为焊接式管接头：特点是连接牢固，利用球面进行密封，简单可靠。但厚壁钢管，装拆不便且必须保证焊接质量。

For welded pipe joint: it is characterized by strong connection and sealing with spherical surface, simple and reliable. But thick wall steel pipe, it is inconvenient to install and dismantle and the quality of welding must be guaranteed.

为卡套式管接头：特点是利用卡套卡住油管进行密封，轴向尺寸要求不严，装拆方便。.对油管的径向尺寸精度要求较高，为此要选用冷拔无缝钢管。

For the jacket type pipe joint: the feature is to use the jacket to hold the oil pipe for sealing, the axial size is not strict, and the installation is convenient. The precision of the radial dimension of the tubing is higher, so the cold drawn seamless steel pipe should be selected.

为扩口式管接头：利用油管管端的扩口在管套压紧下进行密封，结构简单。.适用于铜管、薄壁钢管、尼龙管和塑料管等低压管道的连接。

It is an expanding type pipe joint: the expansion of the pipe end of the tubing is sealed under the pressure of the pipe sleeve, and the structure is simple. It is suitable for the connection of copper pipe, thin-walled steel tube, nylon tube and plastic pipe.

为扣压式管接头：用于连接高压软管。适用于中、低压系统。

For pressing type pipe joint for connecting high pressure hose. It is suitable for medium and low pressure systems.