天天综合天天添夜夜添狠狠添 I 国产午夜小视频 I 91久久综合亚洲鲁鲁五月天 I 无码人妻aⅴ一区二区三区69岛 I 亚洲kkkk4444在线播放 I 性色生活片 I 亚洲人成网站在线播放大全 I 国产妇女精品 I 午夜在线视频一区二区 I 无码国产片观看 I 久久婷婷综合缴情亚洲狠狠 I 欧美熟妇乱子伦xx视频 I 日本高清网 I 二区三区av I 超碰免费福利 I 黄色片高清 I 久久精品成人热国产成 I 国产成人亚洲欧洲在线 I 国产玖玖视频 I 成人综合区另类小说色区 I 国产免费看又黄又大又污的胸 I 国产中文字幕第一页 I 一区二区激情日韩五月天 I 日本天堂免费 I 亚洲视频999 I 欧美韩日 I 中文字幕av有码 I 尤物视频一区 I 琪琪亚洲精品午夜在线 I 日韩黄色三级

Since the 1990s, there has been increasingly higher demand placed on lubricants. These demands were driven by heightened environmental awareness as well as manufacturers’ requirements. Following the International Lubricants Standardization and Approval Committee (ILSAC) recommendation for the use of SAE 10W/30 viscosity grade engine oil, there was a trend towards the use of low-viscosity and low-emission lubricants. As the key raw material used in lubricants, lube base stocks should possess the following characteristics: low viscosity, low volatility, high viscosity index, and good oxidation stability to name a few. Broadly speaking, American Petroleum Institute’s (API) Group Ⅱ, Group Ⅲ and poly-alpha-olefin (PAO) synthetic oils possess these characteristics (unlike conventional solvent refined base oils). Group II and Group III lube base stocks are often suitable and highly economical substitutes for expensive synthetic base oils to produce premium multi-grade lubricants such as GF-1, GF-2, GF-3 and GF-4.

■ Typically, solvent extracted base stocks fall into Group I.
■ Hydrotreated base stocks and some lower quality hydrocracked base oils into Group II.
■ Hydrocracked base stocks are often categorized in Group III.
■ The Group IV base stock is poly-alpha-olefins (PAOs).
■ The Group V category contains synthetics other than PAOs, esters and naphthenics (with typical VIs lower than 80).

S-OIL’s aramcoULTRA series products (aramcoULTRA4/S6/S8) fall into the Group III category and exhibit superior physical properties and performance over Group I and Group II products.