1 / 12

WELCOME TO

This presentation discusses the challenges and solutions for improving the reliability of dry gas seals in MRO operations. The focus is on the primary seal/buffer gas supply and separation seal leakage issues. The case study involves a specific stage of a steam turbine-driven compressor and the modifications made to ensure continuous buffer gas flow and prevent oil ingress.

redfern
Download Presentation

WELCOME TO

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. 2014 - MRO Dry Gas Seal Reliability Improvement WELCOME TO

  2. Presenter • Presenter: Ali Shallwani • Career Summary: • Rotating Equipment Specialist at Nova Chemicals (2014-onwards) • Rotating Equipment Engineer at Saudi based petrochemical company (2011-2014) • Machinery Engineer at Pakistan based fertilizer plant (2007-2001) • Career Highlights: • Vibration Diagnostics, Initiatives related equipment design and performance improvement, RCFAs, FMEAs, PHAs

  3. Problem Statement • Primary Seal /Buffer Gas Supply • Primary Seal Gas + Separation Seal Leakage • Separation Seal Supply • Low buffer flow for dry gas seal

  4. Application • Service: CO • Machine: 7 Stages Integrally Geared Compressor (Steam Turbine Driven) • Specific Stage: 7th Stage • Operating Profile: 65barg Discharge Pressure

  5. Internals Rotating face with spiral profile (uni-direction seal – specific case) Stationary face (spring supported) Espey rings or barrier seal Sleeve

  6. Significance • In case of low buffer flow – there is potential of oil ingress into the seal housing. • Potential failure of seal assembly • Equipment shutdown

  7. Description

  8. Description • N2 is used as buffer gas – which then escapes through the primary vent (to the flare). • N2 pressure should be essentially maintained at recommended value to achieve this desired flow rate. • As standard design, there is no trip security associated with buffer flow.

  9. Troubleshooting • The seal gas system for this specific set-up was checked. The important fittings and installations on the system includes transmitters, control valves and orifices. • The low buffer flow was observed on 7th stage of the equipment – the remaining 6 stages were healthy. • Potential leakage within the system was checked. • Restriction within the system was to be checked.

  10. Inspection • The seal was disassembled for inspection. • All internals were found in stable condition. • The espey rings through which the buffer gas flows were found slightly rubbed against sleeve surface.

  11. Modification • The type of espey ring was modified such that grooves were introduced to ensure continuous supply for N2 in case of tight clearance / contact.

  12. Outcome • The desired flow rate through espey ring was achieved – and reliability of the overall system was ensured.

More Related