Datasheet Content
[{"filename":"RAG_en.pdf","text":"RAG\n Air/Gas ratio regulators\n\n\n\n\nelektrogas.com\n\f ELEKTROGAS – Technical Sheet EE181 – 0824\n\n\n\nRAG\nGas/Air ratio regulators for gas\n\nContents\n\n Description ........................................................................ 2\n Features............................................................................ 2\n Functioning and application .............................................. 3\n Technical specifications .................................................... 3\n Gas flow chart ................................................................... 6\n Selection ........................................................................... 7\n Ordering information ......................................................... 8\n Special versions and optionals ......................................... 8\n Design, installation and servicing ...................................... 9\n Standards and approvals .................................................. 9\n\n\nDescription The RAG type regulator has the scope of maintaining a constant air-gas ratio upstream of gas-\n burners on installation without preheated air. It is equipped with a by-pass adjustable on site and\n can be used as zero-pressure regulator.\n\n\n\nFeatures The regulators are made of aluminum alloy die-cast, with a range for inlet/outlet connections from\n 1/2” up to 2”.\n Gas inlet pressure up to 500 mbar, air control pressure up to 120 mbar.\n They are equipped with an adjustable spring and a counterspring, so that gas outlet pressure is\n equal to air control pressure, with a ratio 1:1 and an adjustable offset of +/-3mbar. The offset is\n useful to set gas flow at low fire.\n RAG regulators have been designed for a flow regulation range equal to 10:1 and to generate low\n pressure drop.\n Disc is equipped with a gasket, so RAG is able to regulate precisely very low flow.\n Every model is equipped with a bypass adjustable on-site. Bypass is useful in low fire state when\n a very low flow is necessary or air control pressure is lower 0.5mbar.\n The controls are equipped with inlet pressure compensation diaphragm for a precise regulation.\n A metallic mesh filter protects the regulator seat from dirt contamination (filtration grade <1mm).\n The impulse line is integrated inside the regulator. Special versions with external impulse line are\n available on request.\n Pipe connections meet group 2.\n Suitable for use with non-aggressive gases included in the 1, 2 and 3 families (EN 437).\n Special versions on request (e.g. biogas or hydrogen).\n Provided with pressure test points in the gas inlet, gas outlet and air control chamber to connect\n manometers, pressure switches or other equipment.\n RAG can be used as zero-pressure regulator. In this case it is necessary to connect the vent port\n to a discharge pipe or to install the conversion kit\n In case of installation in Atex area 2 or 22, regulator can be supplied in EX version.\n All components are designed to withstand any mechanical, chemical and thermal condition\n occurring during typical service. Effective impregnation and surface treatments have been used\n to improve mechanical sturdiness, sealing and resistance to corrosion of the components.\n Regulators are 100% tested and fully warranted.\n\n\n\n\n 2-9\n\f ELEKTROGAS – Technical Sheet EE181 – 0824\n\n\nFunctioning and application\n\n A ratio regulator is a device able to maintain a gas outlet pressure equal to the air control\n pressure. Outlet gas and control air pressure act on the two sides of the same diaphragm,\n hence the disc moves until outlet pressure is the same as air pressure. If outlet pressure is\n needed to be a bit lower or higher than air, the spring must be adjusted. If a gas flow is required\n to be present when air control pressure is near zero, the bypass must be set. Variation of inlet\n pressure does not affect outlet pressure because the disc is compensated with a specific\n diaphragm.\n In case of using the control as zero pressure regulator, it is necessary to connect vent port to a\n discharge line or screw the optional kit.\n\n COMPENSATING COUNTER\n ADJUSTABLE DIAPHRAGM SPRING\n BYPASS GASKET\n OF DISC\n\n\n\n GAS GAS\n INLET OUTLET\n\n\n\n\n WORKING\n CONTROL AIR DIAPHRAGM AIR CONTROL\n TEST POINT PRESSURE\n\n\n ADJUSTABLE\n SPRING\n\n\n Fig 1\n This device is usually installed in gas firing systems. Figure 2 shows an example of installation in\n combination with other Elektrogas devices.\n\n VSG\n globe\n RAG\n valve\n Air/Gas ratio\n regulator\n\n\n\n\n Gas\nnetwork VMR-VML\n FG Fast and Slow\n filter opening\n solenoid valve\n\n\n\n\n VF+MZ\n Butterfly valve with\n continuous control\n\n\n\n\n Fig. 2\n\n\n 3-9\n\f ELEKTROGAS – Technical Sheet EE181 – 0824\n\n\nTechnical specifications\n Tab. 1\n\n Main connections Gas threaded f/f ISO 7-1 from Rp1/2 to Rp2\n or ANSI-ASME B1.20 from 1/2”NPT to 2”NPT\n Flanged ISO 7005 PN16 from DN25, DN40 and DN50\n\n Air connection G1/4” for models with Rp main threads or ISO flanges\n 1/4”NPT for models with NPT main threads\n\n Pressure test points Nipples with internal screws and diameter 9 mm\n Plugs with threads G1/8” (models with Rp main threads or ISO\n flanges) or 1/8”NPT (models with NPT main threads)\n\n Ambient temperature -15°C ... +60°C\n\n Gas Inlet pressure Max 500 mbar (50 kPa) or P out + 2.5 mbar for gas\n P1\n Differential pressure between inlet and outlet pressure\n less than 100 mbar is advisable.\n\n Air control pressure 0.5-120 mbar\n P3 Gas inlet pressure has to be always higher than air control pressure\n\n Gas Outlet pressure Air control pressure +/- 3 mbar (adjustable offset)\n P2\n\n Accuracy ±1mbar or ±15% of air control pressure (plus offset)\n\n Max testing pressure Max 750 mbar at inlet chamber – max 200 mbar at air control\n chamber\n\n Flow capacity See charts.\n Bypass flow can be set from 0 to max flow (fig.7)\n\n Filtration grade with metallic filter <1mm\n\n Installation 1/2”-1”: horizontal (with adjustable spring downwards)\n or vertical pipeline.\n 1”½-2”: only horizontal (with adjustable spring downwards)\n\n Gas type Natural gas, town gas, LPG (gaseous) of families 1,2,3 (EN437).\n (for biogas see next page).\n\n Materials in contact Aluminum alloy, Brass, Stainless steel, plated steel\n with gas Polyamide, Anaerobic adhesive, Nitrile rubber (NBR)\n\n Specifications of Free of brass.\n J version Seals made of Fluoroelastomer (FPM).\n for biogas or COG Without bypass.\n\n\n\n\n 4-9\n\f ELEKTROGAS – Technical Sheet EE181 – 0824\n\n\n\n\n Fig. 3\n\n\n\n Tab 2\n\n Overall dimensions [mm]\n Weight\nModel Connection\n (Kg)\n A B C D E F\n\nRAG1 1/2” 100 105 36 159 - - 0,75\n\nRAG2 3/4” 150 141.5 34 182 - - 1,50\n\nRAG3 1” 150 141.5 34 182 - - 1,50\n\nRAG4 1”½ 242 230 58 308 - - 5,40\n\nRAG6 2” 242 230 58 308 - - 5,40\n\nRAG4F1 DN40 242 307 75 324 110 4x18…
