Surge analysis in piping

PLS) that calculates time-invariant pressure, temperature and flow profile throughout a pipeline network for specified boundary conditions and network element set points. You may do the same analysis by using BOSFluids and CAESAR II. Also if the monitor is opens, the water will rush towards the nozzle because the monitor valve will have a much higher capacity for air than water. Once the water reaches the nozzle it will slow down very fast due to the much lower capacity for fluid in the valve - this may also cause a water hammer.

These sudden velocity changes can be caused by the operation of valves and pumps , or by expulsion of air from the piping system.

With proper planning and design, the effects of surge pressures in a system can be minimized. A surge analysis for long pipelines often in a recommendation to use surge relief valves as the primary surge control device. In this application, the surge relief valve would be required to open quickly to relieve a sudden rise in pressure upstream of a booster pump.

Hydraulic transient”, “surge pressure” or, in water applications, “water hammer” is a type of hydraulic transient that refers to rapid changes of pressure in a pipe system that can have devastating consequences, such as collapsing pipes and ruptured valves. Proposed solutions take into account short term and long term plans by owners and planned operation. This may cause a very high surge.

The effect of surge on any line, as identified by the Process group or a specialist agency, shall be considered in piping analysis.

However two concurrent occasional loadings need not to be considered in piping stress analysis. Usually for a main LNG lines a surge analysis will be studied during shut down operation in a specialised software(eg, Pipenet). Since the valves are not stoped a sudden the surge pressure will not be that high.

We have many years’ experience of doing pipeline surge analysis for clients in the water, wastewater, fuel systems, oil and gas and renewable sectors. From preliminary review and concept design to finial design and safety case studies. Generally, water hammer or surge in liquid line occurs, when there is a sudden closure of a valve (mostly ESD valve) on the downstream end of a pipe. The parameters of critical importance are the length of the pipe, size, MOC (whether Metallic or Plastic), fluid flow and fluid type. When flow is suddenly stoppe flow inertia causes a pressure surge at the valve, with a shockwave propagating through the pipeline.

Engineers need to know the maximum pressure surge to correctly design the pipe, valve andother fittings. Water hammer is a common phenomenon. Surge Analysis PULSCO’s Surge Analysts are experienced in modeling of a large variety of fluids and pipelines, including all pumps and valves, whether this is for transmission or distribution. INERTANCE has performed the surge analysis (water hammer) for long pipeline as well as network pipe system with various process upset conditions. The equivalent static analysis in Caesar-II is performed to simulate slug loading in piping system using the above formula for calculating slug force.

Forces Induced by Surge Pressure. Surge analysis using BOSfluids and evaluation of the unbalanced forces on the piping system.

Dump Lines Critical lines transporting dangerous chemicals at high pressures. The magnitude of the pressure surge is determined by the velocity of the fluid in the pipe and the rate at which this velocity is changed. The effect of a sudden velocity change depends on the length of the pipe and of the closing speed of the end valve. Joukowsky pressure rise.

Process Engineering Guide: GBHE-PEG-FLO-3Introduction to Pressure Surge in Liquid Systems Information contained in this publication or as otherwise supplied to Users is believed to be accurate and correct at time of going to press, and is given in good faith, but it is for the User to satisfy itself of the suitability.