Axial expansion joints are designed for axial movement only, though in certain circumstances will accommodate a small lateral offset. These expansion joints do not restrain the internal pressure thrust. The piping designer must provide the system with separate anchoring and guiding to resist the pressure thrust. Where small thermal movements are involved and proper anchoring and guiding is feasible, a single expansion joint is the most economical installation.

Axial flow compressor is an improvement on the centrifugal compressor. The key improvement is that axial flow compressors work without radically changing the direction of gas flow. An axial flow compressor typically has a set of fixed inlet guide vanes to condition the incoming gas. There are then multiple compressor stages, each consisting of a set of rotating blades much like a propeller that force the gas to the rear and then a set of fixed stator blades that condition the air ready for the next compressor stage. The gas conditioning done by the stator blades is needed to ensure reasonable efficiency. Without the stator blades the gas would rotate with the rotor blades giving a bit drop in efficiency. Axial flow compressors are typically used in the compression stage of turbine engines.

Axial flow control valves or grid valves are appropriate for low-pressure applications and high volume flows and is available with a relatively short span. The low-pressure end, which is the drive end is a turning (barring) gear used to rotate the shaft when the turbine is cooling down. These turning devices are often utilized on high inlet temperature turbines over 850 degF (455 deg C) and when the bearing span is over 150 inches (3810 mm).

Axial flow control valve consists of a valve body. It has a flow passage containing there in a cylinder and an annular sleeve both are held in position by a positioning sleeve. The annular sleeve has a wall member formed with a multi-pores means for providing a number of V-shaped or elongate ports for reducing noise and vibration of fluid flow. A push rod is axially movably disposed within the cylinder, having one end attached with a resiliently biasing means for resiliently engaging a valve piston axially displaceable within the cylinder and the annular sleeve for controlling fluid flow. The positioning sleeve is formed with a truncated conical valve seat to associate with the valve piston for sealingly occluding fluid flow. O-rings made of resiliently metallic or ceramic material are disposed on the valve piston and/or the push rod for sealing the axially movable elements, so that the valve can be used in a high-temperature environment.

Axial flow pump is a common type of water pump that essentially consists of a propeller in a tube. The propeller can be driven directly by a sealed motor in the tube or by a right-angle drive shaft that pierces the tube. The main advantage of AFP is that it can easily be adjusted to run at peak efficiency at low-flow/high-pressure and high-flow/low-pressure by changing the pitch on the propeller. These pumps have the smallest of the dimensions among any of the conventional pumps and are more suited for low heads and higher discharges.

Axial flow turbine consists of one or more stages located immediately to the rear of the engine combustion chamber. The turbine extracts kinetic energy from the expanding gases as the gases come from the burner, converting this kinetic energy into shaft power to drive the compressor and the engine accessories. The turbine can be classified as impulse and reaction turbine. In the impulse turbine, the gases will be expanded in the nozzle and passed over to the moving blades. The moving blades convert this kinetic energy into mechanical energy and also direct the gas flow to the next stage or to exit.