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Requirements of axial compensators for pipe rack design: Axial compensators are primarily used to compensate for axial displacement; they can also compensate for lateral displacement or a combined axial and lateral displacement. They have the capability to compensate for angular displacement as well, but general-purpose compensators are generally not used for compensating angular displacement. 1. Main fixing pipe racks shall be installed at the pipe sections where axial compensators are installed, at the blind ends of pipes, at elbows and areas with variable cross-sections, at the sections equipped with stop valves or pressure reducing valves, and at the entrances where side pipelines connect to the main pipeline. The main fixed pipe rack must take into account the static pressure thrust of the bellows as well as the elastic force resulting from deformation. The thrust calculation formula is as follows: Fp = 100 * P * A, where Fp represents the axial force exerted by the compensator (in N), A is the effective area corresponding to the average diameter of the corrugations (in cm2), and P is the maximum pressure in that pipe section (in MPa). The formula for calculating the axial elastic force is as follows: Fx = f * Kx * X. Where FX represents the axial elastic force of the compensator (in N), and KX represents the axial stiffness of the compensator (in N/mm) ； The f-factor: when there is \"pre-deformation\" (including the case where the pre-deformation amount △X=0), f=1/2; otherwise, f=1. In addition to the aforementioned areas, intermediate fixed pipe racks can be installed on the pipeline. The intermediate fixed pipe rack does not need to take into account the effect of pressure thrust. 2. Only one axial type compensator can be installed between the two fixed pipe supports of a pipe segment. 3. One end of the compensator should be close to the fixed pipe rack; if it is too long, guide racks must be installed in accordance with the requirements for the first guide rack. The maximum spacing between other guide racks can be calculated as follows: LGmax – maximum guide spacing (m) ； E-pipe material elastic modulus (N/cm2) ； i-tp pipe cross-sectional moment of inertia (cm4) ； KX – Axial stiffness of the compensator (N/mm), X0 – Displacement amount for compensating adjustment (mm). When the compensator is compressed, the symbol is “+”; when it is stretched, the symbol is “-”. When the pipe wall thickness is designed according to the standard thickness, LGmax can be selected in accordance with relevant standards.