Lateral Expansion Joints
20Pages

Your Flexible Solutions Partner

General information - Lateral expansion joints, - Anchors, pipe supports / guides 3 Pipe guides, pipe supports operating pressure, Pre-stressing diagram/ Expansion joint data sheet 16

General information A lateral expansion joint works in the same way a hinged expansion joint does. It utilizes the ability of a bellows to rotate in angular direction. The lateral movement capability is the result of the angular rotation of the bellows and their center to center distance. The longer the distance between the bellows, the larger is the movement capacity (Fig. 1). A longer center to center distance also results in lower displacement forces of the expansion joint. Lateral expansion joints are independent expansion systems in contrast to single hinged expansion joints. They are...

General information Types Tied universal expansion joints that use tie rods and washer nuts to restrain the pressure thrust forces represent the simplest design of lateral expansion joints. They are suited to compensate for movements in any direction perpendicular to their axis. For higher pressure conditions, the use of a cardanic universal expansion joint is recommended. This type of expansion joint uses tie bars with cardanic hinges to restrain the pressure thrust. They too are suited to compensate for movements in any direction perpendicular to the expansion joint axis. Another...

General information To ensure that the lateral expansion joint compensates for the thermal expansion correctly, pipe anchors and pipe supports / guides must be installed to define the amount and direction of the thermal expansion. According to the peripheral conditions of the installation, this can be achieved by placing two pipe guides adjacent to the elbows on each side of the expansion joint with anchors further away from the location of the expansion joint or by the installation of one anchor and one pipe guide in the afore mentioned positions (Fig. 8). The pipe supprts / guides must...

Calculations Sleeves We recommend the installation of expansion joints with sleeves if high-frequency oscillations or turbulences are to be expected in the medium, or if the medium has a high flow velocity. liquids, above which the use of sleeves is absolutely recommended. The sleeves serve to protect the bellows and reduce its tendency towards oscillation induced by the flow, and to also reduce deposits and wear. The diagram “Guidelines for use of sleeves” shows the limit curves for steam, gas and The lateral expansion joints as a two pin system -M

Calculations Lateral expansion joint for movement compensation on one plane. ment capacity ± Δ zul is determined taking into account the nominal lateral movement capacity ± Δ lat as follows: System calculation Please note: As a result of the deflection of a lateral expansion joint, a bending moment and a force occur and load the anchors. The moment and force are caused by the bellows spring rate and by the friction in the hinges. The pressure thrust from the internal pressure and the effective cross section of the bellows are restrained by the hinged hardware. All formulae refer to a 50%...

Calculations The lateral expansion joints as a two pin system = anchor = pipe support/guide System calculation Lateral expansion joint for movement compensation in any direction perpendicular to its axis. All formulae refer to 50% pre-stressing of the pipe movement Δ1 and Δ 2, that must be compensated for, which means that the lateral expansion joint will be deflected in both, the pre-stressed and operating position by the amount of ± Δ / 2. Resulting movement Δ = √(Δ2+ Δ2) [mm] 1 2 Permissible movement capacity Following the recommendations explained in section “basic principals / nominal...

Calculations Forces at the connection points Fx = cr · p + clat · Δ1 + cz · p · Δ1 [N] 2 2 Fy = cr · p + clat · Δ2 + cz · p · Δ2 [N] 2 2 When the expansion joint types 7810, 7820 and 7850 (tied universal expansion joints with tie rods and washers) are used, the force cz · p · Δ / 2 does not occur. When the system is 50% pre-stressed, then the forces and the moments occur with different signs in the pre-stressed and operating position. Bending moments at the connection points Anchor/connection point forces Center to center distance between bellows and connection point [mm] Arc height [mm]...

Calculations Lateral expansion joints in three pin systems General The chapter “angular expansion joints” describes different three-pin expansion systems that comprise three angular expansion joints. If the center to center distance between the joints is short, it is often more economical to use one lateral expansion joint instead of the two angular units that are installed in tandem. The lateral expansion joints type 7710 and 7720, that are suited for movement compensation on one plane are suitable for the 3W, 3L and 3Z expansion systems. In 3 pin gimbal systems, the two gimbal joint can...

Lateral expansion joints for lateral movements on one plane Hardware design according to the manufacturing program.

Program Lateral expansion joints for lateral movements on any plane

Lateral expansion joints for lateral movements on any plane Special designs

Installation instructions Lateral expansion joints that allows a lateral movement on one plane only must be installed with a correct positioning of the tie bars with respect to the direction of the pipe expansion that is to be compensated for. The pipe movement must always be perpendicular to the axis of the pins. Pipe guides / supports In contrast to axial expansion joints, lateral expansion joints are less demanding with regards to pipe supports and guides. They have to support the weight of the pipeline including the insulation, flow, wind and other external loads in such a way that...