一、校驗準備及外觀檢查
1、所有(you)測(ce)試(shi)用(yong)儀器均須提(ti)前30分鐘(zhong)通電預熱;
2、試驗氣源壓力要滿(man)足、0.6±0.1Mpa、;
3、執行機(ji)構外觀(guan)無明顯(xian)(xian)損(sun)傷,導氣銅管無明顯(xian)(xian)癟痕且(qie)裝配牢固(gu);
4、位置變送器(qi)連(lian)接螺(luo)桿(gan)長(chang)度(du)必須(xu)符合被檢執行機構(gou)型號(hao)的(de)(de)技術要求(qiu);緊固在變送器(qi)軸上(shang)的(de)(de)連(lian)桿(gan)與連(lian)接螺(luo)桿(gan)所構(gou)成的(de)(de)平(ping)面(mian)應(ying)垂直于水(shui)平(ping)面(mian);
二、檢驗標準和方法
1、將(jiang)氣動執行器固定于(yu)校驗臺上,分別接好氣源、控制氣源和位(wei)移檢(jian)測連桿;將(jiang)校驗臺上儀表(biao)調(diao)校準確;
2機械零(ling)(ling)點(dian)校(xiao)準:輸入4mA電流信號(hao)(0%),控制氣(qi)信號(hao)應(ying)為(wei)0.02Mpa,此時氣(qi)缸活塞(sai)行程(cheng)(cheng)應(ying)為(wei)零(ling)(ling);如果(guo)不為(wei)零(ling)(ling),可通過調(diao)整(zheng)(zheng)調(diao)零(ling)(ling)螺(luo)(luo)桿上的螺(luo)(luo)帽(mao)調(diao)整(zheng)(zheng)零(ling)(ling)點(dian)(零(ling)(ling)點(dian)高了緊螺(luo)(luo)帽(mao));零(ling)(ling)點(dian)和量程(cheng)(cheng)需要反復調(diao)整(zheng)(zheng);零(ling)(ling)點(dian)誤差要≤1%;
3、機(ji)械滿量(liang)(liang)程(cheng)(cheng)(cheng)校準:輸入(ru)20mA電流(liu)信號(100%),控制氣信號應為(wei)0.10Mpa,此時氣缸活塞(sai)行程(cheng)(cheng)(cheng)應為(wei)上限(xian)值;如果不為(wei)上限(xian)值,可通過(guo)調(diao)整(zheng)量(liang)(liang)程(cheng)(cheng)(cheng)拉簧(huang)的松緊來(lai)調(diao)整(zheng)量(liang)(liang)程(cheng)(cheng)(cheng)(量(liang)(liang)程(cheng)(cheng)(cheng)小了松拉簧(huang),量(liang)(liang)程(cheng)(cheng)(cheng)大(da)了緊拉簧(huang));零(ling)點和量(liang)(liang)程(cheng)(cheng)(cheng)需要反復調(diao)整(zheng);滿量(liang)(liang)程(cheng)(cheng)(cheng)誤差(cha)要≤1%;
4、機械量(liang)(liang)程中點(dian)定位(wei):零點(dian)和量(liang)(liang)程調準后,輸入12mA電流信號(50%,、0.06Mpa),調整位(wei)置變送器(qi)連接桿的位(wei)置,使其(qi)在該點(dian)要保持與水平(ping)面垂(chui)直;
5、全行(xing)程偏差(cha)校準:輸入(ru)控制(zhi)氣信號0.02Mpa(0%),然(ran)后逐漸增(zeng)加(jia)輸入(ru)信號0.036、Mpa(20%)、0.052、Mpa(20%)、0.068、Mpa(60%)、0.084、Mpa(80%)、0.1、Mpa(100%),使氣缸活(huo)塞(sai)走完全行(xing)程,各點偏差(cha)均要≤1.5%;
6,非線(xian)(xian)性偏(pian)差(cha)測試:輸入(ru)控制氣信(xin)(xin)號(hao)(hao)0.02Mpa(0%),然后逐漸增加輸入(ru)信(xin)(xin)號(hao)(hao)直至0.10Mpa(100%),再(zai)將(jiang)信(xin)(xin)號(hao)(hao)降至為0.02Mpa(0%),使執行(xing)(xing)機構走完全行(xing)(xing)程(cheng)(cheng),并記錄下每增減0.008Mpa信(xin)(xin)號(hao)(hao)壓力對應的行(xing)(xing)程(cheng)(cheng)值,其實(shi)際壓力━行(xing)(xing)程(cheng)(cheng)關系與理(li)論值之間(jian)的非線(xian)(xian)性偏(pian)差(cha)要≤1%;※
7、正(zheng)反行(xing)程(cheng)變差(cha)測(ce)試:與(yu)非(fei)線性偏差(cha)測(ce)試方法相同(tong),實際正(zheng)反壓力━行(xing)程(cheng)關系(xi)中(zhong),同(tong)一氣壓值(zhi)下(xia)的(de)氣缸活(huo)塞正(zheng)反行(xing)程(cheng)值(zhi)的(de)最(zui)大差(cha)值(zhi)要≤1%;
8、靈敏度測試(shi):分別在(zai)信號(hao)壓(ya)(ya)(ya)力(li)0.03、0.06、0.09Mpa的(de)行程處,增加和降(jiang)低氣(qi)壓(ya)(ya)(ya),測試(shi)在(zai)氣(qi)缸活塞桿開始(shi)移動(dong)0.1mm時所需要(yao)的(de)信號(hao)壓(ya)(ya)(ya)力(li)變(bian)(bian)化(hua)值,其(qi)最大變(bian)(bian)化(hua)要(yao)≤0.2%;
9,活塞氣缸的(de)(de)(de)密封性測試:將0.5、Mpa的(de)(de)(de)壓(ya)力接入氣缸的(de)(de)(de)任一(yi)氣室中,然后切(qie)斷氣源,在(zai)分10鐘內(nei),氣缸內(nei)壓(ya)力的(de)(de)(de)下(xia)降(jiang)值不應超(chao)過0.01、Mpa;
10、位(wei)置變(bian)送(song)器電氣(qi)零點檢測:打(da)開位(wei)置變(bian)送(song)器上蓋(gai),接好電線;輸入12mA電流(liu)信號(0.06、Mpa),此(ci)時調整變(bian)送(song)器內圓形偏心輪(lun),使(shi)其上面的黑線與線路(lu)板上面的白線對齊;然后(hou)再輸入4mA電流(liu)(0.02、Mpa),此(ci)時可調整變(bian)送(song)器內調零電位(wei)器使(shi)輸出電流(liu)為4mA;電氣(qi)零點誤差應≤1%;
11、位(wei)置變(bian)送(song)器(qi)電(dian)(dian)(dian)氣滿量(liang)程(cheng)(cheng)檢測(ce):輸入20mA電(dian)(dian)(dian)流信號(0.1、Mpa),此(ci)時可(ke)調(diao)整(zheng)變(bian)送(song)器(qi)內調(diao)量(liang)程(cheng)(cheng)電(dian)(dian)(dian)位(wei)器(qi)使輸出電(dian)(dian)(dian)流為20mA;電(dian)(dian)(dian)氣滿量(liang)程(cheng)(cheng)誤差應≤1%;
12、位置反饋(kui)電流(liu)(liu)全行(xing)程偏差(cha)校準(zhun):輸入4mA電流(liu)(liu)(0%),然后逐漸(jian)增(zeng)加輸入信號8mA電流(liu)(liu)(25%)、12mA電流(liu)(liu)(50%)、16mA電流(liu)(liu)(75%)、20mA電流(liu)(liu)(100%),考(kao)慮到(dao)直線位移轉換成角度變化的非(fei)線性誤差(cha),0%、50%、100%點(dian)反饋(kui)電流(liu)(liu)誤差(cha)應(ying)≤1%,25%、75%點(dian)反饋(kui)電流(liu)(liu)誤差(cha)應(ying)≤2%;
13、位(wei)置反(fan)饋(kui)(kui)電流(liu)正(zheng)反(fan)行程(cheng)變(bian)差測試(shi):同氣缸正(zheng)活塞(sai)反(fan)行程(cheng)變(bian)差測試(shi)方法相(xiang)同,實(shi)際正(zheng)反(fan)位(wei)置反(fan)饋(kui)(kui)電流(liu)━行程(cheng)關系中,同一反(fan)饋(kui)(kui)電流(liu)值(zhi)下的氣缸活塞(sai)正(zheng)反(fan)行程(cheng)值(zhi)的最大差值(zhi)要(yao)≤1%;
14、作好(hao)校驗(yan)記錄,按校驗(yan)記錄表上的(de)內容逐項認真填寫,檢(jian)驗(yan)人(ren)員(yuan)必須簽字;
15、上述各項測(ce)試(shi)做完合(he)格后(hou)(hou),應將(jiang)位置變(bian)送器內接線端(duan)子插好(hao),擰緊后(hou)(hou)蓋,然后(hou)(hou)將(jiang)閥(fa)門定位器氣源(yuan)入口用塑(su)料堵頭堵好(hao);