In-Building Gas Line Rehabilitation

NuFlow 945 installation process complies with the methods and quality control requirements of ICC LC1045.

A detailed on-site inspection of the gas pipes is conducted to confirm the condition of the host pipe, the degree of wall thickness loss, and a pressure test for the degree of existing leakage.

Next, NuFlow abrasively cleans the metal pipe by means of an air vortex, to remove any internal tar and/or impurities and to achieve a strong anchor tooth surface profile inside the metal pipe to be barrier coated. The anchor tooth is measured and verified at the exposed pipe ends before applying the barrier coating.

Using NuFlow’s Whirlwind Control Unit, the maximum coating flow distance and required resin volumes are calculated based on the pipe configuration and existing leakage rates; local repairs may be performed to reduce leakage prior to coating (if leakage rates are outside of the manufacturer's recommendations.)

The NuFlow 945 epoxy barrier coating thoroughly covers the inside of the gas pipe using the air vortex of the Whirlwind Control System.

Proper distribution and curing of the barrier coating and the resulting gas pipe leak tightness are verified prior to return to service.

The gas pipe system is tagged to identify that the barrier coating has been applied and labeled with critical O&M guidance.

Aging gas pipes pose an increasing health and safety risk to building occupants, especially in our older urban centers. Prior to NuFlow's NuFlow 945, there has been no code-listed method for property owners and building maintenance managers to extend the service life of building gas pipes. Planned renewal of building gas pipes with NuFlow's NuFlow 945 provides a smart and efficient asset management strategy to safely extend the service life of a building's gas pipe system.

Material

The NuFlow 945 materials have been qualified for use and are listed in accordance with ICC LC1045 for fuel gas pipe rehabilitation, PMG-1528.

NuFlow 945 utilizes a specialty epoxy formulation engineered to flow coat long distances in small diameter pipes while avoiding cissing and pin-holing, and thereby consistently providing an exceptionally low porosity barrier coating within metal gas pipes. NuFlow 945 epoxies are considered to be "zero shrinkage" by the resin industry, enabling a reliably leak-tight fit and mechanical bond to the cleaned and abraded interior surface of the metal gas pipes. The leak tightness reliability of the NuFlow 945 barrier coating for in-building gas pipes has already satisfied code officials in both the UK and the USA.

Validation and Verification Testing

NuFlow 945 has been validated and verified for use according to the following extensive testing criteria:

1.3 Codes and Referenced Standards: 

Note: Any standard referenced herein shall be the current edition of that standard. In instances where the applicable code references a different edition of a given standard, the applicant shall also provide documentation of conformance with the code referenced standard edition. 

1.3.1 International Fuel Gas Code® (IFGC). International Code Council. 

1.3.2 International Residential Code® (IRC). International Code Council. 

1.3.3 ASTM B117, Standard Practice for Operating Salt Spray (Fog) Apparatus, ASTM International. 

1.3.4 ASTM D543, Standard Practices for Evaluating the Resistance of Plastics to Chemical Reagents, ASTM International. 

1.3.5 ASTM D638, Standard Test Method for Tensile Properties of Plastics, ASTM International. 

1.3.6 ASTM D714, Standard Test Method for Evaluation of Blistering of Paints, ASTM International. 

1.3.7 ASTM D1434, Standard Test Method for Determining Gas Permeability Characteristics of Plastic Film and Sheeting, ASTM International. 

1.3.8 ASTM D2240, Standard Test Method for Rubber Property — Durometer Hardness, ASTM International. 

1.3.9 ASTM D2247, Standard Practice for Testing Water Resistance of Coatings in 100% Relative Humidity, ASTM International 

1.3.10 ASTM D3167, Standard Test Method for Floating Roller Peel Resistance of Adhesives, ASTM International 

1.3.11 ASTM D4541, Standard Test Method for Pull-Off Strength of Coatings Using Portable Adhesion Testers, ATM International (see alternative ISO 4624) 

1.3.12 ASTM D5402, Standard Practice for Assessing the Solvent Resistance of Organic Coatings Using Solvent Rubs, ASTM International 

1.3.13 ASTM E2105, Standard Practice for General Techniques of Thermogravimetric Analysis (TGA) Coupled with Infrared Analysis (TGA/IR), ASTM International. 

1.3.14 ASTM G62, Standards Test Methods for Holiday Detection in Pipeline Coatings, ASTM International. 

1.3.15 AWWA C210, Liquid-Epoxy Coating and Lining for Steel Water Pipe and Fittings, American Water Works Association. 

1.3.16 CAN-CSA-Z245.20, Plant-Applied External Coatings for Steel Pipe, CSA Group. 

1.3.17 ISO 8503-1, Preparation of steel substrates before application of paints and related products — Surface roughness characteristics of blast-cleaned steel substrates — Part 1: Specifications and definitions for ISO surface profile comparators for the assessment of abrasive blast-cleaned surfaces, ISO. 

The NuFlow 945 installation process complies with the methods and quality control requirements of ICC LC1045.

NuFlow 945 follows the LC1045 required to hold and inspect points to ensure proper installation at each stage of the process. Submitted as-builts involve exceptionally thorough process documentation for ensuring quality control.

In-building metal gas pipes are first qualified for NuFlow 945 barrier coating through visual inspection for the degree of wall thickness loss and by pressure testing for the degree of existing leakage. 

NuFlow 945 uses NuFlow's Whirlwind System to abrasively clean the metal pipe by means of an air vortex, to achieve a strong anchor tooth surface inside the metal pipe to be barrier coated. The anchor tooth is measured and verified at the exposed pipe ends before barrier coating. 

The maximum coating flow distance and required resin volumes are calculated based upon the pipe configuration and existing leakage rates; local repairs may be performed to reduce leakage prior to coating. The NuFlow 945 epoxy barrier coating thoroughly flow coats the in-building gas pipe system using the air vortex of the NuFlow Whirlwind System. The complete distribution of the barrier coating is visually verified.

Proper curing of the barrier coating is monitored and documented with a dipstick and confirmed and documented with a standard rub test at the exposed pipe ends. A pressure test is then completed to further verify leak tightness prior to the gas pipes being returned to service. The gas pipe system is tagged to identify that the barrier coating has been applied and labeled with critical O&M guidance.