FLO -DYNE

A specialist range for the control ofnoise, pressure pulsations and surgescreated by moving fluids and gases

A DVANCED CONTROL TECHNOLOGY

A WORLDWIDE, WORLD-CLASS SERVICE

Release of high pressure air, steam and gas toatmosphere generates noise that is dangerousto plant personnel and environmentallyunacceptable. Flo-Dyne technology provides themost economical solution with optimised silencerdesign and guaranteed performance. Flexibledesign practice allows easy customisation foreach individual solution combining advancedtechnology, suitable materials and best practicein construction techniques. Standard designsolutions are available for relief valve, steamvent, process gas vent and steam ejector duties.

UNRIVALLED KNOWLEDGE AND EXPERIENCE OF NOISE AND PULSATION CONTROL

Drawing on over thirty years of experience, Flo-Dyne design and supply customisedsolutions for industrial silencing, pulsation dampeners, diffusers and surge equipment

to control noise and pulsation in moving gases and liquids. Used extensively throughoutthe world by gas, water, power, chemical and processing industries, our equipment

provides cost effective solutions that deliver guaranteed results.

Please get in touch for details of any aspect of our range of productsFLO -DYNE

Centrifugal and axial compressors generatebroad band noise with a distinctive peak at theblade passing frequency of the rotor. Thecustom designed Flo-Dyne silencer is built totreat these special noise problems and willreduce the noise radiated by the suction anddischarge pipework, reducing the need forexpensive acoustic lagging systems. Inside thesilencer the acoustic packing is protected byglass fibre cloth and stainless steel mesh toprevent loss of fibre into the gas stream andis arranged for low pressure drop to minimisepower losses.

Built to withstand the high pressure, highnoise level environment downstream ofpressure control valves, Flo-Dyne Control ValveSilencers, when used in conjunction withstandard trim valves, provide the most costeffective means of valve silencing. Using ourpressure vessel construction experience andapplying the acoustic technology from the ventsilencer range, this solution often avoids theneed for costly quiet trim valves.

Flo-Dyne Place, Asheridge Business Centre, Asheridge Road, Chesham, Bucks HP5 2PT Tel: +44 (0) 1494 770088 Fax: +44 (0) 1494 770099 Web: www.flo-dyne.net Email: sales@flo-dyne.net

VENT SILENCERS

CONTROL VA LVE SILENCERS

COMPRESSOR INLINESILENCERS

Model BOSVent SilencerA Vent Silencer for safety relief and atmospheric duties

The Flo-Dyne Vent Silencer is used to reduce unwantednoise from vent or safety relief lines and stacks thatdischarge to atmosphere. Gases handled include steam,oxygen, carbon dioxide, air, nitrogen, as well as natural gasand the many process gases used in industry.

Construction utilises our experience from building pressurevessels to build a robust piece of equipment that canwithstand high temperature steam, high inlet velocities aswell as significant local loads from wind, earthquake andpipework expansion. Full penetration welds are usedthroughout the construction using ASME qualified welders.

The inlet diffuser is built like a pressure vessel and receivesthe full force of the incoming flow. Strength is important toprevent disintegration and erosion under continuous andcyclic operating conditions. Flo-Dyne diffusers are builtfrom standard pipe sizes or rolled from heavy dutyperforated sheet.

The internal acoustic core is built using long strand glassfibre and will withstand temperatures up to 800 deg. F; forhigher temperatures, mineral or ceramic fibres are used.Main shells are constructed from steel boiler plate; forhigh temperature duties stainless steels or high alloysteels are used and for low temperature duties stainlesssteels are used. Internal construction will utilise corrosionresistant Cor-ten, carbon steel or 300 series stainless steelfor the perforated baffles with the acoustic pack designedto accommodate thermal expansion to give stress freeoperation.

Equipment may be self supporting or supplied with pad orcradle type supports. Installation orientation may beeither vertical or horizontal with no change in performance.

Model CISCompressor In-Line SilencerAn Absorptive Silencer designed to handle the special problems createdby air and process gas centrifugal compressors.

COMPUTER DESIGNEDThe CIS Compressor Silencer is an absorptive typesilencer, designed for the short acoustic wave lengthsproduced by centrifugal and axial compressors.Each silencer is custom engineered, using a computerprogram. This program enables the components of theacoustic and flow characteristics of the system to matchthe silencer.

CUSTOM ENGINEERED PACKINGSound is absorbed by viscous drag in the interstices of theglass fibre packing. It is important to match the packingresistance, which creates this drag to the characteristicresistance of the gas handled at its operating condition.To adjust the pack resistance Flo-Dyne changes packingdensity, thickness and fibre diameter.

CUSTOM ENGINEERED SLOT WIDTHA high-speed dynamic compressor produces a certainnoise signature. The silencer must be engineeredspecifically to handle this frequency spectrum. In the Flo-Dyne design, the silencer slot width or distance betweenthe annular packed sections is adjusted for eachapplication.

APPLICATIONThe CIS is used to silence the inlet or outlet of high-speeddynamic compressors handling gas at any pressure. Forlower speed, positive displacement vane and rotarycompressors, see the Flo-Dyne data sheet describing theRCS silencer.

ACOUSTIC SPECIFICATIONSThe CIS silencer provides 20 to 40 dB attenuation. Flo-Dyne will supply specific attenuation performance for eachapplication.

MECHANICAL FEATURESThe CIS internal configuration consists of a series of packedannular cores spaced in accordance with the needs of theapplication. For pressure applications these cores arecontained in a pressure vessel shell which may be built toANSI B31.3 piping code or alternatively ASME or anyEuropean construction.The packing consists of long strand glass fibre which iswound on to annular cores, providing a continuous blanketeffect. Support studs are welded to the facing at regularintervals to act as anchor points for the packing. Layers offibreglass cloth and stainless steel screen are applied andenclosed with heavy perforated metal facing. This tripleprotection assures against loss of packing into the gas

Model CVSControl Valve SilencerA combination reactive/absorptive silencer designed to treatcontrol valve noise in gas and vapour service.

Control valves with high-pressure ratios across them aregenerally very noisy. For stringent silencing requirementsFlo-Dyne has designed the Model CVS Control ValveSilencer which includes a high performance diffuser andan absorptive section. This combination silencer iscapable of providing fluid borne noise reduction up to 50dB.Each CVS silencer is custom engineered for the particularinstallation. The diffuser drilling pattern is selected toprovide a reshaped noise spectrum and optimum backpressure for the valve. The packed section is designed sothat the slot width and length can be varied to provide thecorrect attenuation of the diffuser noise spectrum.

FEATURES• Custom Acoustic PerformanceComputer aided design allows an infinite variation of thesilencer acoustic parameters of slot width and packedlength. The optimum combination of these elements isused for each application to provide the required noisereduction.• Custom Flow Performance

Flo-Dyne engineers design the diffuser and packed sectionto

provide the exact amount of pressure drop required foreach application. For high pressure and high noiseapplication the diffusers can be designed to efficientlyshare pressure drop with the control valve. For lowpressure drop requirements the silencers can be designedto minimise loss.• Drilled DiffuserHeavy duty construction of the diffuser using drilled pipeand full penetration butt welds prevents mechanicalfailure.• Annular Core ConstructionThe packed section consists of a series of annular coreswith the long strand fibreglass spooled into place andanchored by packing support studs. This exclusive Flo-Dyne construction guarantees consistent packing densityand prevents shifting of the packing.• Triple Layer Pack ProtectionThe long strand glass fibre acoustic packing material isprotected by 1) a heavy gauge perforated facing, 2) alayer of fibreglass cloth and 3) a stainless steel screen.This triple protection prevents loss of packing into the gasstream.

GAS DIFFUSER SILENCERType GDS, GDI, GDVA Reactive type silencer designed to control excessive in-line valve noisefor control and regulating valves discharging to pipework or atmosphere.

High-pressure drop across a valve createsexcessive noise and deterioration of valvecomponents. The function of the Gas DiffuserSilencer is to share pressure drop with thevalve, thereby substantially reducing this noiseand wear.

To accomplish this pressure reduction thediffuser passes the flow through many smallholes. Correct hole size and spacing arecritical to diffuser performance. It is alsoimportant to match the diffuser flow capabilitiesto the individual system requirements. Eachdiffuser is custom designed for the particularvalve and piping system it is to be used with.

All standard models are used immediatelydownstream of the system control valve andwill

control valve noise whether the system isdischarging to atmosphere or to downstreampipework.

The Gas Diffusers can be used in conjunctionwith any manufacturer’s valve to achieve aquieter noise environment while reducing therequirements for expensive valve trims.

Our engineers will balance system pressuredrop to minimise valve generated noise. Adiffuser will be selected with the exact flowcoefficient to create the required back pressureat the valve. In the cases where the desirednoise levels cannot be achieved by theinstallation of a diffuser alone,recommendations will be made for pipeinsulation and jacketing or for an absorptivetype silencer.

DESIGNThe Flo-Dyne HUSH PUP is a non-packed, reactive silencer.It works by expanding the incoming flow through many smallholes. The expansion creates a reduction and a frequencyshift of vent noise. By correct selection of hole size, spacingand pattern this reduction can be optimised to produce anoverall quieting effect equal to older style packed silencers.This simple yet effective silencing concept has been testedand proven in thousands of applications as a component partof Flo-Dyne’s line of vent silencers.

APPLICATIONThe HUSH PUP can be used in any high pressure ventapplication where a moderate degree of silencing is required.Typical applications include steam relief valve discharge, aircompressor vents, boiler blowdown lines, gas plant ventsand product dump vents.

ACOUSTIC PERFORMANCEThe HUSH PUP will provide a 15 to 20 dB reduction onmost vent applications. The attenuation curve shown isthe typical performance for a high pressure air vent. Formore critical silencing application the Flo-Dyne VentSilencer is available.

MECHANICAL SPECIFICATIONAll steel construction allows the handling of hightemperature gas or steam. Designed like a pressurevessel, the HUSH PUP can be subjected to high pressure,high impact flow with no problems. Hole sizes, equal orgreater than those of quiet trim valves, prevents cloggingproblems encountered in some sintered metal typesilencers. The all welded design provides years of non-maintenance, trouble free service.

BENEFITS1. Rugged construction2. Effective silencing in non-critical applications3. Simple installation; comes with 150# RF inlet flange4. Long life5 Economical

HUSH PUPVent SilencerA non-packed, reactive silencer for quietingthe noise produced by air, gas and steam vents

Model PDSLiquid Pulsation DampenerAn inline device to eliminate pulsation and reduce maintenance inpower pump discharge lines

GENERAL

The Flo-Dyne Liquid Pulsation Dampener reducesdischarge pressure pulsation by approximately 75%.Actual performance depends on the type of pump,connected piping system and liquid handled.The spherical shape is the strongest arrangement forpressure-containing service … up to 6000 psi, designpressure is standard.Maintenance free, the dampener can be permanentlywelded in the line, saving flange costs and potentialflange leaks. Inline configuration eliminates specialsupport problems

DESIGN

Completely liquid filled, with no moving parts, thisdampener removes the maintenance and gas chargingrequirements.The stationary internals guide the incoming flow into arotating path within the spherical shell. The spinningliquid mass creates a system smoothing/flywheel effect.Viscous drag on the sphere walls and the capacitanceeffect of the relatively large volume located next to thepump further help to dampen pressure pulsation.

CONSTRUCTION

The dampener is all steel construction, with no bladders tofill or replace and virtually no temperature limitation. Withnozzles bevelled for weld, the unit becomes a part of thepiping. Construction may be in carbon steel, 300 seriesstainless steel or a variety of duplex and super duplexsteels.

Model SSCStabiliser/SeparatorAn inline device to eliminate pulsation, cavitation and entrained gas inpower pump suction lines.

GENERALThe Flo-Dyne Stabiliser/Separator, close coupled to thepump suction flange, provides three basic functionsnecessary for smooth, low maintenance operation.Volume Effect - Acting as a mini storage tank, theStabiliser/Separator provides a full charge of liquid when thepump valves open. In systems with marginal available netpositive suction head (NPSH), it prevents cavitation. Alsobecause of its location it acoustically uncouples the pumpfrom the line eliminating acceleration head consideration.Dampening Effect - The gas charge provides acapacitance or spring effect to absorb pulsation created bythe abrupt flow change as the valves open and close.Separation Effect - Entrained gas or vapour is removedbefore it can enter the pump suction manifold where thesudden pressure changes can cause gas to break out ofsolution and create partial cavitation.DESIGNFlow enters and leaves the Stabiliser/Separator tangentially,forming a low-velocity vortex. This vortex and the increasedpath length created by the elevation difference between inletand outlet stimulates the release of any entrained gas. Thefreed gas moves through the perforated centre tube to the

gas or air pocket maintained at the top of the unit.The only maintenance required is the periodicreplenishment of the gas charge. In some applicationswith gas-rich liquids, it is necessary to vent off theseparated gas. Gas/liquid level can be visually observedthrough the sightglass. Since disassembly is not required,normal operating personnel can safely recharge theStabiliser/Separator.

CONSTRUCTIONThe Stabiliser/Separator is of welded steel construction.Standard models are rated 100 psig in accordance withANSI B31.3 code. Inlet and outlet connections areselected to match the pump suction flange. ASME codeconstruction is available.A sight gauge with shutoff valves is furnished for visualobservation of liquid/gas level. Gas fill and drainconnections may be flanged or couplings - as required.Any gas compatible with the fluid can be used as acharging medium. Air or nitrogen are commonly used. Inhighly corrosive service the stabiliser can be supplied withnon-corrodible internals and epoxy coating of wetted steelsurfaces.

Model SAC/SABSurge ArrestorA custom designed hydropneumatic surge arrestor tocontrol water hammer in pipe lines.

GENERAL

The Flo-Dyne Surge Arrestor is located on the discharge orsuction side of centrifugal pumps handling water wherepotential water hammer problems can occur on pumpshutdown, and is also used to control water hammer createdby rapid valve closure.

Pump Shutdown - Flowing water in a pipeline possesseskinetic energy because of its mass velocity. When the watercolumn velocity is abruptly changed (pump shutdown due topower failure, for example) this energy is converted topressure. This pressure occurs in the form of a shock wave(water hammer) which can cause the piping or other systemcomponents to fail.

Valve Closure - In the event of rapid valve closure the samedeceleration of the water column and resultant shock waveoccurs as in pump shutdown. Shock pressures of 3 to 4 timesthe design pressure of the system are not uncommon.

The solution to the above problems is to allow the fluid columnto decelerate gradually. The Flo-Dyne surge arrestor providesa simple, effective method of accomplishing this effect.

DESIGN

Flow enters and leaves the surge arrestor through the energydissipater in the connecting nozzle. The gas charge providescapacitance in the system to absorb the high pressure surgeby compression and re-expansion. Required volume of thesurge arrestor and necessary resistance in the energydissipater are established by computer analysis of theconnected piping system. The only maintenance required isa periodic check of the gas charge pressure. The gas chargepressure is established by Flo-Dyne engineers to satisfy thespecific operating conditions of the application.

CONSTRUCTION

The surge arrestor is of welded carbon steel construction.Standard models are constructed to PD5500 or ASMEPressure Vessel Code, with CE marking as standard.Alternate materials of construction such as stainless steel arealso available to suit the specific application requirements.

A DVANCED PROGRAMMES

Multi-plunger high pressure reciprocatingplunger power pumps produce damaging levelsof pulsation and vibration. Reduction of thesedetrimental forces can be achieved by fitting

the Flo-Dyne liquid filled liquid pulsationdampener. The spherical design offers a low

weight and low cost solution which ismaintenance free with a low cost of ownership.

Units are manufactured to all European andAmerican pressure vessel codes, can be CEmarked and produced in a variety of carbon,

duplex or super duplex stainless steels.

We were the first company to use the sophisticated ‘Method ofCharacteristics’ programme to solve surge and water hammerproblems. Since then we have continued to embrace new developmentsto ensure we remain at the cutting edge of design and manufacture.

Our programme capabilities now encompass all product lines includingsilencer design and performance prediction, structural design, codingcalculations and material selection. FLO -DYNE

Flo-Dyne offers a total service from surgeanalysis, field survey and measurement to

the design supply, installation andcommissioning of hydro-pneumatic surge

vessels for pumped potable, raw water andsewage mains with automated controls and

high quality ancillaries. Accumulators andbladder type surge vessels are offered from

a standard range with a variety of bladdermaterials to enable use with fluids normally

aggressive to the basic butyl rubbers.

Insufficient positive inlet pressure, or NPSHA,at the inlet of a multi-plunger reciprocating

power pump will result in too high anacceleration head leading to damaging

cavitation within the pump.Installing a Flo-Dyne Pump Suction Stabiliser

at the inlet to the pump will eliminate thisexcessive acceleration head. Entrained gases

in the liquid column are encouraged toseparate by the internal design so that the

most complete liquid charge possible isprovided to the pump.

Flo-Dyne, 18 Woodside Road, Amersham, Bucks HP6 6DD, UK Tel: +44 (0) 1494 433737 Fax: +44 (0) 1494 433817 Web: www.flo-dyne.net Email: sales@flo-dyne.net

LIQUID PULSATIONDAMPENERS

PUMP SUCTION STABILISERS

SURGE ARRESTORS

PRODUCT MANUFA CTURING

With rugged construction and a design free ofan absorptive pack, Flo-Dyne multi-chamberreactive silencers are designed to eliminatethe noise and pulsation of the predominantfrequency due to the rotational speed of lobetype and multi-vane compressors.This reactive silencer design achieves highlyeffective reductions in tonal radiation from airmains, for example on sewage treatmentworks, and large reductions in in-pipe pulsationlevels, for example on VSA plants.

FLO -DYNE

High pressure drop across valves causesexcessive noise and deterioration of valvecomponents. Sharing the pressure dropbetween the valve and a Flo-Dyne diffuser willreduce valve wear and noise levels and ofteneliminate the need for expensive valve quiettrims. Built like a pressure vessel, the diffuserwill be designed with the exact flow coefficientto deliver the correct back pressure at thevalve to ensure optimum performance.

Reciprocating gas compressors can generatehigh levels of pulsation in the suction, inter-stage and discharge lines, which can lead toexcessive vibration levels and pipe failure. Flo-Dyne gas pulsation dampeners will eliminatethese harmful pulsations with minimal pressureloss and power consumption.Robust design combined with pressure vesselconstruction provides the most economicalsolution possible.

Flo-Dyne, 18 Woodside Road, Amersham, Bucks HP6 6DD, UK Tel: +44 (0) 1494 433737 Fax: +44 (0) 1494 433817 Web: www.flo-dyne.net Email: sales@flo-dyne.net

REACTIVE SILENCERS

GAS PULSATION DAMPENING

GAS DIFFUSER SILENCERS

Flo-Dyne offer UK and European manufacture to British,European and American pressure vessel codes and standardswith full quality control to ISO9001; CE marking will be appliedwhen required. Uncoded equipment is manufactured in the UKto high standards and all products can be made in a wide rangeof materials from ordinary carbon steels through to duplex andsuper duplex stainless steels.