PUMP (API674) AND COMPRESSOR (API618) STUDIESLet us help you prevent vibrations in the field

The varying flow caused by reciprocating pumps and compressors leads to a pulsating flow within the connected piping. Excessive pul-sation amplitudes can lead to mechanical vibrations and thereby fa-tigue failure of the piping or supporting. To avoid these problems good system design is key and here DRG can be your perfect partner.

Our pulsation assessments for compressor systems are performed in conformance with the industry standard API 618 and those for pump systems in conformance with API 674. For both types of study DRG combines acoustical and mechanical simulations to check the susceptibility of your system to excessive vibrations. DRG engineers are well versed in finding practical and cost-effective solutions what-ever the stage of plant under design.

VIBRATION ROOT CAUSE ANALYSIS Why does your vibration occur? What is the most economical fix?

Do you see noticeable vibrations in your piping system? Are you worried that this could lead to fatigue failure? If the answer to both of these is yes then you should think about carrying out a ‘root case analysis.’ The DRG approach to such a situation has three steps: (1) understand the cause, (2) determine if fatigue is a risk and (3) suit-able remedial action.

The first stage in solving the problem is to understand the mecha-nism by which they are occurring. Typically a site-visit, often with vibration measurements, coupled with computation simulations forms the starting point. Once the mechanism is understood, DRG will determine how much of the design fatigue life has been used and whether action needs to be taken to ensure a safe system. When remedial action is necessary, we pride ourselves on working closely with the operator to ensure that practical and economic recommen-dations are made.

Pulsation | Vibration | Solutions

PRODUCT SHEET

The engineers in our team at DRG regularly work on projects across a multitude of technical disciplines. We have a flexible working structure, which means that we can help you immediately. At DRG we are creative thinkers and we work closely together with you, to de-velop practical and economical solutions.

Dynaflow Research Group (DRG) specializes in the advanced end of the engineering spectrum around the subjects of flow, vibrations/pulsations, mechanical and fiberglass engineering. Across these subjects DRG provides engineering consulting services, software and training courses.

PULSATION SUPPRESSIONOptimize pulsation reduction against operating costs

Installing a reciprocating compressor or pump without any pulsa-tion suppression will for most engineering systems lead to exces-sive, vibration inducing, pulsation amplitudes. Thus conformance with the API 618 and API 674 design codes is only possible with adequate pulsation suppression devices. DRG understands the compromises that need to be made when designing the suppres-sion device.

In configuring a compressor bottle, the designer has to balance the requirement for pulsation dampening, with size constraints and introducing operating cost inducing pressure losses, and the possibility that resonance modes inside the bottle are excit-ed. Whilst when sizing the accumulator for a reciprocating pump system the gas volume is not the only relevant parameter. Here the designer also needs to consider the accumulator location, fre-quency response and the piping geometry.

ABOUT DYNAFLOW RESEARCH GROUP

Houtsingel 95, 2719 EB, Zoetermeer, the Netherlandswww.dynaflow.com, info@dynaflow.com

BOSPULSE

BOSpulse is our commercially available pulsation analysis soft-ware built based on our project experience. It has a time domain method of characteristics (and frequency domain harmonic) solver and has a user-friendly interface designed for the piping engineer.

For dynamic piping calculations we also make use of the wide-ly used stress package CAESAR II from Intergragh. Here we are official training partners and actively help with developing their dynamic solver. When shell resonance modes become important then ANSYS or FEMAP will be used.

For a root cause analysis DRG can perform on-site vibration mea-surements using our 4 channel sensor setup. If a site visit is in-feasible then DRG can also use those measurements taken by the client or a third party.