CSA - CGA 6.18
Internal Relieved Service Regulators for Natural Gas
|Publication Date:||1 November 1995|
The regulators shall be designed specifically to deliver natural gas from high pressure (2 psig [13.8 kPa] to 125 psig [861.8 kPa]) gas distribution systems, reducing the pressure at all times and under all conditions to a standard nominal delivery pressure adjustable between 5 - 9 inches of water column (1.24 - 2.24 kPa).
The regulator shall be capable of operation over (i) a temperature range of -2O'F to 150'F (-28.9'C to 65.6.C) unless a lower temperature of -4O'F (-40%) is specified by the manufacturer and (i¡) an inlet pressure range of 2 psig (13.8 kPa) up to the pressure recommended by the manufacturer but not exceeding 125 psig (861.8 kPa).
All materials in the regulator and component parts shall be suitable for the intended use and shall be chemically resistant to natural and man-made dilutents normally found in natural gas.
Any material consisting of 100 percent copper shall not be permitted. Brass parts shall contain no more than 75 percent copper.
If corrosion of a part will interfere with the function of the regulator or otherwise cause deterioration, the part shall be of a corrosion-resistant material or be provided with a corrosion-resistant protective coating.
Regulators shall bear a permanent and legible marking as per Section 1.12, MARKINGS.
Regulators shall be constructed of quality materials in a workmanlike manner in order to attain gas tightness, stability of performance, and sustained accurate regulation over a period of time and over a range of operating conditions with a minimum of maintenance, when regulating all types of gases normally used in distribution systems.
Regulators shall have an internal static pressure sense point with no external static or control lines.
This Standard contains SI (Metric) equivalents to the yard/pound quantities, the purpose being to allow the Standard to be used in SI (Metric) units. If a value for a measurement as given in this Standard is followed by an equivalent value in other units, the first stated is to be regarded as the requirement. The given equivalent may be approximate. If a value for a measurement and an equivalent value in other units are both specified as a quoted marking requirement, the first stated unit, or both shall be provided.