Technology

Functionality of the GLD system

Smart detection down to the finest detail

All leakage types inside pressure pipelines produce an acoustic signal that can be detected and distinguished from other sounds inside the pipeline. Passive GLD acoustic sensors therefore produce an acoustic picture of the pipeline.

All leakage types in pressure pipelines produce an acoustic sound which our system can detect and reliably distinguish from other sounds inside the pipeline. Passive GLD acoustic sensors therefore produce an exact acoustic picture of the pipeline.

During the inspection run, all sounds are logged and evaluated by the GLD pig. Through highly sensitive signal and frequency analysis, even the smallest leakages can be clearly differentiated from other noises in the sound profile later in the evaluation. False alarms are therefore prevented. Additionally, familiar background noises aid orientation inside the pipeline.

The GLD 202 Leak Detector is the centrepiece of the GLD pig collection. It stores and processes data. The inspection is carried out during the pump operation, without the pipeline having to be decommissioned. The pig itself is a free-rolling unit which is propelled by the pumped liquid.

The GLD 202 Leak Detector is designed pressure-tight, and is explosion-protected. It is certified for ATEX-Zone 0. There is no other product like it in the world. The detector is installed into a GLD 30x chassis which is tailored to the pipeline dimensions; as a unit they together form the GLD pig. This pig is modularly constructed, meaning you can install the GLD 202 Leak Detector into various sized GLD 30x chassis, in order to pig pipelines with differing diameters.

Following a pig run, data can be easily retrieved via a USB connection, and evaluated using the GLD 710 analysis software.

GLD Leak Detector Pig

Small leakage pinpointed by the GLD software

Simple and precise evaluation of the pig run using the GLD analysis software.

Unparalleled reliability, precise, and cost-effective

The GLD system has many advantages

The GLD system was developed to comply with the provisions of the German TRFL [Technical Regulations for Pipelines (Technische Regel für Rohrfernleitungen), Section 11.4. It is an officially recognised system for detecting subtle leaks within a pipeline.

Standard, fixed monitoring systems are not able to detect the smallest leaks during operation. For this reason, our system is often used in addition to these to cover the requirements of small, subtle leakages.

The GLD system was certified as an alternative to the pressure-temperature measurement procedure. This enables the plant operator to detect subtle leaks without the pipeline having to be decommissioned for a certain period of time. This increases the efficiency of the pipeline, and operational safety. The certified leak detection rate is 6.8 l/h, at a pressure of 6 bar.

Environmental protection should not just be a claim

Environmental protection is standard

Requirements for pipeline businesses to ensure the integrity of their pipeline do not only exist in Germany and Europe. Environmental protection is also increasingly important internationally.

An undetected leak, with a 0.8 mm hole diameter, and 10 bar operation pressure, can result in a loss of 525,600 litres over the course of a year. Hundreds of cubic metres of land can therefore become contaminated. There are many application reports which attest to the enormous importance of a leak detection system for minor leakages by virtue of its much greater sensitivity compared to online systems, and UT [Ultrasound Testing]/MFL [Magnetic Flux Leakage] pigs.

The GLD passive leak detection system is the perfect addition to any continuous system, as well as for other inline inspection systems. The integrity of the pipeline is guaranteed, and existing leakages can be pinpointed precisely.

The reliability and precision of GLD technology is unparalleled. The use of inline leak detection systems means fewer leakages are detected far too late, or by chance, e.g. by residents.

Burst pipeline caused by an undetected leak. Often, this not only means the end for the environment, but also for the pipeline business, it can have consequences on an unprecedented scale.

Surroundings contaminated by thousands of litres of expelled oil from a leaking pipeline.

Bird killed by oil pollution from a leaking pipeline.

The integrated IMU enables ever more precise pinpointing

The end for environmental pollution, and product theft

The latest version of the GLD 20x Leak Detector uses an internal measurement unit (IMU) to record accelerations, e.g. when the device moves over welded joints. Using an specifically developed in-house algorithm, each welded seam of the pipeline can be identified. We have therefore revolutionised location accuracy. Reliable pinpointing of acoustic signals to within a few meters is now possible.

This precision of the detection and location of sounds inside the pipeline even enables our GLD technology to detect and pinpoint illegal hot-tapping spots.

Embedding GLD technology in pipeline integrity systems helps the operator to reduce losses through stolen or expelled media, protect the environment, and increase the reliability of the pipeline.

Technical characteristics of the GLD system

Advantages
  • Leak rate: 6.8 l/h

  • Inspection during operation

  • Location accuracy: a few metres

  • ATEX Zone 0

  • Prevents false alarms

  • Modular construction for differing pipelines

Operating parameters
  • Internal diameter 4″ – 56″, or more

  • Minimum bend radius: 1.5x D

  • Max. operating pressure: 100 bar (higher pressures upon request)

  • Product temperature range: -10 – 60°C

  • Flow velocity: 0.2 m/s – 6 m/s (faster upon request)

  • Operating time: more than 300 h

  • Test length: more than 1,000 km

  • Consistent or variable supply conditions

  • Liquid pipelines

Sensitivity
  • Leak rate: 6.8 l/h

  • Minimum recognisable leak dimension: 0.2 mm

  • Location accuracy: 2-3 m (with the first run)

Safety
  • Certified for ATEX-Zone 0

  • Explosion-protective housing

  • Intrinsic safety

Standards and regulations
  • TRFL – Section 11.4

  • API [American Petroleum Institute] 1175 (Please contact us for further information)

  • DIN EN 1127-1

  • DIN EN 60079-0

  • DIN EN 60079-1

  • DIN EN 60079-7

  • DIN EN 60079-11

  • DIN EN 60079-26

  • DIN EN 80079:36 (DIN EN 13463-1)

  • DIN EN 80079:37 (DIN EN 13463-5)

The GLD system increases the accuracy of leak detection

Further developments for precise pinpointing

To improve pig operation, GOTTSBERG also offers Leak Detection Markers and Pig Signallers.

The flexible, magnetic GLD 611 Pig Signaller is a non-invasive technology, and is mounted to the pipeline in order to detect transitory pigs, and register their exact location inside the pipeline on the SCADA system. In the process, false alarms are consistently prevented through the use of numerous sensors.

Simple installation, and ATEX certification for Zone 1, offers the pipeline operator a wide application range. The GLD 611 central unit is connected outside of the explosion area and forms the bridge between the sensor unit and the system contol (SCADA).

The GLD 501 Ultrasound Marker mounted on the pipeline induces an ultrasound signal (normally 35 kHz) inside the pipeline, and serves as a way point along it. This improves the precision of distance setting by smart ultrasound pigs. Markers certified for Zone 1 can be easily, and non-invasively, attached to any pipeline.

The GLD 50x is also available with other ultrasound signatures upon request.

GLD 501 Ultrasound Marker

GLD 611 Magnetic Pig Signaller