一、爆破片概(gai)述
爆(bao)破(po)(po)片的作(zuo)用是在(zai)設備(bei)或(huo)(huo)管道壓力突然升(sheng)高(gao)尚(shang)未引起(qi)爆(bao)炸前，由(you)于(yu)爆(bao)破(po)(po)片兩(liang)側壓力差達到(dao)預定(ding)溫(wen)度下的預定(ding)值(zhi)時，即(ji)先(xian)行破(po)(po)裂，排(pai)出設備(bei)或(huo)(huo)管道內的高(gao)壓介質(zhi)。因此爆(bao)破(po)(po)片是防止設備(bei)或(huo)(huo)管道破(po)(po)裂的一(yi)種安(an)全(quan)泄放裝置(zhi)(zhi)。爆(bao)破(po)(po)片安(an)全(quan)裝置(zhi)(zhi)具有結構簡單、靈敏、準確、無泄漏、泄放能力強等優點(dian)。能夠(gou)在(zai)黏(nian)稠、高(gao)溫(wen)、低溫(wen)、腐蝕(shi)的環境下可靠地工作(zuo)，還(huan)是超高(gao)壓容器的理想安(an)全(quan)裝置(zhi)(zhi)。
爆破片典型圖(tu)(tu)見圖(tu)(tu)6.3.24。
二、爆(bao)破片的分(fen)類
按(an)照結構(gou)型(xing)(xing)(xing)式(shi)來分(fen)類，爆(bao)(bao)(bao)(bao)破(po)片(pian)(pian)(pian)(pian)(pian)(pian)主(zhu)要有三(san)種，即平板(ban)型(xing)(xing)(xing)、正(zheng)拱(gong)(gong)(gong)型(xing)(xing)(xing)和(he)反(fan)(fan)拱(gong)(gong)(gong)型(xing)(xing)(xing)。平板(ban)型(xing)(xing)(xing)爆(bao)(bao)(bao)(bao)破(po)片(pian)(pian)(pian)(pian)(pian)(pian)的(de)(de)(de)(de)綜合性能較(jiao)差，主(zhu)要用(yong)(yong)于(yu)(yu)低(di)壓(ya)和(he)超(chao)低(di)壓(ya)工況(kuang)，尤其(qi)是大型(xing)(xing)(xing)料倉(cang)。正(zheng)拱(gong)(gong)(gong)型(xing)(xing)(xing)和(he)反(fan)(fan)拱(gong)(gong)(gong)型(xing)(xing)(xing)的(de)(de)(de)(de)應用(yong)(yong)場合較(jiao)多。對于(yu)(yu)傳(chuan)統(tong)的(de)(de)(de)(de)正(zheng)拱(gong)(gong)(gong)型(xing)(xing)(xing)爆(bao)(bao)(bao)(bao)破(po)片(pian)(pian)(pian)(pian)(pian)(pian)，其(qi)工作原(yuan)理是利用(yong)(yong)材料的(de)(de)(de)(de)拉伸強度來控(kong)制爆(bao)(bao)(bao)(bao)破(po)壓(ya)力，爆(bao)(bao)(bao)(bao)破(po)片(pian)(pian)(pian)(pian)(pian)(pian)的(de)(de)(de)(de)拱(gong)(gong)(gong)出(chu)方向(xiang)(xiang)與壓(ya)力作用(yong)(yong)方向(xiang)(xiang)一致(zhi)。在使用(yong)(yong)中發現，所有的(de)(de)(de)(de)正(zheng)拱(gong)(gong)(gong)型(xing)(xing)(xing)爆(bao)(bao)(bao)(bao)破(po)片(pian)(pian)(pian)(pian)(pian)(pian)都存(cun)在相同的(de)(de)(de)(de)局限：爆(bao)(bao)(bao)(bao)破(po)時，爆(bao)(bao)(bao)(bao)破(po)片(pian)(pian)(pian)(pian)(pian)(pian)碎(sui)片(pian)(pian)(pian)(pian)(pian)(pian)會進入泄放管(guan)道(dao)；由于(yu)(yu)爆(bao)(bao)(bao)(bao)破(po)片(pian)(pian)(pian)(pian)(pian)(pian)的(de)(de)(de)(de)中心厚度被有意減弱，易(yi)于(yu)(yu)因疲(pi)勞而提前爆(bao)(bao)(bao)(bao)破(po)；操作壓(ya)力不(bu)能超(chao)過爆(bao)(bao)(bao)(bao)破(po)片(pian)(pian)(pian)(pian)(pian)(pian)最(zui)小(xiao)爆(bao)(bao)(bao)(bao)破(po)壓(ya)力的(de)(de)(de)(de)65％，由此(ci)導(dao)致(zhi)了反(fan)(fan)拱(gong)(gong)(gong)型(xing)(xing)(xing)爆(bao)(bao)(bao)(bao)破(po)片(pian)(pian)(pian)(pian)(pian)(pian)的(de)(de)(de)(de)出(chu)現。這(zhe)種爆(bao)(bao)(bao)(bao)破(po)片(pian)(pian)(pian)(pian)(pian)(pian)利用(yong)(yong)材料的(de)(de)(de)(de)抗壓(ya)強度來控(kong)制其(qi)爆(bao)(bao)(bao)(bao)破(po)壓(ya)力，較(jiao)之傳(chuan)統(tong)的(de)(de)(de)(de)正(zheng)拱(gong)(gong)(gong)型(xing)(xing)(xing)爆(bao)(bao)(bao)(bao)破(po)片(pian)(pian)(pian)(pian)(pian)(pian)，其(qi)具有抗疲(pi)勞性能優良、爆(bao)(bao)(bao)(bao)破(po)時不(bu)產生碎(sui)片(pian)(pian)(pian)(pian)(pian)(pian)且操作壓(ya)力可達其(qi)最(zui)小(xiao)爆(bao)(bao)(bao)(bao)破(po)壓(ya)力90％以(yi)上的(de)(de)(de)(de)優點(dian)。細分(fen)之下，反(fan)(fan)拱(gong)(gong)(gong)型(xing)(xing)(xing)爆(bao)(bao)(bao)(bao)破(po)片(pian)(pian)(pian)(pian)(pian)(pian)包括反(fan)(fan)拱(gong)(gong)(gong)刻(ke)槽型(xing)(xing)(xing)、反(fan)(fan)拱(gong)(gong)(gong)腭(e)齒型(xing)(xing)(xing)以(yi)及反(fan)(fan)拱(gong)(gong)(gong)刀架型(xing)(xing)(xing)等。
三、爆破片的特點
爆破(po)片與(yu)安全閥比(bi)較，具有結構(gou)簡單、靈(ling)敏、可靠(kao)、經濟、無泄漏、適(shi)用性強等(deng)優(you)越性，但也有其(qi)局限(xian)性，其(qi)特點如下(xia)：
（1）密封性能好，在設(she)備正常工作壓力下(xia)能保持嚴(yan)密不漏。
（2）泄壓反應迅速，爆破(po)片(pian)的動(dong)作一般在2～10ms內(nei)完成(cheng)，而安(an)全(quan)閥則因為機(ji)械滯后(hou)作用，全(quan)部動(dong)作時間要高1～2個數(shu)量級。
（3）對黏稠性或(huo)粉末狀污物不敏感。即使氣(qi)體中含(han)有(you)一定量的污物也(ye)不致影響它(ta)的正常動(dong)作，不像安全閥那樣，容易黏結或(huo)堵塞。
（4）爆破(po)元件（膜片）動作后不能復位(wei)，不但設備內介(jie)質全部流(liu)失，設備也(ye)得中止運行。
（5）動作壓力(li)不(bu)太(tai)穩定，爆破片的爆破壓力(li)允許偏差一(yi)般都比安全閥(fa)的穩定壓力(li)允許偏差大(da)一(yi)些。
（6）爆破片的(de)使(shi)用壽命較(jiao)短，常因疲勞而早期失效。
四(si)、爆破(po)片的適用場(chang)所(suo)
（1）獨立的壓力容器和(he)／或(huo)(huo)壓力管(guan)道(dao)系統(tong)設有安(an)全閥(fa)、爆破片裝置或(huo)(huo)這二者的組合裝置。
（2）滿足(zu)下列情(qing)況之一應優(you)先選用爆破(po)片：
①. 壓力有可(ke)能迅速上升(sheng)的(de)；
②. 泄(xie)放介(jie)質含有顆(ke)粒、易沉淀、易結(jie)晶、易聚合和(he)介(jie)質黏度較大；
③. 泄放介質有(you)強腐蝕性，使(shi)用安全閥時其價值很(hen)高(gao)；
④. 工藝介質十分昂(ang)貴或有劇毒，在(zai)工作過程中不允(yun)許有任何(he)泄(xie)漏，應與安全閥(fa)串聯使用；
⑤. 工作(zuo)壓力(li)很低(di)或很高(gao)時，選用安全閥(fa)則其制造(zao)比較困難；
⑥. 當使用(yong)溫度較低而影響安全閥(fa)工作特性時；
⑦. 需要(yao)較大泄放面(mian)積。
（3）對(dui)于一次性使用(yong)的(de)管(guan)路系(xi)統（如開車吹掃的(de)管(guan)路放空系(xi)統），爆破(po)片的(de)破(po)裂(lie)不影響(xiang)操作和生(sheng)產的(de)場合，設置爆破(po)片。
（4）為減少爆破片破裂后的工藝介(jie)質的損失，可(ke)與安全閥串聯使用。
（5）作為壓(ya)力容器的(de)附加安全(quan)(quan)設施，可與安全(quan)(quan)閥并(bing)聯使(shi)用(yong)，例(li)如爆破片僅用(yong)于(yu)火災情況下的(de)超壓(ya)泄(xie)放。
（6）為增加異常工況（如火災等）下的泄放(fang)面積，爆破片可(ke)并(bing)聯使用(yong)。
（7）爆破片不適用于經(jing)常(chang)超壓和溫度波(bo)動很大的場合(he)。
五、爆破片選用程序(xu)
（1）確定被保(bao)護設備或壓力管道系統是(shi)否需(xu)要設置爆破片。
（2）根據工藝(yi)介質和操作條件確(que)定爆破片的(de)形式及材料。
（3）根據被保護管道系統的最(zui)(zui)高壓力及選用的爆(bao)破(po)(po)(po)片(pian)形(xing)式，按標準規范確定(ding)爆(bao)破(po)(po)(po)片(pian)的最(zui)(zui)小標定(ding)爆(bao)破(po)(po)(po)壓力，設計(ji)爆(bao)破(po)(po)(po)壓力。
（4）根據工藝(yi)條件、物(wu)理參(can)數(shu)計算爆破片(pian)的(de)安全泄放量，選定(ding)爆破片(pian)的(de)泄放面積和(he)泄放口徑(jing)。
（5）填寫爆破片(pian)裝置(zhi)規格書，提供給材料采購(gou)專業，作為訂(ding)貨的技(ji)術(shu)條件。
六、爆破片有關標準(zhun)規(gui)范(fan)
HG/T 20570.3《工藝系(xi)統工程設計技(ji)術規(gui)定--爆破片的設置和選用》
GB 567《爆(bao)破(po)片與爆(bao)破(po)片裝置(zhi)》
GB 12353《拱(gong)型(xing)金(jin)屬爆破(po)片裝(zhuang)置(zhi)分類與安(an)裝(zhuang)尺寸(cun)》
GB/T 14566《正拱形金(jin)屬(shu)爆破片型式與參數》
GB/T 14567《反拱形金屬爆破片(pian)型式與參數》
GB/T 14568《開縫形金屬爆破片型式與參數》
GB/T 16181《爆破片裝置夾持器型式和(he)外(wai)形尺寸》
七(qi)、安全閥(fa)與爆破(po)片性能比較
安全閥與爆破片性(xing)能比較見表6.3.13。
