CF,KF,NW,ISO 区别
1.CF 系列:CF 法兰比较容易区分，主要是用在超 高真空系统上的密封连接，其主要密封方式是金属密封即铜垫片密封。需要注意的是铜垫片在使用一次后密封效果会很差，如果对真空度要求较高的系统，法兰每拆卸一次，就需要更换垫片。这类法兰有标准规格，如 CF35， 其中铜垫片也有标准件买。
2.KF 系列:KF 是日常真空系统中比较常见的密封连接方式，主要应用在高真空系统中。其主要密封方式是橡胶圈密封。
3.规格从 KF10-KF50,通常情况下 KF 连接的管道尺寸是相对于英寸规格来说的。即 KF25 对应的管道是 25.4*1.65mm，依此类推(有的要求特殊管道，法兰的焊 接尺寸可以定制)。
4.KF 大的到 KF50（配管是 50.8*1.65mm)之后的真空连接就是 ISO系列。KF 系列常见，一般的真空配件公司都有。
5.ISO 系列:ISO 也是用于高真空系统中的配件，小规格是 ISO63（配管是 63.5*1.65mm）
再往后面是 ISO80、ISO100、ISO160 直至 ISO320 甚至更大规格，链接方式是双卡头链接, 主要是两个 ISO 的法兰片，中间加密封圈，然后用四个双卡头卡住法兰片进行连接。
6.要注意的是通常情况下 ISO 系列的密封圈相对于 KF 系列的真空密封圈除了有中 心支架和氟橡胶材质的密封圈外，还多了一个铝制的弹簧外圈，其主要作用是防止密封圈滑脱。
7.因为 ISO 系列的管路尺寸相对较大，密封圈套在中 心支架上面受到机台的震动或者温度的影响，如果没有固定的话会滑脱，影响密封。
8.NW 系列:NW 同样是用在高真空系统中的真空配件，是日本的规范，所以 NW 的真空配件在日企或者日本设备里面用到的相对来说多一些。
9.前面我们说过，ISO 系列的是两片ISO的法兰片和四个双卡钩进行连接，而 NW 的链接方式是两片 NW 的法兰在一起，用链式卡箍进行连接（N63 的法兰外观上就是大一号的 NW50 的法兰）。
基本上 NW50 以下尺寸是可以与 KF 通用的。
CF, KF, NW, ISO difference 1. CF series: CF flanges are easier to distinguish. They are mainly used for sealing connections in ultra-high vacuum systems. The main sealing method is metal sealing, that is, copper gasket sealing. It should be noted that the sealing effect of the copper gasket will be very poor after using it once. If the system requires a high degree of vacuum, the gasket needs to be replaced every time the flange is removed. This type of flange has standard specifications, such as CF35, and copper gaskets are also available as standard parts.
2. KF series: KF is a relatively common sealing connection method in daily vacuum systems, mainly used in high vacuum systems. The main sealing method is rubber ring sealing.
3. The specifications range from KF10-KF50. Normally, the size of the pipe connected by KF is relative to the inch specifications. That is, the pipe corresponding to KF25 is 25.4*1.65mm, and so on (some require special pipes, and the flange welding size can be customized).
4. Vacuum connection after KF is as large as KF50 (piping is 50.8*1.65mm) is ISO series. The KF series are common and common vacuum fitting companies have.
5. ISO series: ISO is also an accessory used in high vacuum systems, the small size is ISO63 (the piping is 63.5*1.65mm)
Further to the back are ISO80, ISO100, ISO160 to ISO320 and even larger specifications. The connection method is double-clamp connection, mainly two ISO flanges, with a sealing ring in the middle, and then four double-clamps to clamp the flange The pieces are connected.
6. It should be noted that in general, ISO series sealing ring has a center bracket and fluorine rubber sealing ring compared to KF series vacuum sealing ring, but also an aluminum spring outer ring. Its main function is Prevent the seal ring from slipping off.
7. Because the pipe size of the ISO series is relatively large, the sealing ring sleeved on the center bracket is affected by the vibration or temperature of the machine. If it is not fixed, it will slip off and affect the sealing.
8. NW series: NW is also a vacuum fitting used in high vacuum systems, which is a Japanese standard, so NW vacuum fittings are relatively more used in Japanese companies or Japanese equipment.
9. As we said before, the ISO series are connected by two ISO flanges and four double hooks, while the NW connection method is that the two NW flanges are connected together and connected by a chain clamp ( The flange of N63 is the flange of NW50 which is one size bigger in appearance).
Basically, sizes below NW50 can be used with KF.
