Over 60
0500050
吋 -4 弓 ,hqdA 『 FD ζ u 。。
7.9 Pipe Fitting






























a) On all systems (except where limited by space) long radius bends and pitcher tees 訂 'e to be used. All fittings 訂 e to be suitable for the working pressure not lower 也 a 且也 at specified for the pipework system concerned.


SPECIFICATION ‘ A' 一 PARTICULAR

Reductions in bores of pipes to be made eccentric for horizontal pipes (to prevent air loc 垣 ng) and taper fittings 缸 e to be fitted for vertical pipes. S 個 n 街 rd reducers 位 e to be used unless approved otherwise.

的 G.1. fittings for pipes up 的 and including 50mm bore to be screwed malleable iron wi 也 banded ends using an approved sealing compound. The use of _plumbers rope and improperly cut 也 reads is deprecated and will be rejected. Above 50mm bore fittings shall be flanged, all fi' 吋 ngs for galva 且 ized pipes are to be galvanized.

c) All unions shall have ∞ me 祉 ground se 的 and all screwed JO 恆的 shall be made in accor 街 nce WI 也 the provisions of B.S.21 and shall clean 由 readed, pulled up tightly and made with and approved jointing compound and fine stranded hemp.
d) Pipe Jointing Materials

Jointing materials to be as follows:-

i) Jointing materials generally to be of types recommended by the
manufac 仙 rer of the pipe being jointed.

的 Pipe 由 read tape to be "PTEE" of an approved proprietary brand 組 d shall comply wi 也 the requirements ofB.S.4375. Spun y 缸 n or hemp used in screwed socketted joints or screwed on flanged
joints will not be permitted.

iii) Lead used in cast iron pipe spigot and socket joints shall be of molten lead. No asbestos or asbestos products will be allowed for j ointing materials.

iv) Gasket used in cast iron pipe spigot and socket joints shall be of
tarred spun yarn hemp.

v) Mortar is to be mixed by mechanical mixer or by hand on a clean, close-boarded platform 組 dwi 也 a proportion of 1:3 cement and sand.

vi) Cold ca叫姐 ng compound to be "Philplug" PC3 or PC4.

vii) Jointing compound for screwed joints to be 官 oss-white" .

viii) Jointing rings for flanged pipes ω be of copper sheet with
concentric corrugations.

ix) Join也 g p 路 te for flanged joints to be of 組 approved
proprietary brand.

PS-35

SPECIFICATION ‘ A' 一 PARTICULAR

7.10 Pipe Supports

a) All pipework, fittings, valves, connections etc. shall be su 伍 ciently supported and bracketed. All pipework shall be supported at intervals not greater 也 a 且也 e following on s 仕 aight runs, additional supports shall be provided at bends, valves, etc. or where specified and required by the Surveyors:-


Nominal Bore of Meters pIpe
但 _
15 20 25 32 40 50 65 80
100 150


Galvanized Steel, Black steel & Pressurized UPVC Pipes
D 旦 ctil 立 _c.?p._ PJP. 竺 ----------
_ _ ___'!l_ {:的 Interval 倍 )--------------
Vertical Horizontal Vertical Horizon叫

1.8 1.2 1.5 1.0
2.1 1.5 1.5 1.0
2.1 1.8 1.8 1.2
2.4 1.8 1.8 1.2
2.4 2.1 2.1 1.5
2.4 2.1 2.1 1.5
2.4 2.1 2.1 1.5
2.7 2.4 2.4 1.8
2.7 2.4 2.4 1.8
3.0 2.7

PS-36


SPECIFICATION ‘ A' - PARTICULAR
Stainless封閉 __Jp. 笠 - -
Interval 包 t_____
df
no
xxm ‘回 732852476839-
M 歐到一 , 但一 12234567 ω泊的一
Vertical Pipes
1.5 1.5 1.8 1.8 2.1 2.1 2.1 2.4 2.4 2.4 2.7
叫
nUFB
O 挖一 99225558884
El--
TU 而 }OOl--111112
0]
H
No 凶 nal Bore of Pipe (nun)
80 100 150 225
300 & above
Cast Iron Dr卻也 e/Sew 銘呀 !P_____
且啟立型的 t__
Ve而 cal P 掙 es Horizontal
f!_ 笠
1.8 1.8 1.8 1.8 1.8 1.8 2.1 2.4 2.5 3.0
Nomin 剖 Bore of Pipe
(mm)
32 40 50 65
80
100 150
- --虫也 Dra 駝背 ? 堅強 _iQ___
In' 吱吱位但 )---
Vertical Pipes
1.2 1.2 1.8 1.8 1.8 1.8 1.8
Notes: ﹒
Horizon 包 I
Pipes
0.6 0.6 0.9 0.9 0.9 0.9 0.9
No less 也組 2 supports must be used on all pipes having leng 也 s less than the minimum intervals indicated.
b) For UPVC pipes in vertical installation, only the anchor shall rigidly clamp the pipe, the remaining "c" clamp or split pipe rings spaced at intervals in above table shall only cons 甘吋且 也 e pipe in lateral direction but shall allow 企 ee movement along the axis of the pipe. These metal clamps or rigs shall be lined wi 也
UPVC sleeve.
PS-37

SPECIFICATION ‘ A' 一 PARTICULAR

UPVC pipes used for 個 nk overflows, 世垣 ns etc. shall be adequately supported such 也 at no deflection of pipe 0 ω urs.
c) All supports for steel pipes including unplasticized PVC shall be fe 叮 OUS.

d) All supports for ∞ pper pipes shall be brass. Where copper pipes are installed wi 也 other pipes and a single ferrous support is used, a PVC sleeve shall be provided at the point of contact.

e) Unless 0由 erwise spec 也吋 allhange,郎 , support and brackets for steel or
iron pipes and unplasticized PV C pipes shall be stainless steel and for UPVC pipes all brackets shall be sheathed with plastic collar. All bolts, nuts and washers shall be s 扭扭 less steel.

e) All pipe supports 訂e to be of such design 組 d 可 pe as to allow
for the removal of a 且 y pipe section without 也 e necessity of disconnecting other ac\ 仰 ent pipes.

f) Where pipe rings are used they 訂 e to be split pattern wi 也 top
and bottom bolts. F or horizontal pipes the rings shall be held by mild steel rod screwed to pipe ring boss and in all cases where rocking movement of the pipe ring is expected spherical seating washers shall be provided to all adjusting nu 臼 .

g) In pump room 訂閱 all pipe supports shall incorporate resilient rubber-in-shear pipe mountings ω prevent vibration being t 缸 lSIDl 位 edtos 仕 ucture.

h) The discharge pipework form pumps 組 d all pipework where vibration could be 甘 ansmitted to the Building structure shall be supported with brackets etc. which shall have tough rubber washers at contact of bracket to pipe.

i) All supports etc. fixing to concrete s 仕 uctures shall be by using
of Philips red-head bolt fIXing or approved equivalent for concrete and cu 吋 ng away and building in of brackets in brickwork etc. The Sub-Con 甘 actor is to particularly not 也 at it will not be possible to fix bolt fixing directly above the pipes to be supported, in such event, cantilever brackets shall be used where required.

j) External pipe brackets shall be primed wi 也 one coat of 組ti-
corrosive paint prior to ins 個 llation.

7.11 Pipe Sleeves

a) Where pipes pass 也 rough walls, 宜。 ors, ceiling, etc. the
plumbing Sub-Con 甘 actor shall provide and fixed 也 e pIpe

PS-38

SPECIFICA nON ‘ A' 一 PARTICULAR

sleeves at the ac' 個 a1 positions. Sleeves for cast iron and galvanized iron pipes shall be black steel; for copper pipes shall be either copper or brass. All sleeves a: τ 'e fi 位 ed 也 rough floors, they shall extend to at least 6mm clear of finished floor.

b) Sleeves shall be of slightly oversized to allow 企 ee movement of pipes.

c) The Sub-Con甘actor's attention is drawn ω the vertical pipe
ducts. At all floor levels in 也 e building, 也 e ducts are 的 have floors and where pipes pass 也 rough these, sleeves are to be provided.

PS-39

SPECIFICA nON ‘ A' 一 PARTICULAR

d) The gap between pipe 組d 也e sleeve is to be packed wi 也
figreglass blanket material. However, for pipes/sleeves 也 rough fire barrier the gaps must be firmly sealed wi 也 soft packings having a period 'Of fire resi 位組 ce equal to 也 e fITe barriers. The ends of sleeves are to be caulked with nan-hardening mas 世 c to Surveyor's approval.

e) Details of pipes 也 rough walls and 宜。 ors ta be appraved by 由 e
Fire Services Depar 虹 nent and the Surveyor before ins 個 llation.

7.12 Pipe Anchors

a) All pipes shall be anch'Ored as required to con仕'01 the movement
of pipes due t'O thermal charges.

b) The anchors shall securely hold the pipe in a rigid positian to resist 也 e attempted movement due to expansion and the weight of the pipe and contents.

7.13 Cocks and Valves

a) General

i) All cocks and valves shall be of the type approved by 也 e Water
Au 也 ority for their various purposes, capable of withstanding a hy 企 a 叫 IC wor 屆時 press 叮 e of not less 由組 12 BAR and InS 臼 lled in accessible positions for ease of operation 組 d maintenance.

ii) All valves shall be arr組ged so 也 at cl'Ockwise rotatian of the
spindle will close the valves.

ill) All valves exposed to view in lavatories shall be chromium
plated unless 'Otherwise specified.

iv) All valves installed in the flushing systems shall be of sea water
carroslon reSIS 個 nee type.

b) Draw 'Off Taps

i) Draw 0 宜 taps for potable water supply system shall be brass
組 d 也 at for flushing water supply system shall be zinc 企 'ee br'Onze 'Or gunme 個 1.

PS-40

位 ) Unless 0 由 erwise specifie_ screwed down or spring 句 rpe action
bib and pillar cocks shall be either brass or zinc 企 'ee bronze, chromium plated wi 也 cap 位組 head marked "Hot" or "Cold" and conforming to B.S.IOI0.

c) Stop Cocks and Valves
All stop cocks and valves not exceeding中50mm shall be bronze
WI也crutch head conforming to B.S.1010 for potable water
system.
位) UPVC stop cocks shall be wi也wheel head conforming to JIS-
B2212 and shall be suitable for a working pressure of 9 BAR.
The stop cocks shall be en:世rely suitable for use wi由sea water.
Samples shall be submitted for approval.
111、)區 All s的p valves for企esh/potable組d flushing water supply
system exceeding _ 50mm shall be flanged c訟t iron globe
valves wi也wheel head conforming to B.S.3961.
iv) Loose jumper type rough 倒shwi也easy de組cover brass stop
cock to B.S.1010, to be used where indicated by也e Water
Authority.
v) Drain cocks must be provided wherever required to ensure that
every section of pipework can be世位ned.
vi) In particular cocks must be provided on the rId臼d" side of non-
return valves, and isolating valves on the mains.
d) Gate Valves
Gate valves up to and including 65mm bore shall be of
gunmetal construction fullway solid wedge pa吐:em to B.S.5154.
All valves shall have inside screw gate,趾gh tensile bro位e
spindle and screwed bonnet. Valves shall have screwed female
ends.
11、J ‘I Gate valves of 80mm bore and over shall be flanged cast-iron,
fullway sl凶∞WI由inside screw solid wedge and趾gh tensile
bronze spindle to B.S.5163. Valves shall have bolted bonnets.
Valves fitted凶valve pits shall have spindle with square head
and operating keys shall be provided, other valves to be cast
iron hand wheel to B.S.1218.

PS-41

SPECIFICA nON ‘ A' - PARTICULAR

iv) All gate valves to be suitable for a test pressure of not less th 組
的 BAR.

v) Gate valves for flushing water system shall be fullway valves with external rising screw, 宜 anged or screwed to suit the piping and shall be of cast iron cons 甘 uction wi 也 nickel alloy faces and S 扭扭 less steel spindle to B.S.3464. Valves shall be supplied by Glenfield and Kennedy or approved equal, full suitable and approved for use wi 也 sea water.

e) Ball Valves and Floau 弓

i) Ball valves up to and including 中 65mm 組 d using in potable
water supply system shall be brass conforming to B.S.1212 with copper float to B.S.1968.

ii) Ball valves up to and including 中 65mm and using in flus 趾 ng water supply system shall be zinc 企 ee bronze conforming to B.S.1212 with plastic float to B.S.2456.

iii) Ball valves of 祕 Omm and above shall be of the Glenfield and Kennedy type fig. no. 1005* wi 由 cast iron valve body wi 也
nickel alloy and stainless steel working p 訂的 . The valves for flush water shall have construction entirely suitable for use with sea water and floats shall be copp 位 WI 也 neoprene coating. ( or equal and approved to relevant British Standard.

iv) Ball valves shall be of 血 e slow closing type as spec 也 ed above.

。 Check Valves
i) Check valves shall be bronze wi 也 square nut head conforming to B.S.5154 for potable water system and zinc 企 ee bronze for flushing water system.

ii) For check valve on the discharge side of potable and flushing water pumps, with the discharge outlet over 中 50mm, the check valve shall be either one of the following:-

1. "Vag" cast iron resilient diap 趾 agm 可 pe check valves.
何 or 組 ng pressure 16 b 缸 . and W. Germany origin).

2. "GLEMFIELD" RECOIL CHECK VALVE - shall be
cast iron recoil single dish 可 pe figure nos. M7 s (working pressure 14 BAR) and 5101 (working pressure 16.33 BAR) and of U.K. origin.

PS-42

SPECIFICATION' A' - PARTICULAR

g) Pressure Reducing Valves (for Fresh and Flushing Water)

i) Pressure reducing valves shall be of adjustable sp也 19 type
liB 位 ley's" T pressure regulator or approval equal, cast iron body, ZInC 企 ee bronze trim fully suitable for salt water, slow closure and 也 mped to ens 叮 'e smoo 也 operation without sl_mm;ng.

ii) Valve to be protected by 60 mesh monel metal screen "Y" or "T" 可 pe s 甘位 nerm 計 alled upstream. S 仕 ainer tQ be fully suitable for use on sea water. Reducing valve assembly to be ins 個 lled in a readily accessible location close to 也 e down-feed mains.

也 ) One(l) 的 mm dial press 叮 e gauge (scale 0- 3 5bar) to be installed at 由 e upstream immediately-down-stream of 也 e valve, with valve cock to read con 甘 olled press 叮 'e.

vi) All press 叮'e reducing valves to be approved by Water Authority.

7.14 Welding and Brazing

a) Welders must have a current certificate 'Of cQmpetency and in addition will be required to perform site tests of competency, should a welder fail such tests he shall replaced.

b) The Surveyors reserve the right to c 叮叮 out welding tests 'On up to 2% of the welds 'On the installatiDns. The CDntractor shall include for remaking 也 e jDints where CutDut. Should the results of these tests indicate that the welds are nDt to the requirements of 也 is specificatiDn 也 e CDn 仕 actor shall, 正 instructed, remove all pipe-work and welds perfDrmed by 也 e welder and replace the work and pay all CDsts incurred by other CDntractors (if affected) withDut any additional charge.
c) All pipework for welding shall be supplied with plain ends,
joints being made wi 也 butt welds on the site. All welded joints shall be made by an apprDved welding process, each joint being of sufficient s 仕 ength to wi 也叫 and 也 e s 甘 esses imposed by internal press 叮 e, 企 om 也 e expansiDn, weight 'Of tube, and contents and 也 e thermal insulatiDn.

d) All welded tees, branches, vent pipes, reducers, etc. shall have bevelled, mi 仕 edjDints, fused by a pene 仕 ation weld and finished off with a fillet weld of ample dimensions. Care shall be taken to ens 凹 e 也 at 由 e welding metal or flux does not project intD 也 e bore 'Of 也 e pipe.

PS-43

SPECIFICA nON ‘ A' 一 PARTICULAR

。 All welds shall be of good clean me叫 , 企臼企om slag
inclusions and porosity, of even 也 ickness and regular contour, well fused wi 也由 ep 訂 'ent me 臼 1 and 徊的 aled and hammered on completion 組 d 直到 shed smoo 也越 I cuts 企 om 到扭曲 rd len 阱 s of pipes shall be made by means of hack-saw, 組 d burrs removed wi 也 reamer and the ends 甘 immed to a fair faced joint for welding. Each weld on black steel pipe shall on completion be painted wi 也 a coat of red oxide.

。 Copper pipes shall be ei 也 er br,位 ed or bronze welded to an
approved technique to B.S.1723 組 d B.S.1724. 也 e welding rods to be of a 可 pe that is suitable for pipe material, contents and atmospheric conditions. All oxy-acetylene welding shall be 泊 a ∞ or 也 n 臼 to B.S.4872.

g) Welded pipe jo 恆的 shall be permitted on pipes up ω 150mm nominal • bore only in situations where flanged joints are deemed by the Surveyor to be impossible or impractical.

的 Steel pipes having welded jo 恆的 on the run shall be prep 訂 ed for join 世 ng in a manner suitable for the technique employed. Welding may, alterna 世 vely be carried out by oxyacetylene flame, or by electric metal-arc methods.

i) Oxyacetylene welding shall be by 也 e Rightward technique as
described in Technical Memorandum T.5 issued by the British Welding Research Associa: 世 on 組 d B.S.2640. Pipes shall be prep 訂 ed for welding with ends sawn or cut off by hand, flame cut by machine of flame cut by hand wi 也 subsequent 甘 umgup by filling or by gr 旭 ding to a level as may be required. Welding rods shall in all cases, be of good quality copp 位 coated low carbon steel, and the manufacturer shall provide test certificates representative of the rods used in accordance with B.S.1453.

j) Welders identification works required 的 be stamped at each weld.

k) Metal arc welding shall be carried out in accordance wi 自由 e techniques described in Technical Memorandum T.3. issued by
the British Welding Research Association and B.S.2633 : 1973 :
Class I or B.S.2971 : 1961 : Class 2, butt ends to piping being built up on ei 也 er a base run deposited by 也 e oxyacetylene pro 臼 ss or a permanent mild steel backing ring. Electronics shall be of good quality in accordance with B.S.639 : 1976, be coated and be of such diameter 由 at perform 個 ce may easily be controlled to produce a weld of the required quality. All slag shall be removed after each run, undercut edges, slag pockets unsound metal and blowholes being chipped out as the work pro 臼 eds.

PS-44

一一一一一

SPECIFICATION ‘ A' 一 PARTICULAR

1) All welded joints, whe也 er produced by oxyacetylene flame or
me' 值 1- 訂 c processes shall be of first quali 旬 , the butts being slightly convex with regular ripples and no undercutti 時 , washing away or surface cavities being present. Notches at the root indicating incomplete penetration and excessive weld pro 甘 uding into 也 e pipe bore in excess of 1.6mm inch shall not occur and 也 e external reinforcement shall run out smoo 也 ly to the pipe surface on ei 也 er side.

m ) Welding shall in all cases be carried out by skilled cra丘 smen
who are in possession of a current certificate of competency issued by an approved au 也 ority. The provisions of specimen welds, representative of the thickness and diameter of 也 e joints 組 d 也 e conditions of site welding shall be submitted as req 世 red by the Surveyor in respect of every craftsman employed in such work.

PS-45

SPECIFICATION 'A' 一 PARTICULAR

n) When 也 e general hydraulic tests of the completed sy到 ems are
carried out, as detailed elsewhere each weld shall be lightly hammered during 也 e time 也 at press 前 e is main 切 ined. 在組 y leaks occur at welds 也 e portion of 也 e weld near the leak shall be cut out and re-welded. Such leaks shall not be repaired by ca 叫垣 ng or attempted fusion of 也 e surround metal. Should a considerable portion of 也 e welded joints be made by a p 訂 ticul 訂 operator be found to be defective due to fa 叫 ty workmanship, all such welds shall be cut out and re-welded by ano 白白 operator whose work has proved satisfactory.

7.15 Jointing of Concrete Pipes

a) For spigot 組d socket pipes, the spigot shall be placed in the
socket of the pipe previously laid, and the pipe 也 en adjusted and fixed in its :final position to correct lines and levels and accurately centered. A ring of 泊的 d rope-yarn shall be next inserted in the socket of the pipe previously laid and driven home with a wooden caulking tool and mallet; when in position such yarn shall not occupy more than one quarter of 也 e depth of 也 e socket. The socket shall then be filled wi 也 a cement-
mortar fillet worked all round. The fillet shall be bevelled off and shall extend for a length of not less 也 an 50mm 企 om 也 e face of 也 e socket.

b) For "Ogee" pipes, the joints shall be thorou,拉 ly cle 組ed and
wetted, and cement-mortar shall be applied evenly to the ends so as to completely fill the joint. The pipes shall then be properly drawn toge 也 er and 也 e outside of the joint shall be neatly pointed.

c) Speci 祉 care shall be 個 ken to remove any excess mort位組 d to
clean each pipe by drawing a tight-fitting was 也 rough 白白 e work proceeds. The trenches and pipes shall be kept 企 ee 企 om water until 也 e JO 帥的也 orou 拉 ly set after which time the pipes shall be flushed 企 om end to end with water, and left clean and free 企 amobs 甘 uction.

d) For pipes with flexible join包 , 也 e pIpe m 組 ufae如 rer's
IDS 甘 ue 世 ons shall be closely followed. The joint shall be carried 也 rough to 也 e foundation so 也 at 也 e overall flexibility of the pipe line is m 到 n 包 ined.

e) For pipes wi 也 precast concrete collar-jo 恆的 , one half the length
of the collar shall be caulked onto 也 e pipe using a suitable collar support to hold the collar concentric wi 曲曲 e pipe. 1:3

PS-46

SPECIFICATION 'A' 一 PARTICULAR

cement mortar shall be used in caulking on the collar in layers not exceeding 40mm 扭曲 ickness wi 也 suitable tools. After the caulking is completed the joints shall be covered and kept moist for 也 ree days. The tongue-end of the pipe shall be slipped into the collar during 也 e la 抖 ng process 個 d 也 e annular ring poured or caulked wi 也 1:3 cement-mortar, taking care to make a smoo 血泊 ternal connec 世 on. This method of jointing shall be used on plain bu 位 ended pipes or on tongue-and-groove pipes.

。 F or pipes butt ended wi 也包 -situ collars, cement-mortar shall be
applied evenly to the ends of the pipes to be jointed. The pipes shall 由 en be properly drawn toge 也 er. Excess mortar shall be removed to make a smoo 也 external and intemal connection.

訟法的街 t or in-si ω collars shall be constructed 臼 shown on 也 e
Drawings.

7.16 Jointing Pipes of Different Materials

a) Ductile Iron to UPV C Joints

Where UPVC branch pipes connect into ductile iron droppers on 也 e flushi 且 gm 位叫 lation, speci 祉 cast iron fittings shall be used. These g 位 ings shall have flanged connections for coupling to the main and modified union connection on the branch with fibre-g 位 ket for connection to UPVC branches

b) Copper to Ductile Iron or Steel Joints

Where copper fl 組 ges join to C.!. or steel fittings, valves etc. of ferrous metal, special sleeves shall be inserted in over-drilled bolt holes to isolate direct contact to bolts and flanges. Sir 世 1 位紗 , 趾 ghs 甘 'ength fl 前 fibre washers to be used on bo 吐 1 ends of 也 e bolt between the steel washers and flanges to prevent direct dissimilar metal con 個 ct.

c) Galvanized Steel ω Cast Iron Drainage Pipe

Galv 位 rizoo to cast iron joints are to be made wi 也 hemp and caulked h 祉 , cold ca 叫組 ng compound "Philplug" PC3 or PC4, or an approved
jointing compound well rammed 恆的自 e socket.
d) UPVC to Cast Iron Draina ε e Pipe

PS-47

SPECIFICATION ‘ A' 一 PARTICULAR

UPVC to cast iron sockets or bossed connections shall be made with screwed joints or caulked cement and yam, cold ca 叫起 ng compound or approved j ointing compound.

7.17 Expansion Joints

a) Wherever possible, advantage shall be taken of changes in direction of pipes t 。但 ke up expa 且 sion and contrac 討 on due to tempera 仙 Ie changes of 也 e pIpe ∞ nten 臼 .

b) Expansion joinu弓 and movement joints shall be provided on
pipes across the building expansion joints and elsewhere to absorb 也 e effect of expansion on pipes as generally shown on the-: Drawings. Special attention shall be paid to provision of expansion joints on hot water pipework.

c) Where expansion joints are required, 也 ey shall be bellows type. Bellows shall be stainless steel with stele inner and outer telescopic sleeves. The joints shall have screwed ends and flanged joints for
Jom 包 of larger bore. The joints shall be suitable for a test pressure as specified for 也 e pipes. Each joint shall be suitable for a 仕 averse of not less 由組 25mm and if necessary a joint of larger diameter 也扭曲 e pipe shall be installed with reducing 宜 ttings ω ob 扭扭曲 e allowable required pipe movement.

d) Where movement points occur, couplings as Messrs. Viking Johnson or equivalent equal and approved shall be used so 由 at
building movement does not cause 企 ac 如 Ie of the pipework, etc.

e) Upon sizing and fixing expansion joints on pipes across the building exp 組 sion join 包 , 也 e Sub-Con 仕 actor shall take into account, in addition to the expansion/con 甘 'ac 世 on of pipes due to the tempera 側記 ch 缸 1ge 乳白 e effect of the relative horizontal movement between the 制 TO P 訂 ts of the building s 甘 ucture separated by the building expansion joint.

。 Expa且 sion coupling wi 也 neoprene seal ring at one end to be
used on UPVC piping.

g) On UPVC vertical/horizontal dr位 ..nagepIpe, ax! 祉 expansIon
coupling, as recommended by UPVC pipe/fitting manufacturer, to be supplied and installed as shown on the Drawings, of slip 可 pe WI 也 neoprene seal 也 19 be 趴 Teen 由 e two coupling members. Class and standard of expa 且 sion j oint to be the same 也 ose for pipes specified.

PS-48

SPECIFICATION ‘ A' 一 PARTICULAR

h) Where steel, c 路 t iron, or UPVC drainage pipes cross building expansIon J 0 旭包 , expansion joints, mainly for lateral movement
(as well 臼 for axial), of ei 也 er stainless steel bellows of n ω prene convolute design to be used.

i) Generally expansion bellows shall be installed mid way on each
water riser. Details and location of expansion joints shall be submitted to 也 e Surveyor for approval.

PS-49

SPECIFICATION ‘ A' 一 PARTICULAR


7.18 Pipe Guides


Pipe guides, are for use in long leng 也 S of pipe and ω be and 訂 'e to be fi 說 ed on each side of every joint to keep and to direct the movement of expansion and con 仕 action 企 om anchor points in 甘 ue ali 伊 ment in lateral direction towards the bellows or other flexible inserts shall take the form of enclosing hoops of mild steel flat to B.S.3974 : P 訂 t I, generally 40mm x 20mm in section. Such shall be secured to roller brackets and 0 白白血泊 ngs by me 扭扭
of bracket attachments. Metal guides for UPVC pipes shall be I 垣 ed internally wi 也 UPVC material slightly oversized to allow 位 ial movement of the pipe.


Generally, guides shall be fixed at points between the anchors and expansion joints to ensure 也 at 也 e 也 rust is line 位的也 e axis of 也 e pIpe.


7.19 Flexible Connection


a) On suction of all flush and 企 esh water pumps.


All stainless steel cons 甘 uction, double flanged, flexible hose, one for each pump, full line size, rate 7 BAR, working pressure, fully s 凶 table for sea water when used on flush water pumps. Minimum length between flanges to be 300mm.


b) On discharge of all pumps.


All stainless steel cons 甘 uction, externally braided, double flanged, flexible hoses, two for each pump, full line size, rate 17 BAR minimum working press 叮臥倒 ly suitable for sea water when used on flush water pumps. Minimum length between flanges - 300mm.


7.20 Strainer


Strainer shall be Y pa: 吐 em bronze body for potable water system and gunmetal body for flush water system wi 也 screwed connection up t, 。中 65mm and cast iron body flanged for 中 80mm and over, wi 也 removable mesh s.s. baskets and of such design as to permit blowing out of accumulated dirt without discontinuity of service. Strainer shall be provided as spec 也 ed and shown on the Drawing.

[ Next Thread | Previous Thread | Next Message | Previous Message ]

Replies:

[ Contact Forum Admin ]

Forum timezone: GMT-8
VF Version: 3.00b, ConfDB:
Before posting please read our privacy policy.
VoyForums(tm) is a Free Service from Voyager Info-Systems.
Copyright © 1998-2019 Voyager Info-Systems. All Rights Reserved.