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05-10-2009, 11:15 PM
ပုိက္လုိင္းတစ္လုိင္းဆုိၿပီး အထင္ေတာ့ မေသးလုိက္ပါနဲ႔။ သူရွိမွ လုိအပ္တာေတြ ေရာက္ရွိမွာမုိ႔ pipe support ေတြက အေရးႀကီးပါတယ္။ Strength ေတြေသခ်ာထည့္တြက္ရမွာမုိ႔ Design ေကာင္းေလ ေငြကုန္သက္သာမွာျဖစ္ပါတယ္။

ေနာက္က်ရင္ tiltle ေတြကို စာသားျဖည့္သြားပါမယ္
CSD = Contractor Standard Drawing
ပုံေတြကိုလည္း ျဖည့္ေပးသြားပါမယ္...Forum ကို ေသခ်ာမသုံးတတ္ေသးလုိ႔ပါ..သုံးတတ္ေအာင္ေမႊေတာ့မယ္ေနာ္ ;D

This manual covers the general requirements for arrangement, selection and design of pipe supports for process plants for LNG plants.
This manual does not cover the structural supports to be designed by civil and architectural groups.


The requirements contained in the latest edition of the following codes and standards shall form a part of this specifications.
2.1 Code
(1)ASME B31.3 - Process Piping
(2)ANSI/API RP 520 - Sizing, selection , and installation of pressure relieving device in Refineries Part II
(3)BS 5500 -Unfired Fusion welded pressure vessels
2.2 Contractor Standards
(1)CSJS- 05001 E Piping Design
(2)CSJS- 05002 E Piping Flexibility Analysis
(3)CSD 4100-700 Pipe Supports
(4)CSJS-SD-030-14 Typical detail of Miscellaneous Foundations
(5)CDP L 3009 E Pipe Rack Loading Data Preparation Procedure
(6)CDP L 3011 E Preparation Manual for Civil & Structural Information Drawing
(7)CDP L 3010 E Preparation Manual for Equipment Information Drawing
(8)CDP L 4003 E Drafting Manual for Pipe Support drawing
(9)CDP L 4004 E User Manual for Special Pipe Support Drafting System
(10)CDP L 3004 General Procedure for Piping Flexibility Analysis

3.Basic Design Laod Requirements
3.1 Design Loads
Design loads for pipe supports shall be included in the following loads.
3.1.1 Operation Loads
(1)Piping Component Weight
(2)Fluid Weight (*1)
(3)Thermal Insulation Weight
(4)Thermal Forces
(5)Friction Forces
(6)Discharge Blow-off Forces of Pressure Safety Valves
*1: For Liquid service piping, density of 1.0 shall be applied for 8" and smaller and density of service fluid for 10" and larger.

3.1.2 Testing Loads
(1)Piping Component Weight
(2)Full Water Weight(*2)

*2: Full water weight shall be calculated as follows:
(a)Where 2 or more lines are arranged on the same support, weight for the bigger line shall be taken.
(b)When 2 or more lines are to be tested simultaneously, sum of them shall be taken.
(c)When piping is tested pneumatically, full water weight need not be considered.

3.1.3 Other requirements based on Project Specification
(1)Wind load
(2)Seismic load
(3)Vibration load for reciprocating pumps/compressors and two-phase flow piping
(4)Impact load due to Hydraulic shock
(5)Maintenance Load when Additional Loads are anticipated

3.2 Supporting Spans
Piping shall be supported at the points within supporting span as shown in CSD 4100-700 as follows:
(1)Support spans for ANSI Pipes Sheet No. 4
(2)Support spans for JIS Pipes Sheet No. 6
(3)Calculation Basis of Support Spans for ANSI Pipes Sheet No.6
(4)Calculation Basis of Support Spans for JIS Pipes Sheet No.7A
(5)Support Spans at Corners Sheet No.7B

3.2.1 Maximum spans shall be limited so that the bending stress due to piping weight shall not exceed 60% of the basic allowable stress at its design temperature unless otherwise specified.

3.2.2 For thin wall pipe, high temperature piping (above 350 degree C)and non-ferrous/non-metallic piping, support spans shall be calculated in accordance with CSD shown above.

3.2.3 As shown in CSD above, support spans shall be limited so that the maximum deflection does not exceed 26.4 mm or 1/4 of nominal pipe diameter, whichever is smaller.

3.2.4 Support spans for vertical piping shall be 1.5 times of spans for horizontal run as show in CSD, unless otherwise stresses due to wind or earthquake force exceed the allowable stress.

4. Materials

4.1 Pipe support materials shall be ASTM A36 or equivalent in principle, equivalent materials to mother pipe shall be used for attachments on alloy steel materials, or parts to be exposed to high temperature.
4.2 For stainless steel piping, only stainless steel plate, sheet or shapes, or plastic or rubber sheet shall be used for support material to be contacted with or attached to the piping. Galvanized steel shall not be used for this purpose.
4.3 Allowable stresses for support materials shall be in accordance with ASME B31.3. Correction Factors for Tension and Sharing stress shall also comply with the Code.
4.4 Kinds and Sizes of support materials shall be minimized.

5. Information For Supports

When pipe supports are installed on equipment shell, concrete structure, steel structure to be fireproofed or on the ground, information for the location, load, etc., shall be sent to the relevant departments in
accordance with the following procedure and manuals.
(1)CDP L 3009 E Pipe Rack Loading Data Preparation Procedure
(2)CDP L 3010 E Preparation Manual for Equipment Information Drawing
(3)CDP L 3011 E Preparation Manual for Civil & Structural Information Drawing

U-Bolts For restriction of movements other than axial movements of piping, or fixing small bore piping by tight setting
Adjustable Bolts For adjusting horizontal and/or vertical position of piping for the alignment or setting clearances accurately
Pipe Clamps For clamping of pipe for hanging or resting on supports without welding attachments to pipe
Lug Plates For setting pipe supports on equipment shell without welding onto the shell directly.
Base Plates For placing pipe supports on pavement, foundation, floor, etc.
Sliding Pads For reduction of friction forces at sliding plates of pipe supports
Insert plates For setting pipe supports substaining more than 1.0 ton or vibratoin/shock forces on concrete structure and steel structure to be fireproofed, by welding
Expansion Anchor Bolts (=< 1 ton) and Chemical Anchor bolts(>1 ton)
For setting supports on pavement, foundation or concrete structure.
Expansion anchor bolts shall be used for substaining shock/vibration forces or 1.0 ton or less of pulling load as shown in Section 3.7,CDP L 3009 E.

7.1 General
7.1.1 Pipe supports sustaining the weight shall be arranged in accordance with the supporting spans as shown in CSD, at the location incorporated to flexibility analysis and at the span against mechanical vibration due to reciprocating pumps and compressors.
7.1.2 Anchors, guides, stoppers,etc., shall be installed as required for piping flexibility, restriction of movements, vibration, dynamic forces such as PSV discharge blow-off forces and hydraulic shock at the supports described above or additional supports as required.
7.1.3 Limit stop type supports shall be installed where some limited movement need to release for stopping movements without over-stress, vibration or dynamic forces.
7.1.4 Where vertical movements are anticipated at pipe supports due to thermal expansion and settlement of piping, equipment or supporting structure, the following consideration shall be required.
(1)Resting type supports can be used when vertical movement do not cause rise-up of piping from supports or over-stress.
(2)Resting type supports with guides or stopper shall be used when piping will rise up from supports but it will not cause excessive stresses/moments on piping and the connected equipment nozzles.
(3)Spring supports shall be used when piping will rise up or supports and it will cause excessive stresses/moments on piping and/or the connected equipment nozzles. (Refer to Section 10.1)
(4)For large bore piping for pump suction and discharge, in particular in unpaved area, the first supports shall be installed on the common foundation with the pumps.
Fig 7.1.4(a,b,c)

7.1.5 Pipe Supports shall preferably be positioned on piping as follows:
(1)On pipe rather than valves, flanges, fittings,etc. welding attachments on bends shall be minimized.
(2)On piping section which do not require frequent removal or disconnection for decoking, regeneration, cleaning or isolation.
(3)As close as possible to heavy components such as PSV, valves in particular for high pressure rating and control valves.
(4)At the positions where the vertical movements are negligible small.
(5)At the position close to flanges that piping will be bent down or deformed when the flanges are disconnected for maintenance.

7.1.6 Where reduction of friction forces is required for sensitive equipment such as pumps and compressors, saving foundation volume, etc., suitable size or sliding pads shall be used with the relevant supports incorporated to flexibility analysis. Friction factors for combinations or contact surfaces shall be based on CSJS-050 02 E. Section 6.3.1.

7.1.7 Auxiliary supports shall be installed as standard or special supports for reinforcement of structural members which pipe supports are installed. Torsional forces/moments shall not be sustained by a single beam or column for structures and shall be converted to bending forces/moments on multiple structure members.

7.2 Selection of Pipe Supports
7.2.1 Pipe supports shall be selected in consideration of piping configuration, position of piping, supporting point or conditions, pipe sizes, etc., by the following procedure.

7.2.2 Standard type supports shall be selected as maximum extent. Combination of two or more types of standard supports, for example bracket type support, dummy pipe and U-bolt shall be preferred.

7.2.3 Spring supports shall be installed independently or in combination with some supports as required by flexibility analysis.

7.3 Pipe Rack and Sleeper Piping
7.3.1 Anchor points shall be assigned for each straight section of pipe rack and sleeper piping regardless of line temperature. The position of the points shall be determined taking into account piping flexibility, movements of piping and restriction of dynamic or reaction forces. Axial movements of piping shall be minimized at the following areas.
(1)Process unit battery limit
(2)Piping around pumps to be connected
(3)Piping near crossing pipe rack or sleeper

7.3.2 Guides shall be arranged subsequent to arrangement of anchors. Long straight piping shall be guided against lateral movements due to thermal expansion including solar radiation, water hammer, etc,. The following interval shall be applied for guides unless otherwise the longer or shorter interval is required for flexibility analysis including wind, seismic loads.
Pipe Size Approx. Guide Spans
=< 1-1/2" 6m
2"=<6" 12m
8"=<16" 18m
=>18" 24m

7.3.3 For guides around corner of pipe way, lateral movements of piping due to thermal expansion shall be checked, and when necessary limit stoppers with suitable clearances shall be installed in place of guides.

7.3.4 Small bore piping shall be grouped together and when span of the rack or sleepers is longer than standard supports spans for them, these shall be supported in between.

7.3.5 For large bore piping on RC pipe rack, at least 25mm height of spacer shall be installed at the main beams for avoiding contact with the intermediate beams when no load on intermediate beams for certain lines is informed by civil and structure group.

7.3.6 Thermal movements shall be reflected to supports as follows:
(1)Length of pipe shoes
Length of the shoes shall be long enough to the axial movements under operating temperature. The shoes shall rest on the supports at least 75 mm from the centerline of supporting beam after sliding. The length of the shoes shall be increased in or the shoes shall be installed in off-center when piping movements are larger than 75mm.
Fig 7.3.6(A)

(2)Space of Pipe Rack or sleepers
Around the corner of pipe way, space for lateral movements due to thermal expansion shall be provided adequately.
Fig 7.3.6(B)

(3)Supports for branch Piping
Branch piping from long run header shall not be fixed at the rack or sleepers except that the movements of the header at the branches are small enough.
Fig 7.3.6(C)

7.4 Riser piping along with Equipment and Structure
7.4.1 Weight of riser piping shall be sustained at the highest supports with down steppers except for special case. For piping along with equipment, the supports shall be as close as possible to level of the nozzle to be connected.

7.4.2 Number of supports on equipment shell shall be minimized in particular on low alloy steel shell. Where structures are installed along with the equipment, the supports shall be installed on structure but not on equipment.

7.4.3 When the riser piping has horizontal run in between, the weight supports shall be installed in each vertical section in principle.

7.4.4 Guides shall be installed for the span as shown in Section 3.2.4.

7.5 Centrifugal Pump and Compressor Piping
7.5.1 Position and restraint conditions of supports for Pump and compressor piping shall incorporate into flexibility analysis. When the friction factor of 0.1 is indicated in the calculation, suitable sliding pads shall be used at the positions.

7.5.2 Adjustable supports shall be installed as the first and when necessary, second support from pump or compressor nozzles for the piping alignment work. When spring supports are installed around the equipment, adjustable supports shall be independently installed for the aligment purpose.

7.5.3 Where vertical section of piping near the nozzles tend to incline when piping is disconnected from the nozzle, adjustable support shall be additionally installed in the vertical section for alignment purpose. The adjustable bolts shall be released after the alignment when thermal movements of piping will be restricted by these bolts. (*3)
*3 Support drawing shall indicate caution sign as follows:
Fig 7.5.3

7.5.4 For large bore or alloyed steel and high temperature piping ,effective supports shall be installed for reducing the reaction forces /moments on equipment nozzle by stopping lateral forces due to thermal expansion.The provision shall incoporate into flexibility analysis. Major parts of the supports shall be designed by civil and architectural group.
Fig 7.5.4

7.5.5 When the spring supports are used around equipment, suitable guides or limit stoppers shall be additionally installed, preferably at the neutral point of thermal movements, against vibration due to fluid flow, valve operation torque, wind , earthquake,etc.
Fig 7.5.5

7.5.6 Potential hydraulic shock on discharge piping at the following service pumps shall be stopped by suitable anchors or stoppers providing around the pumps.
(1) shipping pumps
(2) circulating water for seawater pumps
(3) other similar service pumps
Fig 7.5.6

7.5.7 When the expansion joints are used at the pump nozzles support with stoppers and sufficient size of foundation shall be installed next to the expansion joints to protect pumps from pressure thrust. Allowable forces and moments shall be confirmed with mechanical engineer.

7.6 Reciprocating Pump and Compressor Piping
7.6.1 Suction, discharge and spill back lines for the pumps and compressors shall be supported by steel supports (for pumps) and sleepers or concrete beam(for compressors)which are located at spans for prevention

of resonance as per Attachment-A(Later)
7.6.2 At least a support shall be installed on each straight section of piping in principle except that a change of direction may be contained between the supports where the straight section is within approx. 10 times pipe

Fig. 7.6.2
7.6.3 Each support shall be restraint type to stop vibration forces. Limit stoppers shall be installed for releasing some lateral movements as per flexibility analysis.
7.6.4 Compressor piping including utility piping connected to compressors shall be supported from grade and not be supported from any members of compressor shelter.
7.6.5 When pulsation analysis is required for compressor piping, location and performance of pipe supports shall be decided on time in the basis of the support span shown in Section 7.6.1 and reflected by the analysis

report. Changes from the basis of analysis shall not be accepted.

7.7 PSV and Control Valves for High Differential Pressure
7.7.1 In/Outlet piping for PSV shall be supported as close as possible to PSV to sustain discharge blow off forces/moments as well as the weight.
Fig 7.7.1
7.7.2 In/outlet sides of high differential pressure control valves shall be supported rigidly to sustain tile reaction forces and prevent the piping from vibration in addition to the weight. Dummy pipe,lugs, pipe shoes, etc.

shall be eliminated and clamps or halves to be welded onto piping shall be used as the attachments.
Fig 7.7.2
7.7.3 These supports shall have sufficient strength and mass against thrust forces and vibration.

7.8 Two-Phase Flow service Piping
7.8.1 Vibration forces acting on each corner of piping shall be sustained at or near corners by guides, limit stoppers or anchors. Limit stoppers shall be preferably used to restrict the vibration by kick-effects for high

temperature piping.
Fig. 7.8.1

7.8.2 When limit stoppers are not applicable because of large movements, variation of movements in different operation mode or difficulty of rigid supports, vibration dampers shall be used. (See section 10.2)

7.9 Piping with Expansion Joints
7.9.1 Both ends of piping of expansion joint shall be fixed by anchors or stoppers to sustain pressure thrust and friction forces except that tile end point is nozzle.
7.9.2 Guides shall be installed at the both sides of expansion joints required preventation of undue lateral movements, in particular around the joints.
7.9.3 Typical arrangement of anchor, guides and stoppers for piping around expansion joints shall be as illustrated as follows.
(Fig 7.9.3 မွာ ပုံေတြျပထားပါတယ္)

05-24-2009, 11:08 PM
8 Selection of Standard Pipe Supports
8.1 Selection Procedure
8.1.1 Elements for selection
The following items are required for selection of standard supports from selection tables in CSD 4100-700, Sheet No.3A through 3G.
(1)Parts of piping to be supported
Example; Horizontal pipe with or without insulation
Vertical pipe with or without insulation
Side or bottom of elbows or tees
(2)Portion which pipe support is installed
Example; Grade, foundation or concrete floor
Steel column or beam-top, side or bottom
Concrete column or beam-top, side or bottom
Equipment shell
(3)Height or distance between piping and installation point
(4)Pipe size and number
(5)Load to be supported
Example; vertical loads
Horizontal forces to be sustained by stoppers or guides
(6)Approx. length of piping to be supported or the anticipated weight
(7)Anticipated thrust forces and the direction to be supported

8.1.2 Work Steps
Types and sizes of standard supports shall be selected by the following work steps shown in Table 8.1.2.
Table 8.1.2 ကိုဓာတ္ပုံရုိက္ယူထားရန္
8.2 Standard Pipe Shoes
8.2.1 The pipe shoes shall be selected from CSD for insulated lines, heat trace and large bore piping. For 1-1/2" and smaller piping, pipe shoes shall be used the pipe rack, stanchions or sleepers in principle.
8.2.2 Height of the shoes shall be selected from CSD. When insulation thickness is thicker than 120 mm, the height shall be increased in.
8.2.3 The standard length of the shoes shall be as per CSD. The longer shoes shall be selected for the following cases.
(1)Total dimension of width of stoppers and supporting beam exceeds 300 mm,when anchors or line stoppers are installed.
Fig 8.2.3-1
(2)Axial movement is more than 76mm and no offset. (See section 7.3.6-1)
8.2.4 The shoes shall be used for sloped piping on pick rack or sleeper to adjust the height by cutting. Shim plates may be used to complement further adjustment.
Fig 8.2.4
8.2.5 When PTFE sliding pads are to be attached to the shoe, temperature at slide plate of the pipe shoe shall be lower than 100 degree C as possible. In case the temperature exceeds 100 degree C, one of the

following provision shall be required.
(1)Increase in the shoe height
(2)Insulation or installation block (commercial type) between the sliding pad.
Remark: Elevation of piping shall be reflected to the thickness of insulation block.
(Fig 8.2.5)
8.3 Anchors, Guides and Stoppers
8.3.1 Anchors shall be used to stop the piping movements in X,Y and Z directions. Restriction of the rotation in any directions shall be made by installation of guides at the both sides of anchors.
8.3.2 U-bolts shall preferably be used as guides for small bore piping and non-insulated piping relaively short run.
8.3.3 U-bolts for non-insulated piping or guides for insulated piping shall be installed on each support in the area which bouyancy due to oil or water pool, or wave attack on piping are anticipated.
(Fig 8.3.3)

8.4 Fixed and Slide Type Supports
8.4.1 Except for Type-11 of standard supports in CSD, the standard supports are axially or laterally-free construction. When guides are necessary for stability of piping against vibration, valve operating torque, water

hammer, etc., suitable type of guides or U-bolts shall be selected from CSD and assigned in combination with the resting type supports.

8.4.2 When valve sets, flow meter sets, control valve sets, etc. are supported, only one side of supports shall be the fixed, and others shall be slide types. Assignment of the fixed type supports shall incorporate to piping flexibility analysis.
(Fig 8.4.2)

8.5 Reinforcement for large bore piping
8.5.1 Support points of large bore piping in horizontal run shall be reinforced against the local stress in accordance with CSJS-050 01 E, Section 12.3(6).
8.5.2 The local stress shall be checked in accordance with BS 5500 Annex G 3.3 when pipe wall thickness, supporting span, fluid weight are critical and/or to be optimized.
8.5.3 Strength of pipe shoes (or saddles) for above mentioned service shall also be checked by Bijlaard formula. Width or angle of the shoes shall be increased in, when necessary.

9. Design of Special supports
9.1 Common requirements
9.1.1 Numbers of types of the special supports shall be minimized and these shall be simple as possible. Special type supports typically used shall be in accordance with CDP L 4004 E.
9.1.2 Configuration of standard supports shall be adopted as the maximum extent as parts of support, and the standard components such as guides, stoppers and base plates shall be used as possible.
9.1.3 The supports shall be so designated that the following requirements are satisfied.
(1)Dimensional adjustability at job site
(2)Ease of fabrication and installation (Simple design)
(3)Proper strength at each components and the welds against the loads
(4)Proper clearance or freedom for thermal movements or expansion
(5)Welding construction except that bolting joints shall be applied for members to be removable & disconnect of piping, and to be connected on lugs on equipment.
9.1.4 Minimum headroom clearance of the support members shall be 2.1 m when the supports are installed on access area.
9.1.5 When pipe is used as support members a 6mm diameter of drip hole shall be provided at the lower portion of each pipe.
9.1.6 For bracket or box type supports, clearance for thermal expansion of pipe in diagonal shall be provided as required.
(Fig 9.1.6)
9.1.7 When trunnion pipes are attached on schedule 20 or thinner and 16" pipe, tile trunnion shall be installed on reinforcement pad which has at least the same thickness as mother pipe.
9.1.8 When pads or reinforcement pads are installed, the following provision shall be considered.
(1)Pads shall be equivalent material with the mother pipe.
(2)Corners of the pads shall be rounded at least 30 mm radius.
(3)A 6mm diameter of drilled hole shall be provided on each pad.
(4)Pads shall be welded continuously to mother pipe.
(Fig 9.1.8)
9.1.9 Trunnion, dummy pipe, pads, etc. shall not be attached on welds on piping. Welds for them shall be at least 5 times the pipe thickness away from welds on piping. When interference with the longitudinal welds of

piping is not avoidable, interruption of weld shall be required at the crossing point.
(Fig 9.1.9)
9.1.10 Shape steel shall be oriented in stronger axis to sustaining loads and together the strength of them are uniformly transferred. Rib plates shall be used when required.
(Fig 9.1.10)
9.1.11 Edges of plates such as spacer plates to be installed at 2.1 m or lower form grade or platform shall be cut or ground smooth for safety. Support detail drawings shall show it clearly.
(Fig 9.1.11)

9.2 Strength of Supports
9.2.1 Similar sizes of steel members shall be used for the supports referring to similar size of standard supports without the calculation when the loads and the dimensions are not in special.
9.2.2 Strength of the support members shall be calculated or checked as follows;
(1)Support members shall be calculated and selected by Special Pipe Support Drawing System, CDP L 4004 E.(See section 7.2.1)
(2)Strength of anchor bolts (bars) shall be checked when acting forces result large sharing and/or tension stress. Pulling load on expansion anchor bolts shall be evaluated. (See section 6.2)
(3)Sharing stress at welds and attachments on pipe shall be checked when the points are exposed to relatively large forces and/or high temperature 70% of welding efficiency shall be considered for the

strength of field welds.

9.2.3 Supports for PSV for liquid service shall be designed against the reaction forces calculated as follows.
(1)Blow-off Forces at open end (open system) Refer to Section 2.4.1, ANSI/API RP 520, Part-II.
(2)Blow-off forces at elbows (Closed system)
9.2.4 Exciting forces of two-phase flow piping shall be advised by specialist based on the pipe dimensions, flow rates of liquid and vapor, density and molecular weight, and temperature.
9.2.5 Supports for reciprocating pump and compressor piping shall be designed against pressure thrust forces calculated as follows.
F= 2 (a) (P) (S)
where, F= Pressure thrust force, kg
2= Connection factor for impulse flow
a= Pulsation factor to be specified (*4)
P=Design pressure of piping, kg/cm2
S=Cross sectional area of piping, cm2
*4 Compressor data sheets shall be referred to pulsation factor.

9.2.6 For universal type expansion joints, thrust forces acting on the anchors shall be calculated as follows. (See Fig 9.2.6)
F= Fp+Fs+Ff1+Fs2
Fp= (A) (P)
Fs= (d) (S)
Ff1 or Ff2 = (Pipe Weight between anchor point and expansion joint) (Friction Factor)
F= Total vectorial force on anchor, kg
Fp= Vectorial force due to internal pressure in expansion joint, kg
Fs= Vectorial force due to deflection of expansion joint, kg
Ff1= Vectorial Force due to Friction of piping between expansion joint and anchor point , kg
Ff2= Vectorial Force due to Friction of piping between anchor point and next expansion joint,kg
A= Effective area of expansion joint, cm2
P= Internal pressure of piping, kg/cm2G
D= Deflection of Expansion joint, compression (+) or Tension (-),mm
S= Spring constant of expansion joint, kg/mm

9.2.7 Wind forces shall be calculated in accordance with CSJS-050 02E Sec.6.3.2, where supports for 20" (NPS) or larger piping is installed at 20m or higher.
9.2.8 When seismic design is requested by job specification, the supports shall be available to the horizontal forces in 2 directions. The forces shall be calculated as the product of seismic factor and weight of piping

including fluids and insulation to be supported.

9.3 Pipe Supports against Shock and Vibration
9.3.1 Flare header shall be guided close to the elbows or tees against the large lateral movement or falling-down due to the hydraulic shock. Box type supports with guides or limit stoppers are Preferable.
(Fig 9.3.1)

9.3.2 Vibration-cut supports shall be used on sleepers or concrete beams for reciprocating compressor piping to stop the vibration forces and allow the axial thermal movements, as required. When lateral movements

are necessary to release, the suitable size of slot holes shall be provided on the vibration-cut supports.
(Fig 9.3.2)

9.3.3 Welding attachments on reciprocating compressor piping shall be minimized as possible. When unavoidable, the welds shall be continuous to pipe smooth and none of notches.

9.3.4 Supports against any vibratoin forces shall have ample strength and connected on the foundation or supporting structures tightly.

9.3.5 When vibration is anticipated on cement lined piping at butterfly valves due to occassional throttled operation, support shall be installed close as possible to the valves to anchor the pipe approx. 3 times or piping

weight to be supported should be provided on the foundation.

9.4 Stiffeners for vacuum service piping
9.4.1 Stiffeners shall be installed at the intervals calculated in accordance with ASME B31.3 Section 304.1.3. The material shall be suitable to the design temperature.
9.4.2 Stiffeners shall preferably be installed at the positions of the weight and/or guide supports.
Fig 9.4.2
9.5 Adjustable Type Supports
Adjustable bolts shall be provided on the following supports.
9.5.1 Supports around centrifugal pumps and compressors for alignment of the piping in horizontal and/or vertical before connecting to the nozzles.
9.5.2 Supports which the accurate clearances for guides or limit stoppers are required for the flexibility, against vibration, etc.
Remark: Accurate clearances are difficult to be obtained by welding work at fabrication and installation of supports.

9.6 Braces for Small Branches
9.6.1 Braces shall be installed at small branches such as drain, vent, instrument connections except for temperature instruments, sample connections and other valved branches to protect welds for the branches from

bending and fatigue for the following service piping.
(1)PSV manifolds for liquid service
(2)Control valve manifolds for high differential pressure or flashing service
(3)Around pump discharge for ANSI 600 or above
(4)Reciprocating pump/compressor piping
(5)Two-phase flow piping
(6)Class 900 and higher piping
(7)400 degree C and higher piping
9.6.2 Braces shall be tied mother pipe and near or at the block valve by welding. When brace material is not equivalent to piping or tying point is 600 mm or more from branch point for high temperature piping, U-bolt

shall be used.
(Fig 9.6.2)
9.6.3 Brace shall be made from flat bar in general and angle bar for long ones as shown above. Double braces shall be installed against vibration such as Item 1 through 5 in section 9.6.1. These braces shall be

positioned as to from triangle as possible.
(Fig 9.6.3)

9.7 Supports for Tubing and Non-ferrous Plastic Piping
9.7.1 Horizontal runs of tubing and the piping shall be supported on steel shape or trays depending on the support spans recommended by manufacturers.
(Fig 9.7.1)
Table 9.7.1 ဓာတ္ပုံရုိက္
9.7.2 Plastic piping including FRP shall be fixed on each support by U-Bolt with rubber sheet or U-Band in order not to concentrate forces on pipe. Plastic pipe vendor standard/recommend supports should be used.
(Fig 9.7.2)

9.7.3 When tubing is arranged on the ground, full length of the horizontal run shall be supported by shapes against damages due to step-on.
(Fig 9.7.3)

10. Spring Supports and vibration dampers
10.1 Spring Supports
10.1.1 Spring supports shall be applicable to anticipated conditions such as start-up, normal operation, turn-down, decoking, regeneration and steam-out, as per the flexibility analysis.
10.1.2 Selection of spring rates for each spring support shall strictly the flexibility analysis. The lower spring rate should be selected for spring supports around pumps and compressors to minimize shifting of loads nozzles depending on operating conditions.
10.1.3 When large axial movements at spring supports are anticipated, the long suspension rods shall be installed on the spring supports in the offset position in order to reduce the inclination.
10.1.4 When lateral movements are grerter than 20mm, hanger type spring supports shall be used except that suitable rollers and/or guides are provided on the bottom support type ones.

ျဖည္းျဖည္းခ်င္း ျဖည့္ဆည္းေပးသြားပါမည္... ;D ပံုေတြလည္း ထည့္ေပးသြားပါမည္.. :P
10.2 Vibration Dampers