常规设计的表面型过滤器，采用相对薄的滤材，允许大流量通过滤芯。
The filter element is pleated in order to increase the surface area and reduce the pressure drop.
这种滤芯通常是褶状的，以增加表面积，减少压力损耗。
The filter is capable of removing solid particles only – and as it utilizes only the surface area, it has a restricted dirt holding capacity.
这种过滤器只能去除固体颗粒，而且因为它只能利用表面，所以纳污容量有限。 See illustrations on pages 14 & 15. 请参看14&15页插图。
Modern oil systems often combine the two cleaning systems, where the depth filter removes the contamination and the surface filter serves as security filter.
现代的油质系统通常综合这两种清洁系统，使用深度型过滤器清除污染，而表面型过滤器作为保障过滤器。
Surface Filter 表面型过滤器
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Element housing O-Ring 壳体O型环 End cap seal 端盖密封 Core 核心
Pleat support band 褶状支撑 Medium support 滤芯支撑 End cap 端盖
Filter element 滤芯
Unfiltered oil entry 未过滤的油的入口
Filtered oil returned to oil circuit 已过滤的油进入原回路 Support layer 支撑层
Filter medium layer 过滤媒介层 Outer filter casing 外滤罩 Oil flow 油液流
Trapped particles 集中的颗粒物 Filter medium 过滤媒介 Support layer 支撑层
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Surface filters have a limited contamination holding capacity, usually between 1 and 100 grams, which makes filter, insert replacement at short intervals necessary in order to ensure efficient filtration.
表面型过滤器的纳污能力有限，通常在1～100克，所以需要经常更换滤芯，以保证过滤的效率。
Surface filters removing particles <20 μm ensure effective protection when installed before an important machine part.
安装重要的机械部件前，表面型过滤器可去除<20 μm的颗粒,起到有效的保护作用。Surface filters do not absorb water. 表面型过滤器不能吸收水份。
Surface filters do not remove oxidation residual deposits. 表面型过滤器不能去除氧化物的残余沉淀。
Depth Filter 深度过滤器
Filter element:滤芯：
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Made as a sandwich of corrugated wood cellulose discs rotated at 90° to the next and bonded together.
由多个波纹状木质纤维片组成，纹路方向正交90°相叠加，就如三明治一样。
This gives a series of connected surfaces with corrugations running north-south and east-west.
如此一系列纹路方向正交的表面相连接。
Two-disc filter sandwich 两片滤片 Filtered oil returned to the oil circuit 已过滤的油回到回路
Unfiltered oil enters under pressure 未过滤油在压力下进入
Outer filter housing 过滤器外壳 Function 功能
Particles pass through the filter maze until they are trapped 颗粒物进入过滤器，直到它们被截留在滤片上
The CJCTM depth filter has a contamination holding capacity of approximately 2 L and only needs replacing every 12 months.
CJCTM深度型过滤器拥有大约2L的纳污能力，并且只需要每12个月更换一次。 Depth filters filter effectively down to 3 μm absolute. 深度型过滤器能有效的过滤小到3微米的颗粒。
Depth filters absorb water and resins (oxidation residuals) 深度过滤器还可吸收水份和树脂（氧化残留物）
Basic filtration definitions 基本的过滤定义
Nominal filtration 标准过滤精度
Ratings are estimated values, indicating a particulate size range at which the filter is claimed to remove a given percentage. There is no standard for this, so consequently, different products/makes cannot be compared.
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评定标准是一个估计值，表明过滤器标称能够去除的百分比含量中所涵盖的微粒的尺寸范围。对此没有一个明确标准，因不同的产品而无法比较。
Operating pressure and concentration of contaminants will affect the retention efficiency of nominal rated filters.
操作压力和污染物的浓度会影响标准过滤精度的过滤器的去除效率。
Absolute filtration 绝对过滤精度
Ratings describe the pore size, indicating the largest size of particle which can pass through the filter. The filter need to apply to a standard test method intended for filter usage.
评定标准描述了孔径大小，标明了可以通过过滤器的最大颗粒的大小，过滤器需要经过标准化的测试方式来实现过滤使用。
The rating of depth filters is often 3 micron absolute or less. The rating of surface filters varies according to the requirements of the components to be protected.
深度过滤器的精度通常是3微米或更小。表面型过滤器的过滤精度，根据要保护的元件的要求而有所不同。
Beta values
are describing filter efficiencies at a given particle size. The value is written ?x, where the “x” represents the particle size in question and the ? is the efficiency, e.g. ?3 = 75, which means that one out of 75 particles of 3 micron size will pass through the filter (1.3% passes though and 98.7% are retained in one pass).
Beta 值是以给出的颗粒尺寸来描述过滤器的过滤效率，写作?x，x表示颗粒尺寸，?是效率，
例如：?3 = 75，意思是75分之一的3微米的颗粒会通过过滤器（1.3%通过，98.7%在一次通过中被截留）
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