Reliance Articles & Case Studies
Effectively Using Drum Level Instrumentation
Using and maintaining the water-level instrumentation on your boiler is of vital importance for the safety of your plant personnel and the longevity of the equipment in your plant.
The ASME Boiler and Pressure Vessel Code has several sections that define the requirements for the water-level instrumentation applied to boilers that are constructed to this code.
Is Water Flowing Unrestricted from the Boiler to the Level Indicator?
The consequences of a restricted water feed pipe to a primary or secondary low-water device can have devastating results. As many business operations were idled during the pandemic, it may be an especially important time to inspect a boiler’s external piping that feeds the water level indicators and low-water devices.
Restrictions or contamination may develop over time in the water piping that is connecting a gage glass, water column, low-water fuel cutout, or remote level indicator. If a restriction becomes significant, it will result in a false level indication or potentially trapped level in the externally mounted instrument.
Clark-Reliance® Boiler Level Instruments Installed at Uniper’s Enfield Power Station for On-Time Start-Up Despite COVID-19
The Enfield Power Station is a 442MW CCGT Power Station located in Enfield, NE London; it was commissioned in 1999. The current owner, Uniper, who own and operate the facility, contacted Induchem in 2019 with a view to upgrading.
Induchem visited the site and carried out a Boiler Trim Survey, produced a report on compliance to the ASME Boiler Code and prepared a proposal for Uniper. Clark-Reliance also made a joint visit to Uniper Technologies Limited (UTL). During this visit, we used the Clark-Reliance demo equipment to show a group of UTL engineers how the Simpliport and EyeHye SmartLevel equipment operates. Jim Kolbus (via TEAMS) and Amir Hedayatnia of Clark-Reliance joined the meeting, and delivered a training session on compliance with ASME Boiler Code.
What You Should Know About Your Boiler’s Water Level Gage Glass
Water gage glasses continue to be a vital instrument on power boilers that are constructed to comply with the requirements of the American Society of Mechanical Engineers’ (ASME’s) Boiler and Pressure Vessel Code. The code requires that all boilers must be equipped with at least one water gage glass for good reason in addition to the other level-indicating instruments operators rely upon from remote control areas.
The gage glass provides a ready determination of the water level for the operator, especially at critical times, including start-up, shutdown, and during testing of low water fuel cutout devices. A gage glass may also serve as a referee in the event two remote level indicators begin to disagree with each other. Causes for a dispute with the displayed level between multiple remote indication systems may include sludge buildup in sensing lines, restricted valves, or a component failure on one of the instruments.
Smart Technology Is Alive In Conductivity Type Boiler Drum Water Level Systems
Over the past 50 years, conductivity probe type level indication systems have become an industry standard for the continuous display of boiler water levels in control rooms around the world. Operators appreciate the reliable independent level indicator, which some users compare to a “traffic light” for monitoring the water level, among all the other plant controls that are monitored in the control room. As soon as the level indication deviates from normal water level, it gets the attention from the operator.
These conductivity type level indication systems often serve the functions of a remote (indirect) drum level indicator and often as an alarm or trip device. Users trust the conductivity probe technology because it is simply based on whether the conductivity probe (sensor) is in contact with water or not. Most modern systems are capable of detecting very low conductivity water.
Preventing Boiler-Drum-Level-Instrumentation Code Violations
According to The National Board of Boiler and Pressure Vessel Inspectors, boiler controls account for the highest percentage of total documented boilerand pressure-vessel-inspection violations. There are many reasons for this, including neglect, improper maintenance procedures, isolation or elimination of necessary coderequired instruments and accessories, and piping modifications. This article will discuss proactive steps plant-level users can take to reduce the risk of violations related to water-level instrumentation, which threaten the safety of both personnel and equipment.
Keeping Your Boiler & Level Instrumentation Operating Safely
Even though we are in the heating season, it is an important time for good housekeeping and knowing where to find information. This article will offer boiler operators and maintenance personnel helpful information regarding their water level indicators. It is vital to ensure all level indication instruments are in good working order with the illumination accessories attached, as needed.