Issue Date: September 19, 2005 

Revision Date: June 27, 2011

Ameron International

Dualoy 3000/LCX and MCX Pipe Monitoring System
Liquid Filled Interstitial Space

CONTINUOUS INTERSTITIAL MONITORING METHOD (LIQUID FILLED)

Certification:
Certified as a continuous, liquid-filled interstitial space leak detection system for use only with Ameron Dualoy 3000/LCX and MCX fiberglass double-wall pipe.  Applicable liquids include water and aqueous solutions of brine (i.e., CaCl and NaCl) or glycols (e.g., propylene) in concentration sufficient to reduce evaporation and prevent liquid from freezing in any portion of the monitoring system under extremes of local temperature conditions.
Maximum length is 344 feet.
No restrictions on pipeline diameter.

Operating Principle:
Similar to the methodology that has been applied to liquid-filled interstitial double-walled tanks.
An applicable liquid solution is used to fill the pipeline interstice.
A vacuum may be placed on the interstice to assist as applicable liquid is filled from the low point in the pipeline to minimize trapped air.
The reservoir is the high point of the system and is open or vented at the top and contains a dual-point level sensor.
The dual-point level sensor system monitors the liquid level in the interstitial reservoir and provides an alarm if the liquid level is either too high (ingress of liquid) or too low (egress of liquid).
The method must be used with a dual-point sensor system that will properly fit into the reservoir, is compatible with the interstitial liquid, and is on the NWGLDE list. The spacing between the high and low sensors must be at least 10 inches.
Sensors can be used to shut down the turbine system and/or alert the operator that a potential problem exists.

Alarm Conditions:
For a leak rate of 0.10 gph in to or out of the interstice, the maximum time to alarm for a 10-inch sensor spacing with a reservoir diameter of 3.33 inches is 3.11 hours.
This method declares a pipeline to be leaking when the loss or gain of applicable liquid in the 3.33 inch reservoir is 0.311 gallons.
The change in level in the reservoir is proportional to the volume of fluid flowing into or out of the interstice. It is cumulative and therefore not dependent on the rate of fluid gain or loss.
Time to alarm is based on evaluations conducted using a 30% CaCl2 (brine) solution and a leak (liquid egress) 341 feet from the reservoir.  Equivalent results are expected for other applicable liquids.
Time to alarm for a catastrophic primary pipe failure with a pressure of 38 psi is 8 seconds at a distance of 2.14 feet from the reservoir and 10.48 minutes at a distance of 341 feet. This is based on a liquid level change of 10” or 0.311 gallons in a reservoir that measures 12 inches in height and 3.33 inches in diameter.

Applicability:

Ameron International underground double-walled piping as specified above containing gasoline, gasohol, diesel, heating oil #2, kerosene, aviation fuel, or motor oil.  Other liquids may be stored after consultation with the manufacturer.

Calibration:
Equipment requires no calibration other than an annual inspection.
The electronics must be calibrated and maintained in accordance with the sensor/monitoring equipment instructions.

Comments:
System must be designed and installation done in accordance with the instructions provided by the manufacturer.
Direct burial of pipeline fittings and reservoir is permitted provided the reservoir has an observation manway at grade level.
The liquid level in the reservoir must be at least 12 inches above the water table.
The interstice must be filled from the low point in the pipeline to minimize trapped air.
The evaluation was conducted in an Ameron, double-wall, fiberglass pipeline with an interstitial capacity of 12.97 gallons, an inside diameter of 2.22 inches, and a length of 344 feet.
The alarm conditions are based on a rise or fall of 10 inches of applicable liquid in a reservoir that is 3.33 inches in diameter and 12 inches in length.
Installers must be certified by both the piping and sensor manufacturer.

 | Home | Vendors: A - F | Vendors: G - M | Vendors: N - S | Vendors: T - Z | Method Index | Glossary |

Appearance on this list is not to be construed as an endorsement by any regulatory agency nor is it any guarantee of the performance of the method or equipment.
Equipment should be installed and operated in accordance with all applicable laws and regulations.  For full details, please refer to our expanded "DISCLAIMER" page.