spring hangers,spring supports
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DESCRIPTIONSPRING HANGERS, SPRING SUPPORTS
SPRING HANGERS,SPRING SUPPORTS
VARIABLE SPRING ELEMENTS
Spring hangers, spring supports, sway braces ________________________2.1
Load table for spring hangers,spring supports and other spring elements __________________________2.3
Spring hangers, type 21____________________________________________2.5
Spring hangers, type 22____________________________________________2.6
Spring hangers (seated), type 25 ____________________________________2.7
Spring hangers (seated), type 26 ____________________________________2.8
Spring supports, type 29 __________________________________________2.9
Spring supports, type 28__________________________________________2.10
Angulating spring supports, type 20 ________________________________2.11
Spring hanger trapezes, type 79 __________________________________2.12
Sway braces, type 27 ____________________________________________2.13
Installation and operating instructions ______________________________2.15
Spring elementsTo compensate for slight vertical displace-ments in the piping, spring components areused as supports. The functioning of thesecomponents is based on preset helical coilsprings which exert a variable supportingload over the whole range of movementcorresponding to the given spring character-istics. Load variations resulting from this arelimited through corresponding specificationsbased on stress calculations for the piping -this depends on the sensitivity of thesystem.
The fundamental principles relevant for thefunction of the spring components are foundin the MSS SP 58 and VGB R 510 L guide-lines. See Technical Specifications, page 0.5.
LISEGA spring hangersVarious versions of spring elements, ideallysuited to whatever structural requirementsexist, are available. The optimum choicedepends on the installation situation.
Spring hangers, type 21This type, the one most frequently used, isfitted with an upper connection for suspen-
sion. It is installed whereverthe surrounding locationoffers a suitable connectionpoint and sufficientspace. The upperconnections can beuniversally adaptedwith standard com-ponents to any given
SPRING HANGERSSPRING SUPPORTS
Spring hangers, type 25This type is frequently used for
its simple installation, just sea-ting it on the existing steel. Theconnection is made by a rodpassing through the unit.
Spring supports, type 29If the installation location doesnot permit sus-
pension, then this model is asuitable alternative as aprop support. Where thereis considerable horizontaldisplacement of the supportload, and steel slides onsteel, lateral forces canunder certain conditionshave an adverse effect onthe operation of the sup-port system. To take precautionsagainst this, the use of PTFE bearings isrecommended. In this case the counter bea-ring should have a stainless steel surface.
Spring hanger, type 21
Spring hanger, type 25
Spring support, type 29
Type 29 with PTFEslide plate.
Recommended use of PTFE slide plates forspring supports type 29
To prevent constraints inthe system, thermalexpansion in the pipingand other piping compo-nents must not be hinde-red. The piping must there-fore be supported in a cor-respondingly elastic man-ner.
Angulating spring supports, type 20Unlike the spring support type 29,horizontal displacement can betaken up almost free of lateralforces by this design. This way that constraining fric-tional forces are completelyexcluded at all levels of move-ment, vertical and horizontal.
Sway braces, type 27These particular components act both intension and compression and are used tostabilize the piping and other plant com-ponents. An additional damping effect isobtained at the same time. The connectionparts correspond with those of ProductGroup 3.
With LISEGA sway braces, type 27, the following adjustmentscan be made:
load presetting free stroke installation dimension
See also Installation and OperatingInstructions, page 2.17
Load setting and blockingSpring hangers and supports are preset at theworks to the installation load and blocked inboth directions of movement. Blocking isnecessary to take up additional loads duringpickling, flushing, or hydrostatic tests. The factory settings are carried out on elec-tronically controlled test benches:
with spring hangers, values set at the factory are stamped onto a riveted nameplate.
the installation position is marked on the travel scale.
cold and hot settings are marked on the travel scale with a white and red sticker respectively.
the blocking device can be blocked in any position. The blocking pieces can be reinserted in any required position.
Spring hangers and supports should be setin such a way that the spring load and thepiping weight correspond with the cold loadposition.The corresponding hot load position resultsfrom the theoretically determined pipe move-ment (travel) and the spring rate.The load difference between the cold andhot positions acts on the piping as a reac-tion force and is limited by the relevantdesign specifications.
Generally, the max. permissible load devia-tion amounts to 25% of the operating load.
Above and beyond that, constant hangersexerting a constant supporting load over thewhole travel range are to be used.
Selection of spring hangersA decisive factor for the reaction force is thestiffness of the spring rate value of the res-pective coil springs. To cover the widest pos-sible field of application using spring han-gers, the load ranges are divided into 5 tra-vel ranges.
Please see Technical Specifications page 0.13for details of usage. See also the selectiontable, pages 2.3 and 2.4, as well asInstallation and Operating Instructions, page2.15.
Design related advantages
no welding (Types 20, 21, 27) fully galvanized surfaces specially prerelaxed springs integrated tightening devices adjustable blocking system variable connection possibilities TV suitability test a wealth of experience from over a
Angulating spring support, type 20
Sway brace, type 27angulated arrangement
Sway brace, type 27single arrangement
SELECTION CRITERIA FOR SPRING HANGERS AND SUPPORTS
Permissible force variationThe permissible force variation betweencold load (installation load) position tohot load (operating load) position islimited internationally by common speci-fications for pipe stress analysis to max.25% of the operating load.
Maximum working travelAdditionally, to preclude functionalimpairment due to instability from extralong springs, a working travel of maximum 50mmshould not be exceeded.
Spring ratesTo cover as wide a field of applicationsas possible while adhering to thesestandards, LISEGA spring elements aredivided into 5 travel ranges with cor-respondingly different spring rates.
Extra long springsTravel ranges 4 & 5 relate to extra longsprings and should only be used aftertechnical evaluation of the whole situ-ation, especially in sensitive pipingsystems.
Design typesThe selection of the suitable designtype depends upon the respective sup-port configuration or installation situ-ation.
Economical unit sizeTo find the most economical size, thefollowing procedures apply:
SELECTION OF SPRING ELEMENTS
Spring hangers type 21, Spring hangers type 25, Spring supports type 29, Angulating spring supports type 20
21 8. 1825 8. 1829 8. 1820 82 14
21 7. 1825 7. 1829 7. 1820 72 14
21 6. 1825 6. 1829 6. 1820 62 14
21 5. 1825 5. 1829 5. 1820 52 14
21 4. 1825 4. 1829 4. 1820 42 14
21 2. 1825 2. 1829 2. 1820 22 14
21 1. 1825 1. 1829 1. 1820 12 14
21 D. 1925 D. 1929 D. 1920 D2 19
21 C2 19
29 C2 19
Spring rate c (N/mm)
Working travel (mm)
21 9. 1825 9. 1829 9. 1820 92 14