Leak detection is one of the more fascinating aspects of plumbing that uses all sorts of technological innovations to detect and locate leaky pipes. Our plumbers are well versed is discovering water leaks. These methods are diverse and come with their own pros and cons, so we’re offering a two-part guide to the general types of leak detection methods out there.
Internally-based leak detection systems
Methods that use field instruments to analyze the inside of pipes and plumbing systems. These all detect leaks by looking in the pipes themselves.
Hydrostatic test: This is often performed on pressurized pipes before they are made fully functional. It often involves coloured dye being put through the pipe and waiting to see if any coloured water comes out of the pipe where it isn’t supposed to. The pipe is also pressurized to its maximum safe limit to test the strength of the entire system. After these tests have been passed, the pipes are cleared for use. This is a standard test that combines internal and external leak detection methods to some extent.
Pressure/flow monitoring: This is probably the most commonly used method in factory and manufacturing plumbing. The pipes are built with pressure and flow gauges that monitor the internal pipe environment. These gauges are checked regularly and often have built-in alarms that warn people of potential issues.
Balancing methods: Using a series of mathematical formulas based on the conversion of mass. Water entering the pipe is compared with the water leaving the pipe using a series of flowmeters. Any drop in mass is the result of a leak that needs to be fixed. While these tests are accurate, they do not locate the exact location of the leak.
Real-Time Transient Model (RTTM) methods: This is generally considered a step up from balancing methods as it expands on the same basic principles. RTTM uses statistical data using basic physical laws such as conservation of momentum, conservation of energy, and conservation of mass to determine if a leak is present. This method is especially useful because you can determine other factors, like flow, pressure, density, and temperature, in real-time at different points along the pipeline.
Extended Real-Time Transient Model (E-RTTM) methods: Think RTTM but extended over a period of time rather than the immediate present. This method compares current measurements against past statistics to determine leaks, reducing the number of false alarms. E-RTTM is particularly popular for its low false alarm rate and speed since prior data allows for faster computation.
Statistical methods: Using decision theory principles from statistics, a plumbing professional can determine if a pipe is leaking based on relatively limited data. Measurements are made at one end of the pipe and measured against a hypothetical situation that determines if a leak has occurred.
Externally-based leak detection systems
Methods that analyze the external environment of the pipe to see if a plumbing system is leaking. These are methods that monitor a plumbing system from the outside to detect leaks.
Acoustic leak detection: Water and pipes make noise just like everything else and acoustic leak detection helps professionals hear leaks. This method is especially useful for buried pipes that would otherwise require excavation to check a pipe for leaks. By using a microphone, plumbers can hear if and where a pipe is leaking with a surprisingly low false-positive rate. Acoustic water leak detection is incredibly useful and effective at discovering underground leaks.
Infrared radiometric pipeline testing: Using the wonders of infrared detection, plumbing experts can locate and determine leaks by looking at the ground around pipes. Water, or any other fluid, that leaks out of a pipe will be a different temperature than the soil around it. Infrared radiometric pipeline testing analyzes large swaths of land to detect any of these particular anomalies and can send someone to inspect problems. This method is particularly useful with longer pipelines because large amounts of space can be analyzed fairly quickly while still zeroing in on individual leaks.
Vapor-sensing tubes: Special permeable tubes are sometimes installed alongside a pipe to help determine leaks in the future. A pump attached to the tube pushes air through the pipes and past sensors at a constant rate. Anytime anything odd, particularly the contents of the pipe, are sent through the sensors, an alarm is triggered. This method is particularly useful because it finds leaks as they occur, letting professionals quickly contain a leak instead of discovering it after the damage has been done.
Fiberoptic leak detection: Similar to vapor-sensing tubes, fiberoptic cables are installed with the pipes that are sensitive to temperature changes. As with infrared technology, leaks change the temperature of the surrounding environment, causing the cables to change temperature as well. Cables with different temperatures are noted and inspected for potential leaks.
Digital oil leak detection cable: A moulded braid of semipermeable conductors are covered in a permeable insulated braid of cords that are then attached to a series of microprocessors. With these installed, an electrical signal is sent through the conductors and monitored by the microprocessors. Any leaks disturb the electrical signal and are noted by the microprocessors for further inspection. While expensive and fragile, this mode is also extremely sensitive, which is a deal for pipes moving toxic materials, like oil.
Leak detection is one of the more fascinating aspects of plumbing that uses all sorts of technological innovations to detect and locate leaky pipes. These methods are diverse and come with their own pros and cons, so we’re offering our guide to the general types of leak detection methods.