Liquid Dynamics
Liquid Dynamics Inc. Techincal Services
LIQUID DYNAMICS Ltd. offer Pulsation / Vibraton and Shock - Analysis & Diagnostics + Software Models
Please call toll free USA 1-888-326-7377 WE HAVE PEOPLE - Not voice mail. --44-161-480-9625 UK
Fluid Flow Control Animations
Fluid Flow Control Animations

Shock and pipeline water hammer; technical services pulsation damping with pulsation dampeners Accumulators; hydropneumatic pressure vessels

NEW siteSee, our new American site for your pulsation damper needs!

or the new Liquid-Dynamics at site

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Liquid Dynamics - The Pulsation and Shock Analysis and Prevention Specialists

LDi have been preventing shock, pulsation, pump start-up surge and water hammer for over 35 years. We offer both prevention hardware and software analysis.

Liquid Dynamics Inc. was formed in 1962 and has been dedicated to smoothing flow for the chemical process, hydrocarbon exploration and production, and hydraulic fluid power industries ever since.

We have plants in the USA and UK. Products are manufactured under a quality system, previously: ISO 9001:1994 [DNV Nbr. 95-LON-QA-458 (15105)]. And jointly: ASME "U" Cert 29,289 5 Nov '96 through 5 Nov '99, and through 5 Nov '02 [Kemper/BVQI - QSC 97028/50591 1997/98]. Now via LDi UK - RSA to ISO 9001:2000 valid through 6 October 2007. When you require products assembled under the auspices of that third party they will come via that UK source. We supply hardware (178,123 different products licensed from Martin Packer (Patents, Designs, and Tech Support)) and software for pulse and shock analysis.

In addition, we can provide analysis based on oscillographic data capture, finite element analysis using ANSYS, and pipe vibration frequency analysis using Caesar II.

For more information on shock, pipeline water hammer and pump start-up surge, go to

For more information on pulsation damping and prevention, and acceleration head loss preventors, go to

For more information on accumulators and hydro-pneumatic pressure vessels, go to

Alternatively, find out more about Liquid Dynamics or look at our various trade marks and products.


USA: Call...

Liquid Dynamics Inc.
P.O. Box 506, Hampstead, NC 28443
Tel: 910-270-2738 -- Fax: 910-270-2739
Free Phone: 1-888-326-7377

Europe: Call...

LDI/Membranoflex Ltd.
P.O. Box 47, Stockport Ches. SK5 7BB
Tel: 0161-480-9625 -- Fax: 0161-480-9627

If you have a pipeline or pump user problem which requires pulsation analysis, diagnostics, or prediction by software:
The definitions of many problems can be found at

Who we are
Liquid Dynamics Inc. is a small company based in North Carolina in the USA and Stockport in the UK, employing about 15 people on each site. Products are manufactured under a quality system, previously: ISO 9001:1994 [DNV Nbr. 95-LON-QA-458 (15105)]. And jointly: ASME "U" Cert 29,289 5 Nov '96 through 5 Nov '99, and through 5 Nov '02 [Kemper/BVQI - QSC 97028/50591 1997/98]. Now via LDi UK - RSA to ISO 9001:2000 valid through 6 October 2007. When you require products assembled under the auspices of that third party they will come via that UK source.

Mission Statement
LDi will be the world leaders in pulsation and shock analysis and prevention by focussing on quality, customer satisfaction and innovation at all levels throughout the company. Liquid Dynamics Inc. will be the world leaders in supply of hardware, spares, service, help and advice by following the lead of LDi.

ShockView enables us to quickly and accurately run your proposed piping system, in our computers, and tell you what the maximum level of pump start up surge, or shutdown shock will be. From this first model, which is free to you, we can then determine which of our alleviators is most suited to the needs of your system.
If you wish further models of your system, please contact Liquid Dynamics International in Europe with at least the following information:

Pipe Parameters:
"L" Length, "Di" Internal Diameter, "t" Wall thickness, "bM" Material, (modulus if known)
Liquid specifics:
Flow rate "Q" Kg/Sec. if known, SG, cP viscosity at temp.
Pump manufacturer inertia data:
"S" Seconds Spin-up time (the most important figure.)

PulseDoctor and ShockDoctor DIAGNOSTICS
You have the hardware already? LDi has the tools Certified calibrated signal conditioned transducers. Real time massive paper rate, oscillograph printers. GPIB data stream capture laptops, with FFT analysis. Yes even stethoscopes! Let us identify the heart of the problem, on site.
PulseDoctor and ShockDoctor diagnostics - technical services
You have the dimensions, we will generate pipe response characteristics.
Identify and predict the results of valve action.
Find the pipe shake from pump start-up surge. Enable you to design "Water Hammer" out of your system.
ShockView analysis - check system and prevent problems
Before you invest in system hardware, LDi will run it for you. A "no witchcraft" easy to read set of oscillographic printouts, show you any system dangers, from frequency and amplitude. Allows you to choose the right pump speed and pipe lengths, before your budget is spent.
PulseView software models - LDi technical services

Trade Marks and Products
PulseView Graphical pulsation analysis program
ShockView Graphical water hammer shock analysis
Liquidamics Hypertext screen show software
SysView Piping system model software suite, including the above software
Pulse and Shock Dampers
Flo-Gard Valve, stops flow when shock bursts pipe
Flexorber LP Flow-through shock and pulse interceptor
Pipehugger LP Flow-through shock and pulse preventor
PumpGuard Clear flow tube type suction cavitation preventor
SurgGuard Pump surge dampner (start-up) / absorber / preventor
PipeGuard Gas bladder type pulsation protector
TubeGuard In place flushable damper
WaveGuard Resonance prevention waveguard
Waveguard Acoustic shock preventor
PermaCushion Pre-fill cushion foam
PipeHugger Connects direct to pumps to stop mass acceleration loss
Flexorber Like a Pipehugger LP for higher pressures
LiquiCrat Liquid inside the bag for shocks in corrosive systems
JumboFlex Gas bladder tank for standby shock in non-corrosive systems
Hydropneumatic accumulators
PistoFlex Piston with diaphragm - instant response
PistoLite Sealed closed - no hydrolock, separate bearings
MagDacc Magnetic position volume indicating accumulator for remote readout
Indacc Cascade control for multiple pumps; gives variable flow

Liquid Dynamics International, technical services, diagnostics and analysis and data capture wtih software models. PulseDoctor & ShockDoctor technical services, PulseView and ShockView diagnostics are studied by software computer models or pressure diturbances. Place in your Input, project specifications, all necessary data requirement. Examples of analyses are available.

Click Here or Here to see small publications called Pumps are Pulseless.


Liquid Dynamics provides pipeline and pump user problem analysis, diagnostics, and prediction by software. For water hammer and shock solutions pulsation dampening and shock alleviating devices can be obtained from our associate websites PulseGuard and ShockGuard.


For Hardware see our associate websites: and for further information about pulsation dampeners and pumping systems. and to find large gas bag vessels, jumbo bladders, float separator and big bellows type pipeline shock attenuators and expansion / contraction volume compensators. for more about pulse dampers in pumping systems and water hammer.
Water Hammer    and for more on water hammer, pump start up surge, shut down back flow, & valve closure hammer. and for information about energy saving in pumping systems, standby emergency power, and safety shutdown systems. for a quick view of how each different type of pulse dampener is matched to a pump installation. Pumps make flow, system resistance to flow is pressure, systems make pressure and pressure pulsation. to find protection against excess flow. Guard against toxic spills when pipes burst, guard against gushers and fluid loss when hoses split, Flow-Guard guards against excess flow floods.

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