O形圈是保證高壓清洗機柱塞泵密封性的重要部件，O形密封圈是一種截面為圓形的橡膠圈，因其截面為O形，故稱其為O形密封圈，是液壓與氣壓傳動系統(tǒng)中使用最廣泛的一種。由于O形密封圈用的合成橡膠材料是屬于粘彈性材料，所以初期設(shè)定的壓緊量和回彈堵塞能力經(jīng)長時間的使用，會產(chǎn)生永久變形而逐漸喪失，最終發(fā)生泄漏。因此，O形密封圈需定期進行更換，以免損壞高壓清洗機柱塞泵。O形圈是純膠結(jié)構(gòu)，因此要根據(jù)工作條件，特別是工作壓力來選擇O形圈的材料和硬度，對于中低壓場合，當(dāng)膠料硬度為90時，可耐壓力為150kg/cm2，當(dāng)膠料硬度提高到95度時，不加擋圈耐壓可達700kg/cm2，所以O(shè)形圈膠料的硬度對密封件耐壓性能有極重要的影響。(圖/文www.wxcwjx.com)

英文版：

O ring is an important component for ensuring sealing plunger pump of high-pressure cleaner, O sealing ring is a circular section rubber ring, because of its cross section is O, so the O ring, hydraulic and pneumatic transmission system is one of the most widely used. The synthetic rubber O ring is a viscoelastic material, so the initial set of compression and rebound clogging ability after using for a long time, will produce permanent deformation and gradually lost, eventually leak. Therefore, the O shape sealing ring should be changed regularly, so as not to damage the plunger pump of high-pressure cleaner. O ring is gum structure, so according to the working conditions, especially the work pressure to choose the O ring material and hardness, for low voltage, when the rubber hardness is 90, high pressure 150kg/cm 2, when the rubber material hardness of 95 degrees, without pressure up to 700kg /cm. 2, so the O ring rubber hardness has an important influence on the seal resistance.