你知道(dao)開口閃點試驗(yan)儀的實驗(yan)原理嗎

實驗原理︰

按(an)(an)照所用(yong)閃(shan)(shan)點(dian)測(ce)定器的型式(shi),閃(shan)(shan)點(dian)可(ke)分為(wei)閉口(kou)閃(shan)(shan)點(dian)和開(kai)口(kou)閃(shan)(shan)點(dian)兩(liang)種(zhong)。每種(zhong)油(you)品(pin)是測(ce)閉口(kou)閃(shan)(shan)點(dian)還(huan)是測(ce)開(kai)口(kou)閃(shan)(shan)點(dian)要按(an)(an)產(chan)品(pin)質量指(zhi)標規定進行(xing)。一般(ban)地,蒸(zheng)發(fa)性(xing)較大的石油(you)產(chan)品(pin)多(duo)測(ce)閉口(kou)閃(shan)(shan)點(dian),因(yin)為(wei)測(ce)定開(kai)口(kou)閃(shan)(shan)點(dian)時,油(you)品(pin)受熱(re)后所形(xing)成的蒸(zheng)氣不斷向(xiang)周圍空(kong)氣擴散,使測(ce)得的閃(shan)(shan)點(dian)偏高。對(dui)多(duo)數潤(run)滑油(you)及重質油(you),由(you)于蒸(zheng)發(fa)性(xing)小,則多(duo)測(ce)開(kai)口(kou)閃(shan)(shan)點(dian)。

閉口閃(shan)點的(de)測定原理是把試(shi)樣(yang)(yang)裝入(ru)油杯中(zhong)到環狀標記處(chu),把試(shi)樣(yang)(yang)在連(lian)續攪拌下用(yong)很慢的(de)、恒(heng)定的(de)速度加熱,在規定的(de)溫度間隔,同時(shi)中(zhong)斷攪拌的(de)情況下,將(jiang)一小火(huo)焰(yan)引入(ru)杯中(zhong),試(shi)驗(yan)火(huo)焰(yan)引起試(shi)樣(yang)(yang)上的(de)蒸(zheng)氣閃(shan)火(huo)時(shi)的(de)zui低(di)溫度作為閉口閃(shan)點。

開(kai)口閃點(dian)測定(ding)(ding)原理是把試(shi)(shi)(shi)樣裝入(ru)試(shi)(shi)(shi)驗杯中到規定(ding)(ding)的(de)(de)(de)刻線。首先升高試(shi)(shi)(shi)樣的(de)(de)(de)溫(wen)(wen)度,然后緩慢升溫(wen)(wen),當接近閃點(dian)時(shi),恒速升溫(wen)(wen)。在規定(ding)(ding)的(de)(de)(de)溫(wen)(wen)度間隔,以一個小(xiao)的(de)(de)(de)試(shi)(shi)(shi)驗火(huo)焰橫(heng)著通(tong)過試(shi)(shi)(shi)杯,用試(shi)(shi)(shi)驗火(huo)焰使液體表面上(shang)的(de)(de)(de)蒸氣發(fa)生點(dian)火(huo)的(de)(de)(de)zui低溫(wen)(wen)度作為(wei)開(kai)口閃點(dian)的(de)(de)(de)測定(ding)(ding)結(jie)果。