耐火(huo)(huo)性能(neng)(neng)(neng)是指(zhi)母(mu)(mu)(mu)线槽(cao)除了必须(xu)具(ju)有(you)阻燃性能(neng)(neng)(neng)和防火(huo)(huo)性能(neng)(neng)(neng)外，还要(yao)求母(mu)(mu)(mu)线槽(cao)在火(huo)(huo)灾(zai)时能(neng)(neng)(neng)够维持(chi)电(dian)路(lu)(lu)的完(wan)整(zheng)性。GB7251.2-2006没有(you)对(dui)耐火(huo)(huo)试验(yan)(yan)项(xiang)目提出(chu)要(yao)求。GA/T537-2005要(yao)求母(mu)(mu)(mu)线干线系统（母(mu)(mu)(mu)线槽(cao)）耐火(huo)(huo)性能(neng)(neng)(neng)试验(yan)(yan)应同时进行喷淋(lin)试验(yan)(yan)和耐火(huo)(huo)性能(neng)(neng)(neng)验(yan)(yan)证(zheng)，两项(xiang)试验(yan)(yan)均合(he)格(ge)方可(ke)判定其耐火(huo)(huo)性能(neng)(neng)(neng)合(he)格(ge)。这是因为火(huo)(huo)灾(zai)发生(sheng)时，耐火(huo)(huo)母(mu)(mu)(mu)线槽(cao)应能(neng)(neng)(neng)承受消防龙头救(jiu)火(huo)(huo)喷水的冲(chong)击，不应发生(sheng)母(mu)(mu)(mu)线间的短路(lu)(lu)，电(dian)路(lu)(lu)供电(dian)不应中断，即耐火(huo)(huo)母(mu)(mu)(mu)线槽(cao)的外壳防护等级要(yao)达到IP6X级别(bie)。
GA/T537-2005附录(lu)A规定(ding)了喷淋试(shi)验(yan)(yan)(yan)方法，包(bao)括试(shi)验(yan)(yan)(yan)装(zhuang)置、试(shi)验(yan)(yan)(yan)条件、试(shi)验(yan)(yan)(yan)要求、安装(zhuang)、试(shi)验(yan)(yan)(yan)程(cheng)序和(he)判(pan)定(ding)条件。试(shi)验(yan)(yan)(yan)应(ying)在(zai)一个合适的箱(xiang)体(ti)（或试(shi)验(yan)(yan)(yan)室）内进(jin)行，该箱(xiang)体(ti)（或试(shi)验(yan)(yan)(yan)室）应(ying)具(ju)有(you)处理燃(ran)烧产生的任何有(you)害气(qi)体(ti)的设施，并有(you)足(zu)够的通风来维(wei)持试(shi)验(yan)(yan)(yan)过程(cheng)中的火焰(yan)，箱(xiang)体(ti)（或试(shi)验(yan)(yan)(yan)室）外(wai)部环境温度应(ying)保证在(zai)5~40℃之(zhi)间，喷淋试(shi)验(yan)(yan)(yan)后，保持电压，即没有(you)一个熔(rong)断(duan)器或断(duan)路器断(duan)开，导(dao)体(ti)不断(duan)，即灯(deng)泡一个也不熄灭，则表明线路未丧失完(wan)整性(xing)，试(shi)件喷淋试(shi)验(yan)(yan)(yan)合格。
耐火(huo)(huo)性能试(shi)(shi)(shi)验(yan)中的(de)(de)试(shi)(shi)(shi)验(yan)装置、试(shi)(shi)(shi)验(yan)条件(jian)(jian)、测量与观察(cha)，GA/T537-2005基(ji)本引用GB/T9978一(yi)1999的(de)(de)相关(guan)要(yao)求，但对于(yu)(yu)受(shou)火(huo)(huo)条件(jian)(jian)、试(shi)(shi)(shi)件(jian)(jian)要(yao)求、安(an)装、试(shi)(shi)(shi)验(yan)程序和判(pan)定条件(jian)(jian)，GA/T537-2005做出了详(xiang)细的(de)(de)规定，如要(yao)求试(shi)(shi)(shi)件(jian)(jian)为四面受(shou)火(huo)(huo)（实际工(gong)程有特(te)殊(shu)要(yao)求的(de)(de)除外），试(shi)(shi)(shi)件(jian)(jian)为三相四线(xian)制或三相五线(xian)制直线(xian)型母线(xian)干(gan)线(xian)耐火(huo)(huo)单(dan)元，受(shou)火(huo)(huo)段长度(du)至少为4m，并(bing)(bing)含有一(yi)个接(jie)(jie)头(tou)。试(shi)(shi)(shi)件(jian)(jian)安(an)装时，试(shi)(shi)(shi)件(jian)(jian)两(liang)(liang)端(duan)支承在(zai)耐火(huo)(huo)试(shi)(shi)(shi)验(yan)炉炉壁上，两(liang)(liang)端(duan)伸出试(shi)(shi)(shi)验(yan)炉长度(du)均(jun)不小于(yu)(yu)500mm并(bing)(bing)用不燃性隔热材料封堵两(liang)(liang)端(duan)；应(ying)使试(shi)(shi)(shi)件(jian)(jian)接(jie)(jie)头(tou)处(chu)在(zai)炉中间，在(zai)接(jie)(jie)头(tou)两(liang)(liang)侧各(ge)设置一(yi)个支撑(cheng)，并(bing)(bing)保持其间距不小于(yu)(yu)1000mm，该支撑(cheng)由试(shi)(shi)(shi)验(yan)单(dan)位统一(yi)提供，并(bing)(bing)使炉顶距试(shi)(shi)(shi)件(jian)(jian)的(de)(de)距离(li)不小于(yu)(yu)150mm；为了检验(yan)试(shi)(shi)(shi)件(jian)(jian)线(xian)路的(de)(de)完整性，应(ying)进行必要(yao)的(de)(de)电气(qi)连接(jie)(jie)。
联系我们