Chemical Engineering - Fluid Mechanics - Discussion

Expansion joint should be the correct answer. As it will protect the pipe from sudden increase or decrease in temperature or any kind of vibration motion which can generally be faced in a underground piping system.

Because a sleeve joint is used to connect two similar coaxial cylindrical pipes or rods.

Give more details about other joints.

A coupling is a device used to connect two shafts together at their ends for the purpose of transmitting power. Couplings do not normally allow disconnection of shafts during operation, however there are torque limiting couplings which can slip or disconnect when some torque limit is exceeded.

A flange is an external or internal ridge, or rim (lip) , for strength, as the flange of an iron beam such as an I-beam or a T-beam; or for attachment to another object, as the flange on the end of a pipe, steam cylinder, etc. , or on the lens mount of a camera; or for a flange of a rail car or tram wheel.

An expansion joint or movement joint is an assembly designed to safely absorb the heat-induced expansion and contraction of various construction materials, to absorb vibration, to hold certain parts together, or to allow movement due to ground settlement or earthquakes. They are commonly found between sections of sidewalks, bridges, railway tracks, piping systems, ships, and other structures.

A sleevejoint is device for joining the ends of two wires or cables together, constructed by forcing the ends of the wires or cables into both ends of a hollow sleeve. And hence this joint is suitable for underground pipelines.