之前在我的文章中提到了各种水喷淋灭火系统, 不少朋友对这几个系统感到很困惑, 现在对它们 进行详细的解释。它们分别是:
1.
Water Spray System (Deluge system)
2.
Water Sprinkler Systems
3.
Water Mist Systems
这几个系统有一个共性, 它们都是固定灭火系统, 都是采用喷水的方式进行灭火。 但是它们依然 有各自的特点。
先介绍一下 water spray system,它相对于其他两个系统来讲, 最大的区别在于这个系统要
由人工 启动,开放式喷嘴(也就是说平时的时候喷嘴里面是没有水的) 。主要用于露天危(wei)险区域保护。 它通常也叫 deluge system,deluge 的英文意思是洪水, 浸没。 从字面上的意思就是用大量的水一 直对失火区域进行喷淋, 以冷却的方式灭火, 这一来我们现在就很显然知道为什么它主要用于露 天区域灭火。否则,舱室里面排水可能来不及。既然是大量的水,就需要源源不断的水源,这也 就这个系统需要用海水作为灭火剂的原因。
系统由海水供给泵, deluge 阀,管路,喷嘴,组成。在海洋平台设计中,海水供给泵直接就可以 用海水消防泵,也就是说, deluge 高中英语作文范文system 实际上是作为消防系统的分支管路,与消防栓不同的 是,这里是用的 deluge 阀和喷嘴。
Deluge 人际关系系统的喷嘴,对形成的水滴相对很大,下图就是典型的灭火效果。
deluge 阀,事实上是一个减压阀,通过电磁阀控制 deluge 阀的开关,来控制是否喷水。
这个系统在钻井平台上主要用于一下几个区域的灭火, 直升机加油站区域, 测井区域, 节流压井 管汇区域,整个钻台区域。
MODU ,USCG ,FSS ,NFPA 这几个规范有对系统设计的要求,摘录几条重要的:
1.
A fixed water spray system is to be installed for the process equipment.
The intent of the water spray system is to keep the process equipment cool and reduce the risk ofescalation of a fire. Water spray systems are to be capable of beingactuated both automatically by a fire detection system and manually.Installations are generally to be in accordance with NFPA Standard 15,or other equivalent standard such as API RP 2030. Deluge isolationvalves are to be located in a safe area and outside the fire zone theyprotect.
2.
Procesquipment, including hydrocarbon vesls, heat exchangers, firedheaters and other hydrocarbon handling systems, are to be protectedwith a water spray system. The system is to be 骂人英语designed to provide awater density of 10.2 liters/老师的由来min/m2 (0.25 gpm/ft2) of
expod surfacearea for 可爱漫画图片uninsulated vesls, or 6.1 liters/min/m2 (0. 15 gpm/ft2) ofexpod surface area for insulated vesls. Process equipment supportstructure, including saddles, skirt, legs, but not condary deckstructural members, is to 记载的读音be protected with a water spray systemdesigned to provide a water density of 4.1 liters/min/m2 (0. 10gpm/ft2).
Alternatively,the u of intumescent coatings may be acceptable in protecting thesupport structure, provided the lection of the fire rating of thecoating is bad on the results from a risk analysis and/or fire loadcalculation which must be reviewed and accepted by ABS. The condition(intactness) of the coatings will be the subject of surveyor inspectionduring attendance of the unit following normal survey intervals. Forgas-handling equipment, such as gas compressor skids, where thehydrocarbon liquid inventory is kept minimal, a water spray system isnot required if the equipment is provided with an automatic blowdownupon the process shutdown.登飞来峰拼音版
3.
Wellheadswith maximum shut-in tubing pressures exceeding 42 kg/cm2 (600 psi) areto be protected with 生活的邀请函a water spray system. The water spray system is tobe designed to provide a minimum water density of 20.4 liters/min/m2(0.50 gpm/ft2) bad on the protection of wellheads, ESD valves, andcritical structural components including the firewall.
第二个, water sprinkler system,其实全称应该叫做 accommodation sprinkler system。看这个名称 就知道的用途了, 很显然用于钻井平台生活区灭火。 如果细心的话, 这个与普通写字楼里面的水 雾灭火系统相似, 抬头看看天花板, 在天花板中间可以看到不少均匀分布的小喷嘴。 喷嘴里面有 玻璃的感应器,一旦破裂,水就自动喷射出来。
显然, sprinkler system 的喷嘴是封闭式的,管路平时需要保持,承受一定的压力。这就需要整个 系统有蓄能器之类的保压装置。 由于用于生活区房间, 楼梯间的灭火保护, 我们需要的灭火介质 是淡水,而海水仅仅只是作为备用的应急水源。
系统由 sprinkler 控制站,管路,喷嘴,监测报警组成。这个系统比较简单,不做过多描述。 一些要求:
1.
Forexisting fixed installations where passive protection requirements arenot fully met,
the accommodation spaces are to be protected by anautomatic wet pipe sprinkler system supplied from the firewater system.Design of the system is to be bad on NFPA Standard 13 requirementsfor light hazard occupancies, or other acceptable standards such asChapter II-2, Regulations 12 of SOLAS 1974 and Amendments.
Freshwater is normally to be provided to fill the sprinkler piping. However,the system may be charged with awater if precautions are taken toeliminate diment and marine growth in the system.
2.
SVR4-7-3/9.5 requires sprinklers to be placed in an overhead position andspaced in a suitable pattern to maintain an average application rate ofnot less than 5 L/min/m2 (0. 12 gpm/ft2) over the nominal area (i.e.,gross, horizontal projection of the area to be covered) covered by thesprinklers. However, the u of sprinklers providing an alternativeamount of water suitably distributed so as to be not less effective maybe considered.