DI G ITAL TR AN S FOR MATION
“In situations involving hazardous
gases, it’s critical for facilities to
respond quickly to incidents, from
detecting gas leaks as they happen
to making informed decisions and
mitigating risks wherever possible.”
- Jessica Wood, Honeywell
Siemens’ FS230 clamp-on ultrasonic flow system, launched
in 2020, was developed to improve the accuracy in liquid and
gas flow measurements, even in harsh conditions.

To combat those limitations, the company developed gamma
ray scintillator sensors with lanthanum halide and cerium bro-
mide crystals, materials that have a higher density than sodium
iodide. The higher density levels improve the sensitivity and
spectral resolution of the sensors, enabling faster data acquisi-
tion with more accurate spectroscopic measurements. They also
increase the sensor’s life by reducing high-voltage requirements.

Baker Hughes currently offers the crystal combinations in cus-
tomizable sensor configurations, with different options for crystal
size and aspect ratio, optical interfaces design and construction
and various mechanical interfaces.

The company noted that, while lanthanum halide offers better
light output than cerium bromide and sodium iodide, lanthanum
has a naturally occurring radioactive lanthanum isotope close to
that of potassium . In certain applications, this can contribute to
background radiation. Cerium bromide has less sensitivity than
lanthanum halide, but background radiation is not an issue.

Siemens’ Sitrans FSS200 Widebeam clamp-on sensors are
attached to pipe walls to capture ultrasonic signals gener-
ated from fluid flow. A digital sensor link built into the sensor
sends the data to a transmitter for processing.

24 Gas detection devices
Different types of gases, such as toxic, combustible or volatile
gases, can create hazards for workers on the rig, which means
gas detection is a crucial part of the safety regimen on a rig. Early
detection helps field personnel find and repair leaks quickly,
reducing the risk of major accidents.

The technology for communicating gas hazards has improved
over the years, with real-time monitoring now commonly avail-
able. In addition, the sensor networks that measure environmen-
tal factors are becoming more connected to one another, which
helps onsite leaders identify problems sooner . This connectivity
is a key feature in a line of gas detection sensing technologies
launched by Honeywell in late 2021, the Searchline Excel Plus
and Searchline Excel Edge. These open-path gas detectors have
improved ability to stay online in adverse weather conditions.

Open path gas detectors are designed to identify the presence
of combustible levels of hydrocarbon gases in open areas. They
consist of an infrared source that transmits a focused beam
of infrared light across an area to be monitored into a detector
located some distance away. Gases passing between the trans-
mitter and the detector interfere with the infrared beam, and the
detector uses this drop in energy to determine that gas is present
– the amount of energy decrease is proportional to the level of
gas present.

“Open path gas leak detection creates this invisible line that
senses the presence of flammable and toxic gas passing between
the transmitter and receiver. With these detectors, we’re utilizing
improvements in optical coupling between the transmitter and
receiver to help these devices maintain consistent operational
uptime at long distances and in tough conditions,” Ms Wood said.

Unlike a conventional point gas detector that measures the
amount of gas present in a specific area, an open path detector
measures the quantity of gas in an area that covers the distance
between the transmitter and receiver. This allows a single open
path detector to monitor larger areas than point gas detectors.

Since the open path detector relies on its ability to measure
light intensity, harsh weather conditions can affect the visibility
of the source light. A standard open path detector uses a non-dis-
persive infrared light source, which analyzes the concentration
of target gases based on their characteristic infrared absorption.

These light sources are not filtered, so when the light beam passes
through and interacts with the sample gases in a chamber, only
a portion of the optical energy is absorbed by the gases at their
J U LY/AU G U ST 2023 • D R I L L I N G C O N T R AC T O R