RE: Surge and Water Hammer

Ken,

   If you conduct a risk study using AS 4360 as a basis you could formally reach the conclusion that you have expressed. The risk study could then be sent to the puimp station contractor with a clear message that made them aware of the need for them to ensure that their system should be designed so that no injurious effects occurrred to the network as a result of they not accounting for surge arising from the operation of the equipment.

   You may also like to download "Risk Management Strategies Guide" from the IE Aust website. It is free for members. Others unfortunately have to pay. The risk study should be conducted in UAE with the building owner/ pumping contractor/ designer/operator etc present. You may need a professional risk facilitator to conduct proceedings.

   I dont think that you will find DN1050 Sch40 pipe. In fact it would be unethical not to do the surge study and select the design pressure relevant and take the step of using a thicker wall pipe. You are saving design fees and imposing the cost onto the principal. This could be grounds for reference to the ethics committee of IE Aust. The design codes do not allow you to ignore the surge pressure and just select a thicker pipe. AN extract from a typical code is below.

   Geoff

     301.2.2 Required Pressure Containment or Relief
(a) Provision shall be made to safely contain or
   relieve (see para. 322.6.3) any pressure to which the    piping may be subjected. Piping not protected by a    pressure relieving device, or that can be isolated from    a pressure relieving device, shall be designed for at    least the highest pressure that can be developed.
(b) Sources of pressure to be considered include
   ambient influences, pressure oscillations and surges,    improper operation, decomposition of unstable fluids,    static head, and failure of control devices.
(c) The allowances of para. 302.2.4(f) are permitted,
   provided that the other requirements of para. 302.2.4    are also met.

Geoff Stone
ken eppleston <keneppo@yahoo.com.au> wrote:

   Thanks for the info,

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We specialise in pipe network and waterhammer analysis, pipe stress analysis, the design of buried pipelines and thermoplastic pipe systems.

[Non-text portions of this message have been removed] Received on Mon Jan 16 16:50:00 2006