Lateral Expansion Bellows

DESIGN & MATERIAL CONSTRUCTION

Design Pressure

16 Bar

Operating Temperature

-10C°/+350C°

DESCRIPTION

Lateral deflection is the relative displacement of the two ends of an Expansion Joint perpendicular to its longitudinal axis. This has been referred to as lateral offset, lateral movement, parallel misalignment, direct shear, or transverse movement. Hydraflex`s Tied-Lateral expansion joints are designed to absorb lateral deflection due to thermal expansion of the connected pipelines. Integrated liners minimize contact between the inner surface of the bellows and the fluid to hold friction losses and provide a smooth flow. Stainless steel bellows (membranes) are designed according to EJMA coding system and manufactured acc. to European Standard EN 14917:A1. High grade bellows & inner sleeve material provides high durability, remarkable column, and in-plane instability properties at elevated temperatures. T-Lat type expansion joints are finished Van stone end configuration for swivel flanges provides complete stainless-steel surface which is in contact with the fluid. Stainless steel flanged version provides high corrosion and temperature resistance up to 550°C.

APPLICATIONS

- Low, Medium & High Temp. Heating systems.
- HVAC-R mechanical piping systems.
- Building separation (dilatation) points.
- Steam & condensate pipelines.
- Industrial Process & Applications.
- Fire Protection Piping Systems

QUALITY

All “T-Lat” type expansion joints are produced by fully penetrated TIG welding method Acc. to Hydraflex’s approved WPSs. Design “T-Lat” is type approved by hydrostatic pressure test @1.5 times of the design pressure. PED 2014/68/EU approval and material certificates acc. to EN 10204 is available for all sizes on request.

- T-Lat type of expansion joint are designed to absorb lateral deflections in all planes.
- Tie rods to continuously restrain the full bellows pressure thrust during normal operation while permitting only lateral deflection.
- Minimum application area in comparison with pipe loops.
- Long service life, easy installation, and maintenance.

IMPORTANT

Tied Lateral expansion joints restrained type expansion joints and the nuts on the items must not be loosen in any case to use them for absorbing axial deflection. We strongly advise not to use of expansion joints to handle the piping misalignments.

IMPORTANT TYPE DESIGNATION

INSTALLATION INSTRUCTIONS FOR AXIAL EXPANSION JOINTS

- Store in clean dry area where it will not be exposed to heavy traffic or damaging environment.
- Care shall be exercised to prevent any damage to the thin bellows section, such as dents, scores, arc strikes and weld splatter.
- No movement of the Expansion Joint (compression, extension, lateral offset, rotation) due to piping misalignment shall be imposed.
- Any field pre-positioning shall be performed in accordance with specific instructions which include both the direction and magnitude of movement.
- It is good practice to leave one flange loose until the expansion joint has been fitted into position. Make necessary adjustment of loose flange before welding.
- Anchors, guides, and pipe supports shall be installed in strict accordance with the piping system drawings.
- The Expansion Joint, if provided with internal sleeves, shall be installed with the proper orientation with respect to flow direction.
- Once the pipeline anchors or other fixed points are in place, the piping is properly supported and guided and the Expansion Joint installed, the shipping devices should be removed in order to allow the Expansion Joint to compensate for changes in ambient temperature during the remainder of the construction phase.
- Do not use chains or any lifting device directly on the bellows or bellows cover.
- Do not force-rotate one end of an expansion joint for alignment of bolt holes. Ordinary bellows are not capable of absorbing torque.
- Do not use cleaning agents that contain chlorides.
- Do not use steel wool or wire brushes on bellows.

PIPE SECTIONING

No more than only one expansion joint must be installed between two main anchors. If the thermal expansion of the pipeline is too big to be handled by single expansion joint, pipeline should be divided in sections by additional intermediate anchors.

ALLOCATING THE EXPANSION JOINTS

If possible, expansion joints are advised to be located as close as possible to one of the anchors to prevent buckling risk. Hydraflex, Spring Lane, Northampton NN1 2JW hydraflex.co.uk Sliding guides & anchor allocations should be completed as shown below, L4 &L5 values should be selected from the

CONNECTING THE EXPANSION JOINTS

The attachment edges of the pipe should be smooth, clean and parallel to each other. Don`t use bellows to correct for misalignment of piping unless this has been considered in the
design of the expansion joint.

Counter flanges should be placed vertically to the pipe axis.

Using the proper electrode, weld the expansion joint to adjacent piping. Damages caused by arc sparks through welding process should be prevented. Bellows must be protected by a wet towel or cloth during the welding

Orient expansion joint flanges so that the bolt holes are aligned with the mating flanges

Do not torque the expansion joint to match the bolt holes of the mating flange. This causes torsion on the bellows and will severely reduce the bellows capability during operation and may lead to premature failure of the expansion joint.

INSTALLATION INSTRUCTIONS FOR AXIAL EXPANSION JOINTS

Standard axial expansion joints are unrestrained expansion joints. So, fixed points should be created as to withstand springing force and the pressure thrust.

CALCULATION OF ANCHOR (FIX POINT) LOADS

PRESSURE THRUST:
Pressure thrust is the most important force encountered in pressurised pipe systems and if ignored or incorrectly calculated, it can have a major impact on the pipe systems and the anchors. Pressure thrust can`t be eliminated as long as the axial bellows movement exist in the pipeline, and it must be calculated very carefully. Bellows usually have a cross-sectional area, which is slightly larger than the pipe diameter due to the height of the convolutions.

This is very important as it should be taken into consideration when designing the fix points. The effective cross section is given by the sketch below. Pressure thrust force is calculated by bellows mean diameter multiplied by the maximum system pressure as follows: (always use maximum pressure that occurs, usually the test pressure)

Fp = P x A
Fp = Pressure thrust force [N]
P = Pressure [bar]
A = Bellows mean diameter area [mm2]

SPRINGING FORCE:
Flexible bellows can be compared to a steel spring in its flexible motion. The spring rate is an expression of the force required to compress
or extend the bellows, or alternately its resistance to deflect, which is another factor to take into account when calculating loads on fix points.
The amount of the spring force is dependent on the bellows spring rate and the amount of the bellows movement, which is calculated as follows:

F = K x X
F = Force [N]
K = Spring rate [N/mm]
X = Movement [mm]

IMPORTANT:

If you are working with the installation of unrestrained expansion joints with no built-in restraining hardware like tie rods, hinges gimbals etc... Fixed points should be created as to withstand springing force and the pressure thrust. We strongly advise not to use of expansion joints to handle the piping misalignments.

POST INSTALLATION INSPECTION PRIOR TO SYSTEM PRESSURE TEST

A careful inspection of the entire piping system shall be made with particular emphasis on the following:

- Are anchors, guides and supports installed in accordance with the system drawings?
- Is the proper Expansion Joint in the proper location?
- Are the Expansion Joint flow direction and pre-positioning correct?
- Have all of the Expansion Joint shipping devices been removed?
- If the system has been designed for a gas, and is to be tested with water, has provision been made for proper support of the additional dead weight load on the piping and Expansion Joint? Some water may remain in the bellows convolutions after the test. If this is detrimental to the bellows or system operation, means shall be provided to remove such water.
- Are all guides, pipe supports and the Expansion Joints free to permit pipe movement?
- Has Expansion Joint been damaged during handling and installation?
- Is Expansion Joint misaligned? This can be determined by measuring the joint overall length, inspection of the convolution geometry, and checking clearances at critical points on the Expansion Joint and at other points in the system.
- Are the bellows and other movable portions of the Expansion Joint free of foreign material