1、Installation of Electrical Equipment in Hazardous AreasDenial of Ignition Sources to flammable Gases It cannot be stressed how important the philosophies followed to deny ignition sources to flammable gases are.The smallest ignition source can lead to the most dire consequences,Both far away Deepwat
2、er Horizon,Gulf of Mexico,April 2010And close to home-Pingyu Coal&Electric Co Ltd,Yuzhou,Henan Province,October 2010This presentation is based on the International Elecrotechnical Commissions publication IEC-60079There are other publications such as the National Electric Code(NEC)in the USA that hav
3、e also produced standards for hazardous areas but the equipment in this project will be to IEC standardsThe IEC has over a century of experience producing electrical standards The first hazardous area standards were created for the mining industry and then expanded to include the oil and gas sector
4、IEC standards are not frozen in time but evolve for many reasons such as new materials being produced,technical advances are made and findings from disaster enquires to name but a few These standards are written to provide the best possible protection in the event of a gas escape utilising experienc
5、e of prior disasters and the leading experts in the hazardous area field Flammable gases require ONLY ONE source of ignitionAll equipment MUST comply with the regulationsDisaster news stories usually say there was AN explosionAll regulations MUST be adhered to=There can be no exceptionsThe zones for
6、 this vessel can be found on drawing M40188-1030015-Hazardous Area PlanPlus-all equipment in exterior locations which is capable of operation after a shutdown is to be suitable for installation in Zone 2 locationsThere are various philosophies that are defined by the IEC to deny source of ignitionNo
7、te;There is a philosophy hierarchy,Zone 0 equipment can be used in Zones 1&2,Zone 1 equipment can be used in Zone 2 List of Hazardous Areas on Hai Yang Shi You 981Bell nipple zone 1Shale shakers-zone 1Heli fuel area-zone 1Battery locker-zone 1Paint locker-zone 1Below heli deck-zone 1Crown zone 1Mud
8、pits-zone 2Drill floor-zone 2Riser storage-zone 2Vents from enclosed hazardous areas zone 2Loading stations port and starboard zone 2all equipment in exterior locations which is capable of operation after a shutdown is to be suitable for installation in Zone 2 locations.Tips on inspection of Ex equi
9、pment;(A full checklist is provided in the handout)Equipment is correct for ZoneAll cables must be armouredGlands for Exd should be Exd or ExdeGlands for Exe should be Exe or ExdeArmour to be clamped by the glandFor Ex equipment blanks to be Ex ratedFor Exe equipment the glands and blanks thread len
10、gth should be minimum 6mm or IP washer and internal lockout When earth ring is used,this must be located between gland shoulder and IP washer Exd,Exe equipment earth wire should be minimum 2.5mm2 up to 16mm2 power conductor Exi equipment earth wire should be minimum 4mm2 All terminations should only
11、 have one conductor per terminal All terminations should be correct and tight Wire insulation should be maintain right up to the metal of the terminal Crimping tools of the hand rachet type must be used All spare conductors must be terminated both ends Insulation resistance test to be carried outEqu
12、ipment is Incorrect for zoneUncertified for zoneCorrect certificationCorrect glands and installed to manufacturers instructionsAs above gland incorrectly installedCorrect size of glandUse of tapeBlank plug uncertifiedUncertified blankBlank plug to be certified and correctly installedExe locknut requ
13、iredIncorrect use of earth ringCorrect use of earth ringTwo cores one terminalCorrect connection of two cores into one terminalIncorrect terminationTerminal rail to be fixed and free from vibrationExposed conductorsSpare conductors to be terminatedCable supportIncorrect use of toolsEquipment is labe
14、led correctlyLabel to include;a)The name of the manufacturer or his registered trademarkb)The manufacturers type identificationc)The symbol Exd)The symbol for each type of protection usede)The symbol of the gas group for that equipmentf)For group II electrical equipment,the symbol for the temperatur
15、e classg)A serial number except for small equipment and accessories All the above photos are indeed from our rig the Hai Yang Shi You 981.It is very important for everyone involved in installations in hazardous areas to have knowledge of the dangers and consequences that one simple mistake or compromise for schedule can soon become a disaster.
