Industry Standard Update 118

IGEM/UP/9 Edition 3 – Application of gas systems to gas turbines and supplementary and auxiliary fired burners

Date issued: 14 June 2023

This Industry Standard Update provides an overview of the recently published revised Industry Standard IGEM/UP/9 Edition 3 Application of gas systems to gas turbines and supplementary and auxiliary fired burners.

Introduction

Recently IGEM published a revision to IGEM/UP/9 Edition 2⁽¹⁾. IGEM/UP/9⁽²⁾ Edition 3 (Communication 1863) supersedes IGEM/UP/9 Edition 2 (Communication 1705), which is now obsolete. The revision to this standard comes into effect immediately.

The following is a brief overview of the amendments in IGEM/UP/9 Edition 3.

General

The standard has been amended to update terms, references to legislation and other standards. It defines the installation requirements for gas systems supplying gas turbines and supplementary and auxiliary fired burners. The standard confirms that the scope no longer applies to turbines fuelled by fuel oil.

Sectional changes

Section 7 contains changes to acceptable standards for pipework materials. Purging instructions have been removed and it now advises that the system must be purged in accordance with IGEM/UP/1.

S7.4.2.2 previously stated a test pressure and now specifies that the final test pressure shall not exceed 90 per cent of the specified minimum yield stress (SMYS).

S7.6 Inspection and maintenance planning has more detailed information for inspection and maintenance and advises IGEM/UP/2 to be referenced to assess the inspection and maintenance requirements for the installation. A risk assessment must be completed in accordance with DSEAR. Any leak testing deemed to be required from the assessment must be performed.

AECVs and other appropriate valves should be checked for correct operation. An additional reference to test instrumentation relating to combustible gas analysers and hydrogen-rich gases is now included.

S7.6.8.1 states that a monitoring programme should be created and is to be conducted at intervals, generated from a suitable risk assessment. This survey must confirm accessibility, etc. A gas leakage inspection is also to be conducted at intervals determined by a suitable risk assessment.

Section 9 directs vent pipe design, installation and testing to be completed in accordance with IGEM/UP/2 Edition 3 and should be tested to the appropriate standard used for the testing of the installation pipework.

The location of detectors from flammable gas detection systems is listed in S11.1.2.6 and states that they should be positioned in the vent outlet of the enclosure and that a two-stage alarm/shutdown system is preferred. The device should cause an automatic lock-out situation and operation of the AIV and dump valves.

S11.1.3.1 is a new addition and specifies the requirement for general cooling air in addition to combustion air. The actual requirement should be specified by turbine manufacturer or equipment packager.

Ventilation around any potential leakage points and gas turbines is covered in S12.3.3 and shall be determined through a DSEAR assessment. Electrical systems must comply with 2016 (SI 1996/192 ATEX) rating.

A note in S13.2 states that downstream duct work and combustion must be diluted to a safe level and ensure that ancillary equipment temperatures and the temperature within the duct do not exceed 450°C.

Section 17 covers operating and maintenance instructions. This section now contains more technical detail and includes reference to gas valve tightness testing and operation, safety shut-off valve operation, proving system and flame detection systems, turbine safety circuits, and alarm trip systems. Written procedures must be prepared for all maintenance items and records must be kept. The work must be completed by a person competent to work on a compressor or booster.

Appendix changes

Some changes have been made to the appendix guidance: these include the addition of new units and definitions, and a vent pipe design diagram detailing size and termination position. New guidance has been added on checking safety shut-off systems.

Bibliography
(1) IGEM/UP/9 – Edition 2 – Application of Natural Gas and fuel oil systems to gas turbines and supplementary and auxiliary fired burners (Communication 1705).
(2) IGEM/UP/9 – Edition 3 – Application of gas systems to gas turbines and supplementary and auxiliary fired burners (Communication 1863).

Summary
As previously stated, this Industry Standard Update is only a brief overview of the information contained in the amended standard. Registered businesses should be aware that they have a responsibility to ensure that they are fully apprised of all the requirements of the whole published standard and their practical application.