（1）工程機(ji)(ji)(ji)械(xie)使(shi)用(yong)(yong)(yong)初(chu)期(qi)(qi)(qi)階(jie)段的故(gu)(gu)(gu)障(zhang)特點。工程機(ji)(ji)(ji)械(xie)在使(shi)用(yong)(yong)(yong)初(chu)期(qi)(qi)(qi)(相當于走合期(qi)(qi)(qi))其故(gu)(gu)(gu)障(zhang)是由高(gao)(gao)(gao)到(dao)低(di)(降曲(qu)線)，使(shi)用(yong)(yong)(yong)初(chu)期(qi)(qi)(qi)故(gu)(gu)(gu)障(zhang)率高(gao)(gao)(gao)低(di)是隨(sui)制造(zao)或維修質(zhi)量和(he)走合時期(qi)(qi)(qi)的使(shi)用(yong)(yong)(yong)有關(guan)．如果工程機(ji)(ji)(ji)械(xie)制造(zao)或修理質(zhi)量高(gao)(gao)(gao)，并能正確(que)地使(shi)用(yong)(yong)(yong)與維護(hu)。那么，初(chu)期(qi)(qi)(qi)故(gu)(gu)(gu)障(zhang)率就(jiu)低(di)。否則早(zao)期(qi)(qi)(qi)故(gu)(gu)(gu)障(zhang)率會(hui)高(gao)(gao)(gao)。早(zao)期(qi)(qi)(qi)故(gu)(gu)(gu)障(zhang)多(duo)地是聯接(jie)螺(luo)栓松(song)動或松(song)脫；管道(dao)接(jie)頭松(song)動或松(song)脫：殘(can)留金屬屑或鑄造(zao)砂易堵塞油(you)道(dao)或夾在相對運動摩(mo)擦中拉傷機(ji)(ji)(ji)件(jian)(如液壓系統中的執(zhi)行(xing)機(ji)(ji)(ji)構(gou)油(you)缸)造(zao)成(cheng)漏(lou)油(you)，調(diao)整(zheng)后的間(jian)隙(xi)或壓力發生(sheng)變化，使(shi)機(ji)(ji)(ji)件(jian)不(bu)(bu)能執(zhi)行(xing)規(gui)定能力，有些接(jie)合因(yin)螺(luo)栓不(bu)(bu)緊而漏(lou)水、漏(lou)油(you)、漏(lou)氣(qi)等。

（2）工程機(ji)械(xie)正(zheng)常(chang)使用(yong)階段(duan)的故(gu)(gu)障特點。工程機(ji)械(xie)走(zou)合期結束(shu)后(hou)，進人正(zheng)常(chang)使用(yong)階段(duan)。工程機(ji)械(xie)在這個階段(duan)內運行，只要(yao)按規定維護和正(zheng)確使用(yong)，一般不會(hui)發生(sheng)故(gu)(gu)障，即便發生(sheng)故(gu)(gu)障，也是隨機(ji)性(xing)的故(gu)(gu)障。