The Pipeline Shock Prevention People
Pump Start-up surge, Valve closure shock, Pump shutdown back flow bang.
Large vessels for high pressures with matching bladders, diaphragms, gas bags, and bellows, for over a third of a century.

ShockGuard Ltd. offer shock alleviators. | Please phone 44(0) 161-480-9625
We have people not voicemail. | Free Phone UK 08080-567-7423
Fluid Flow Control Animations
Fluid Flow Control Animations


The Problem: Surge Suppressors are the solution The height of the peak pressure is from the rate of mass deceleration. The frequency is from the pipe length. The negative pressure "valley", between the peaks may be the most dangerous. When the negative drops off plot all together, the liquid is flashing. Seals and gaskets may be "sucked in".

NOTE, NB The faster the valve closes, the higher the pressure spike.
It is very important to put an accurate figure on valve closure time*

SURGEGUARD surge suppressors will prevent water hammer from fast valve closure.

Surge Suppressors

Reservoir 2. Centrifugal Pump 10. SurgeGuard 11. Emergency fast shut down valve

The system could have a water hammer problem if the valve was closed to quickly or the pump was started up too quickly. The SurgeGuard surge suppressor (provided it has been correctly sized and installed) will prevent any water-hammer occurring. When the valve is closed too quickly, normally all the liquid would have to suddenly stop. SurgeGuard surge suppressors provide a space into which the liquid can flow. As it flow into the space, it compresses a gas-filled bladder, so as the space fills, the bladder provides an increasing resistance. In this way, the liquid can be decelerated more slowly, preventing the formation of a shock wave. The same process happens when the pump is started up too quickly.

Alternatively, LDi's ShockView software can provide an analysis of the system to determine how slowly the valve should be closed or the pump started up to prevent the shock wave forming.

For corrosive systems, where an elastomer is compatible, vessel may be carbon steel

The SurgeGuard consists of a liquid-filled bladder in a container. The process liquid only comes into contact with the bladder and the connection plate, so compatibility is only an issue with those parts. This means that even when the process liquid is corrosive, the bulk of the unit can be make from conventional materials and more expensive resistant materials only need to be used for the bladder and connection plate. In addition, the bladder is a one-piece molding, unlike many other bladders which are made in pieces then glued together, so compatibility issues between the process liquid and the glue are also avoided.

Surge Suppressor

Air / N2

The SURGEGUARD may be mounted horizontally
Surge Suppressor
This SURGEGUARD has titanium wetted parts for chemical duty.
For installation below ground level, in shallow pits to avoid flooding, the
SURGEGUARD has its bladder anchored at the open mouth and the dome end, to enable horizontal working. This feature proves valuable on military air fields for refueling line protection from fast valve closure water hammer, at the aircraft dispersion bunkers.
The "liquid in The Bladder" feature, with cushion pre-fill N2 in the epoxy coated vessel shell allows low coast vessels to be used in severe liquid compatibility duty. Only the liquid contact parts of the base require exotic materials.

LDi - analytical and modeling services and software Visit LIQUID DYNAMICS Intl. Ltd. LDi offers analytical and modeling services. They predict these and similar problems, before pipe systems are built. ShockGuard is a licensed run time user of the LDi Ltd. software, ShockView. ShockView enables us to quickly and accurately run your proposed piping system, in our computers and you what the maximum level of pump start up surge, or shutdown shock will be. Centrifugal pump shock and surge frequency waves


Shock Alleviators
Water Hammer and Pipeline Surge / Shock Alleviators
STOP Pump start up surge, Valve closure shock, and Shut down back flow water hammer.
call toll free 1-888-326-7377, UK Europe -- 44(0)161-480-9625
or Contact ShockGuard Shock Alleviators.

Understanding Pipeline Surge / Shock Alleviators
Shock alleviators and shock accumulators do not alleviate shock, nor do surge alleviators and surge accumulators alleviate surge. SurgeGuard, JumboFlex, and Floatolator all work in the same way. They provide a soft place, so that the pump does not have to instantly accelerate all the liquid in the pipe system when it starts. Similarly, they provide a place into which flow can continue, for a time, against increasing resistance, when a a valve has been slammed. In both cases, because time has been increased, peak pressure generation is decreased. In short, they all prevent the peak pressure from being generated. / Shock Alleviators

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