STATEMENT OF GROUNDING SYSTEM INSTALLATION.doc

method statementproject name: intercontinental resort & spa da nangmep package 3project ref: cna-hte/2800ref : dnic-pkg3/csf-ms/e/0002/adate : 11 jan 2011 rev : 00method of statement for grounding & lightning system installation/ bin php thi cng h thng tip a v chng st.1. aim/ mc tiu:to describe electrical works associated with installation of grounding system / lightning protection system. nhm m t cng tc in lin quan ti lp t h thng ni t v chng st.the grounding system / lightning protection system are designed to ensure the complete safety of both persons and equipments throughout the airport terminal and all associated building and facilities.h thng ni t/chng st c thit k nhm bo m s an ton cho c con ngi v thit b tt c ta nh v phng tin lin quan.due to bs-6651 for lightning protection standard, required earth resistance lightning directly below 10 theo tiu chun bs-6651 v h thng chng st yu cu in tr ni t h thng chng st trc tip di 10 .2. scope of works/ phm vi cng vic:this method statement covers works as shop drawing indicated and schedule. bin php thi cng ny bao gm nhng cng vic theo nh tin v bn v thi cng ch r.3. references/ tham kho:o specification/ ct tnh k thut: (km ti liu trnh mu)? chapter?o shop drawings/ bn v thi cngo bs-6651 standard/ tiu chun bs-6651 ?o phn mm tnh ton h thng tip t ca loresco-m/calculators.html?o van ng th ca lpi- c?.au/lpiproducts/earthingandbonding.aspx4. optimal design to reduce power back land/ti u thit k nhm gim in tr to original lightning position design of the roof will not change. from the air terminal position on the roof to escape lightning ground wire connected to each copper earth rod separately.phn trn mi s gia nguyn thit k ban u. t cc v tr kim thu st trn mi nh i dy thot st xung t ni vi tng cc ring l.o connected copper grouding rods in to the ground network by bare copper cable m50tin hnh kt ni cc cc li bng cp ng trn m50 thnh mt h thng chung.o changes to copper bonded grounding rod to pure copper grounding rodthay i cc tip t t loi cc m ng sang loi cc ng nguyn cht.o the buildings have four grounding rods 16 (br, hp, s4, bs), 3 meters long will bed added more rods to reach earth resistance lightning below 10 . the distance between 2 rods 2 times the length of rod and enhancing put chemical for the trench 5 package/building(1 pack = 22.7 kg).nhng nh c thit k ng 4 cc tip a 16 (br, hp, s4, bs), di 3m s c ng thm cc t in tr t nh hn 10 . khong cch gia hai cc 2 ln chiu di cc v tng cng ha cht rnh mi nh 5 bao (1 bao = 22,7 k).o the building have 6 to 8 grounding rods 16 (ar, cf, rb, sr), 3 meters long will bed added more 6 rods 16, length 3m. the distance between 2 rods 2 times the length of rod and enhancing put chemical for the trench 7 package/building(1 pack= 22.7 kg).mt s nh hin ang ng 6 n 8 cc tip a 16 (ar, cf, rb, sr), di 3m s c ng thm 6 cc tip a 16, di 3m. khong cch gia hai cc 2 ln chiu di cc v tng cng ha cht rnh mi nh 7 bao (1 bao = 22,7 k).o the buildings are located closely as the ar-br-s41 and sr, bs, br can be linked together by m50 bare copper wire to reduce the earth resistance of the whole system down. to prevent the occurrence of voltage difference in the area of land next to areas where they can use equipotential clamps to linking the two systems to eliminate this voltage difference.nhng nh c v tr gn nhau nh ar-br-s41 v sr, bs br c th lin kt cc nh li vi nhau nhm gim in tr ni t ca c h thng xung thp. ngn nga vic xut hin s chnh lch in p trong khu vc tip t i vi khu vc ni chung c th s dng van ng th (equipotential clamps) lin kt hai h thng nhm loi b s chnh lch in p ny5. sequence of works/ tun t cng vic:5.1 material and equipment/ vt t v thit b:1) copper earth rods/ thanh ci ni t bng ng.2) bare copper cable/ cp ng trn.3) cable clamp for earth rod and copper cable/ kp dy cp cho thanh ci ni t v cp ng.4) copper tape and clips/ bng keo v kp bng ng.5) pvc pipe/ ng pvc.6) concrete grounding pit/ h b tng.7) cable lugs/ u ct.8) air terminal/ kim thu st9) earth bar with disconnecting link/ thanh ci ni t km mi lin kt ngt10) furse weld/ mi hn.11) earth tester/ dng c kim tra ni t.12) welding machine/ my hn.13) welding rod/ que hn.14) field tester/ dng c th ti cng trng.5.2 type of connection/ phng php kt ni: o connect earth rod to bare copper wire ( detail-1 ).kt ni thanh ci ni t vo dy ng trn. (bn v chi tit-1)o connect rebar to bare copper wire (detail-2).kt ni thanh ct thp vo dy ng trn (bn v chi tit-2)o connect copper bar to bar copper wire ( detail-3 ).kt ni thanh ng vo dy ng trn. (bn v chi tit-3).o connect cable trays/ladders and pipes to grounding system (detail of electric continuity for cable tray shall be provided in method statement for trays/ladders installation.).ni mng cp/ thang cp v ng cp vo h thng ni t (bn v chi tit tnh lin tc cho mng cp c cung cp trong bin php thi cng lp t mng cp/ thang cp).5.3 procedure of installation of grounding system/ quy trnh lp t h thng ni t: 5.3.1 installation of exothermic welding system/ lp t h thng hn nhit:the mould crucible with suitable size shall be used for exothermic welding.khun nung vi kch thc ph hp s c s dng cho hn nhit.a) the following procedures shall be followed before conduct the exothermic welding. quy trnh sau s c theo di trc khi tin hnh hn nhit.i) ensure that the mould is always clean and free of moisture.bo m rng khun lun sch v khng mii) ensure that the tap hole is always in well-defined condition.bo m rng l bt trong tnh trng c xc nh.iii) ensure that the correctness of connection selector.bo m tnh chnh xc ca b chn la u ni.iv) ensure that the correctness of welding powderbo m tnh chnh xc ca bt hn.b) procedure to conduct the exothermic connections.quy trnh tin hnh mi ni ta nhiti) fix the connection selector to the handle clamp as per the require sizes of conductor to be welded.gn b chn la u ni vi cht iu khin nh trn kch thc yu cu ca dy dn hn.ii) place the conductor in the mould, ensure that connection selector is used in accordance to the conductor to be welded.t dy dn trong khun, bo m b chn la u ni c s dng tng ng vi dy dn hn.iii) close the handle clamp and lock in the lock position, drop the metal retaining disc into the bottom of the mould crucible. ensure that the metal retaining disc is correctly, completely seated and cover up the tap hole.ng cht iu khin v kha cht li, h bn gi kim loi gn vo y khun nung. bo m rng bn gi kim loi cha ng, v ph l bt.iv) deposit the welding power into the crucible and spread a little amount on top of the mould edge as a role of starting power.ph bt hn ln ni nung v phn tn mt t trn nh ca g khun khi in nng bt u hot ng.v) close the mould lips, and ignite with the flint gun.ng ming khun, v bt vi phun la.vi) open the mould after a few seconds where the reaction is completed or the metal has been solidified.m khun sau vi giy lc phn ng hon thnh hoc kim loi rn li.vii) do not touch the welding surface after the reaction.khng nn tip xc vi b mt hn sau phn ng.viii) clean up the mould for the next joint.lm sch khun cho mi hn k tip.5.3.2 earthing cable installation/ lp t cp ni t:a) the earthing conductor, bare copper cable shall be installed as per approved shop drawing.dy ni t, cp ng trn s c lp t theo nh bn v thi cng duyt.b) ensure that the copper cable is straight (not wavy) so that it fits nicely into the exothermic mould prior to the exothermic welding.bo m rng cp ng thng (khng b un cong) n khp vi khun ta nhit trc khi hn nhit.c) ensure that the copper cable is free of dirt / oil and dry keeping.bo m rng cp ng khng b bn/ khng b dnh du v kh thong.5.3.3 earth rod installation/ lp t thanh ci ni t:o the copper rod is to be driven into the ground by means hammer drill / sledge hammer.thanh ci ng c ng xuyn qua t bng ba khoan/ba t.o make sure the rods are coupled with coupling and driving studs before hammering as it will protect the thread or the head of the rods from damaged.bo m cc thanh ci c ghp km vi cht ni v cht ng trc khi ng v n s bo v mi ni hoc u thanh ci trnh b h hng.o after the desired depth has achieved, the earthing conductor will be joint to the earth bar / rod clamp of the earth pit and fastened it securely.sau khi t ti su mong mun, dy tip t s c gn vi thanh ci ni t/ b kp thanh ci ca h t v sit cho tht cht.o resistivity check should be taken and if the resistivity is not achieved to required value then it is advisable to drive it deeper.nn kim tra in tr v nu in tr khng t c ch s nh yu cu th nn ng su hn.o the rod shall be driven as deep as possible and do not force to drive it as it may break the coupler and loose the rod.thanh ci s c ng cng su cng tt v khng ng p ln cc v iu ny c th lm h b ni v lm lng thanh ci.o the number of rods driven into the ground will be dependable to the soil resistivity on that particular area and as per approved shop drawing.s thanh ci ng tip t s ph thuc vo in tr t trn vng t chuyn bit v nh trn bn v thi cng duyt.5.3.4 earth pit/ h t:a) install the inspection pit and ensure that it is flush with the external ground / road level. lp t h kim tra/ quan st v bo m rng n bng vi phn t v mt ng bn ngoib) ensure that the earth pit is free from dirt and rubbish. bo m rng h t sch s v khng c rc.5.4 safety control method/ bin php qun l an ton:a) general/ tng quan:the safety procedure generally have to be applied for all engineers, supervisors, workers as following bellow:cc quy trnh/ th tc an ton phi c p dng cho tt c k s, gim st vin, cng nhn nh sau:o make sure that all personal protection equipment (ppe) be provided on site before starting work such as helmet, safety boot, safety glasses, glove, mask etc.chc chn rng tt c trang thit b bo h c nhn c cung cp ti hin trng trc khi bt u cng vic nh: nn bo h, ng an ton, knh an ton, gng tay, mt n, v.vo make sure that ppe must be wear in the correctly way when working.chc chn rng nhng trang thit b bo h c nhn phi c mc ng cch khi lm vic.o tools and equipments shall be inspected by authorized person before carried out the work.cng c v thit b s c ngi c thm quyn kim tra trc khi thc hin cng vic.o barricades and sign posts for warning shall be provided on site.lp ro chn v bin cnh bo ti cng trng.o fire extinguishers shall be provided on site wherever exothermic welding works and always ready to use.trang b bnh cu ha ti hin trng hay bt c ni no thi cng hn nhit v sn sng s dng.b) working with welding machine and exothermic welding/ lm vic vi my hn v hn nhit:o ensure worker wear safety glasses, gloves, helmet etc.bo m cng nhn eo knh an ton, gng tay, m bo h, v.vo fire extinguisher shall be always ready at work placebnh cu ha lun lun c sn ni lm vic.o welding machine must be checked carefully before using. my hn phi c kim tra cn thn trc khi s dng.o welder must be qualified and skill.th hn phi c chuyn mn v k nng.c) working at height/ lm vic trn cao:o ensure every worker wear safety harness when working at more than 2 m height.bo m rng cng nhn eo ai an ton khi lm vic cao trn 2m.o safety protected handrail on top layer of scaffolding shall be provided.lp lan can an ton trn tng nh ca gin gio .o ensure a ladders are in good condition/quality.bo m thang ch a trong tnh trng, cht lng tt.5.5 material storage/ kho cha vt t:a) storage of exothermic welding materials should be in a clean, dry, “no smoking” area and should be restricted to access by authorized personnel only. kho vt t hn nhit nn trong khu vc sch, kh, khu vc “cm ht thuc” v nn c ngi c thm quyn kim sot nghim ngt.b) storage condition shall be such that exothermic welding materials are not subject to rough handling or physical damage. storage shall be in cool place and in condition no humidity and moisture. iu kin bo qun cho cc lai nh vt liu hng nhit khng ty thuc h hng vt l hoc qun l khng tt. kho vt t phi t ni thong mt v trong tnh trng khng c mc) all boxes or container of material should be stored in accordance with container (carton) or label marking “this side up”tt c hp v container vt t s c lu tr theo container (hay thng carton) v dn nhn “mt trn”d) these materials must be stored under shelter to protect the boxes from the elements and raised to protect them from dampness or wet surface.nhng vt t ny s c bo qun ni c mi che bo v thng carton v tng cng bo v vt t khi m t.5.6 grounding connection/ ni t:detail-1/ bn v chi tit-1:o connect earth rod to bare copper wire.k ni thanh ci ni t vi dy ng trn.hn nhitdy ng trn 95sqmmthanh ci ni t m20 x 3000lfurseweld connection detail/ bn v chi tit mi hndetail-2/ bn v chi tit-2:o connect rebar to bare copper wire: kt ni thanh ct thp vi dy ng trnfurseweld kt nidy ng trnthanh ct thp dia 32mmdetail-3/ bn v chi tit-3:5.7 execution work for earthing of lightning protection/ cng tc thi cng h thng ni t & chng st:o drive the earth rods into the earth by hammer.ng thanh ci ni t vo t bng ba.o excavate a trench (dxw: 800:500) to link earth rods together by soft drawn bare copper wire .o mng cp (su: 800, rng: 500mm) ni thanh ci ni t vi nhau bng dy ng trn mm.o link earth rods to grounding network.kt ni thanh ci ni t vo h thng ni t.o backfilling the trench.lp mng cpo testing and record earthing resistant value.kim tra v ghi li kh nng chu bn ca ni to joints shall be protected against rust by cold galvanized paint.b ni s c bo v bng sn trng km ngui.o contact surfaces shall be flush prior to jointing.b mt tip xc s c lm phng trc ri kt ni.o bolt connections of copper wire with hot dip galvanized steel bar and copper wire with copper bar should reach mechanical effect and electrical effect.bu-lng ca dy ng vi thanh thp nung v dy ng km thanh ng nn t hiu ng c in. o during the driving of the rods into the earth, it is better to measure value of the resistance to earth in order to quantity of necessary grounding rod. sut qu trnh ng cc thanh ci vo t, tt hn l nn o sc chu bn ca t s dng thanh ci ni t cn thit.5.8 x l ha cht gim in tr t/handling of chemicals to reduce soil resistivity:o prepare wiring trenchchun b rnh i dyo ensure no garbage on the trenchm bo rnh sch khng c rco put the chemicals along the track covers a thick layer of copper 3mm ha cht dc rnh bao ph ln cp ng 1 lp dy 3mmo backfilling the trench.tin hnh lp t hon tr mt bng.5.9 procedure of installation of lightning protection system/ quy trnh ca vic lp t h thng chng st:o the installation of the lightning arresters will be closely coordinated with apron floodlight and roofing works.vic lp t kim thu st s phi hp vi vic lp mi v lp n c chp cn quang.o the grounding system for lightning protection system must be established prior to install lightning protection system ( refer to item 4.4 for grounding installation ).h thng ni t cho h thng chng st phi c thit lp trc khi lp t h thng chng st (tham kho mc 4.4 v lp t ni t).o the down-conductor shall not be isolated nor enclosed in pvc pipe and placed internal in the apron lighting towers.dy dn i xuyn tng s khng tch bit cng nh bao quanh ng pvc v t bn trong thp chiu sng c chp cn quango the down conductor should be fixed with a test joint in a position that is convenient for the tests but shall not be reached by irresponsible persons.dy dn i xuyn tng s c gn km hp ni kim tra ti v tr thun tin v ch dnh cho nhng ngi c phn s.o the down conductor 95mm2 bare copper wire shall be connected directly to the mounting base of the lightning arrester by terminal lug.dy dn bng ng trn i xuyn tng dy 95mm2 s ni trc tip vi b lp rp kim thu st bng u ct.o the lightning arrester should be fitted into the mounting base before lifting them and connecting to the apron floodlight mast.kim thu st s c gn vo b lp rp trc khi nng ln v kt ni vi nhauo after completing the installation of lightning arrester into the apron floodlight mast, it shall ensure that the down conduct