管(guan)線(xian)清(qing)管(guan)的(de)(de)(de)目(mu)的(de)(de)(de)是清(qing)除焊接時留(liu)在(zai)(zai)管(guan)道內的(de)(de)(de)泥沙、焊渣等雜(za)物，為(wei)管(guan)線(xian)測(ce)徑(jing)和管(guan)線(xian)正(zheng)常運(yun)行提供保障。管(guan)線(xian)測(ce)徑(jing)的(de)(de)(de)目(mu)的(de)(de)(de)是在(zai)(zai)試壓之前(qian)確定管(guan)道存在(zai)(zai)的(de)(de)(de)失(shi)圓、皺痕、凹坑(keng)或(huo)其它變形的(de)(de)(de)程度(du)和管(guan)線(xian)的(de)(de)(de)通過能力。

　　管(guan)(guan)道清(qing)管(guan)(guan)和測徑(jing)是在線(xian)路焊接(jie)和回填(tian)之后、水壓試驗之前，利用空(kong)壓機向(xiang)管(guan)(guan)段內(nei)(nei)注入壓縮空(kong)氣(qi)，推動機械清(qing)管(guan)(guan)器進行管(guan)(guan)段內(nei)(nei)雜物(wu)清(qing)掃和內(nei)(nei)徑(jing)測量(liang)的(de)一道重要工序。

　　為(wei)(wei)了達到較佳清(qing)管(guan)(guan)、測徑效果和準確地判斷缺陷(xian)位置(zhi)，管(guan)(guan)線通常采取分段(duan)清(qing)管(guan)(guan)、測徑方(fang)法，其段(duan)落(luo)劃分通常為(wei)(wei)相鄰閥室間管(guan)(guan)段(duan)或閥室與相鄰清(qing)管(guan)(guan)站間的管(guan)(guan)段(duan)，長度(du)一般為(wei)(wei)30公里左右(you)，小于試(shi)壓段(duan)長度(du)。

　　清管(guan)和(he)測(ce)(ce)徑(jing)(jing)用(yong)的(de)清管(guan)器直徑(jing)(jing)通(tong)常比(bi)管(guan)道內徑(jing)(jing)要過盈5%至8%。測(ce)(ce)徑(jing)(jing)用(yong)的(de)清管(guan)器和(he)清管(guan)用(yong)的(de)清管(guan)器大致相同(tong)，只是前者(zhe)多裝有一(yi)塊測(ce)(ce)徑(jing)(jing)板(ban)。測(ce)(ce)徑(jing)(jing)板(ban)一(yi)般為(wei)(wei)鋁制，厚度通(tong)常為(wei)(wei)12毫米至15毫米。測(ce)(ce)徑(jing)(jing)板(ban)的(de)直徑(jing)(jing)取決于所測(ce)(ce)管(guan)段的(de)內徑(jing)(jing)，并需考(kao)慮到該管(guan)段的(de)變徑(jing)(jing)設計，一(yi)般為(wei)(wei)所測(ce)(ce)管(guan)段最小理論(lun)內徑(jing)(jing)的(de)95%。

　　清(qing)(qing)管(guan)(guan)(guan)(guan)和測(ce)(ce)徑(jing)(jing)(jing)(jing)的(de)施工過程(cheng)完全相同。在清(qing)(qing)管(guan)(guan)(guan)(guan)、測(ce)(ce)徑(jing)(jing)(jing)(jing)之前，先在管(guan)(guan)(guan)(guan)線(xian)兩端安裝(zhuang)臨時收(shou)發球(qiu)筒(tong)，收(shou)發球(qiu)筒(tong)安裝(zhuang)完成后(hou)將(jiang)清(qing)(qing)管(guan)(guan)(guan)(guan)或測(ce)(ce)徑(jing)(jing)(jing)(jing)用的(de)清(qing)(qing)管(guan)(guan)(guan)(guan)器(qi)(qi)裝(zhuang)入(ru)發球(qiu)筒(tong)，然后(hou)啟動空氣(qi)壓(ya)(ya)縮(suo)(suo)機向發球(qiu)筒(tong)內注入(ru)壓(ya)(ya)縮(suo)(suo)空氣(qi)，壓(ya)(ya)縮(suo)(suo)空氣(qi)推(tui)動清(qing)(qing)管(guan)(guan)(guan)(guan)器(qi)(qi)向前移動，直到清(qing)(qing)管(guan)(guan)(guan)(guan)器(qi)(qi)將(jiang)管(guan)(guan)(guan)(guan)線(xian)內泥沙、焊渣等雜物推(tui)到收(shou)球(qiu)筒(tong)內，停止向管(guan)(guan)(guan)(guan)線(xian)內注入(ru)壓(ya)(ya)縮(suo)(suo)空氣(qi)，并(bing)打(da)開收(shou)發球(qiu)筒(tong)上的(de)排氣(qi)閥(fa)門進行排氣(qi)。當管(guan)(guan)(guan)(guan)線(xian)內壓(ya)(ya)力降到大(da)氣(qi)壓(ya)(ya)力時，打(da)開收(shou)球(qiu)筒(tong)，檢查清(qing)(qing)管(guan)(guan)(guan)(guan)或測(ce)(ce)徑(jing)(jing)(jing)(jing)效果。若(ruo)收(shou)球(qiu)筒(tong)內泥沙、焊渣等雜物總體(ti)積(ji)不超過5升，清(qing)(qing)管(guan)(guan)(guan)(guan)合(he)格。測(ce)(ce)徑(jing)(jing)(jing)(jing)清(qing)(qing)管(guan)(guan)(guan)(guan)器(qi)(qi)到達(da)收(shou)球(qiu)筒(tong)后(hou)，拆下清(qing)(qing)管(guan)(guan)(guan)(guan)器(qi)(qi)上的(de)測(ce)(ce)徑(jing)(jing)(jing)(jing)板，若(ruo)測(ce)(ce)徑(jing)(jing)(jing)(jing)板沒有明顯變形，測(ce)(ce)徑(jing)(jing)(jing)(jing)合(he)格。復雜的(de)管(guan)(guan)(guan)(guan)道可采用建立(li)背壓(ya)(ya)的(de)方法(fa)進行清(qing)(qing)管(guan)(guan)(guan)(guan)、測(ce)(ce)徑(jing)(jing)(jing)(jing)。