C. L. Engineers

This type of elbow pressure balanced expansion joint is really a combination of several types. Its purpose is to retain and balance the pressure thrust so that main anchoring of the pipe or adjacent equipment is not required, and forces and movements on attachment flanges of delicate equipment, such as turbines, are kept to acceptably low levels.

Briefly, the deflections to be accepted are handled by the proper type of expansion joint, which normally, and as shown in the above sketch, is a tied universal type to accept lateral movements. However, the pressure balanced elbow is usually required because axial deflections are also present. In order to accept these movements, a bellows is added beyond the elbow with the same cross-sectional area as the ones in the universal section.

The gimble expansion joint is bassically the same as the hinge type ,except that insteade of being limited to deflection in only one plane, it can accept bending or angulation in any plane .It contains two sets of hinge pins or pivots,the axis of each set perpendicular to the other . Each set of pins is connected to each other with a central gimbal ring, in much the same way that a universal joint on an automobile works

Features:Absorbs angular rotation
              Eliminate pressure thrust forces
              Transmit external loads
              Minimum guiding required
              Prevent torsion on bellows
              No main anchors required
              Low forces on piping system

These Hinged expansion joints contain hinges or pivots which cause the unit to bend in a single plane. Normally these units are prevented by their design from deflecting axially, either in extension or compression. Their hinge mechanisms are usually designed to accept the full pressure thrust. Also, because of the hinge mechanism's design, shear loads, such as from the weight of adjacent piping, can be accepted by this expansion joint, relieving the piping designer of having to provide additional supports and anchors required by the Single type.

Our  metallic expansion joints are highly useful in absorbing movements caused by thermal changes. By controlling these changes, the flexible joints of metallic expansion joints help in providing relief in ducting systems.Metallic expansion joints,besides acting as selection of a pipe,capable of withstanding the design temperatures,pressures and media,also provide the flexibility that makes them necessary.The flexibility can be either axial,lateral or angular.In many installations rigidity of is needed to support piping loads or to control the motion of the bellows and the pipe.Features are added to the expansion joints to limit the degree of freedom or the types of deflections and to resist shear or tension or compression loads and/or bending moments.
  In addition to this, these also perform the function of vibration isolation, shock absorbing and also compensate minor misalignments of adjoining ducting or equipment. Depending upon the design, these  metallic expansion joints are made of various materials such as:

• SS AISI 321/316/304/310
• NICKEL ALLOYS
• BRASS/COPPER

This single expansion joint is simply a bellows element with end connections. Regardless of accessories, such as liners and covers, it will deflect in any direction or plane that the bellows will. It is the least expensive type, but requires that the piping be controlled as to the direction of the movements required of the unit. 

The expansion joint should not be expected to control the movement of the pipe. If the piping analysis shows that the expansion joint must accept axial compression, then the piping must be guided and constrained so that only that movement will occur. 

This expansion joint will not resist any deflections with any force other than the resistance of the bellows, which is a function of the spring rate times the deflection amount. It is incapable of resisting the pressure thrust along its axis, which is the product of the pressure times the effective, or cross sectional, area of the bellows.

The universal expansion joint consists of two bellows separated by a pipe section or spool. The primary purpose of this arrangement of universal expansion joint is to have a unit which will accept large amounts of lateral deflection. The amount of lateral deflection they can accept is a function of the amount of angulation each bellows can absorb and the distance between the bellows. For a given bellows element, the amount of lateral deflection capability can be increased or decreased by simply changing the length of the center spool. In this catalog three standard overall lengths are given with their lateral movement capability. If the piping problem requires greater capability, then the overall length can be increased to suit.