Elektrogas NC automatic reset slow opening fast closing

[{"filename":"VMH_en.pdf","text":"VMH\n\n Safety shut off valves for gas\n with hydraulic actuator\n\n DN65 … DN300\n\n\n\n EE175 -0124\n\ndelta-elektrogas.com\n\f ELEKTROGAS – Technical Sheet EE175 - 0124\n\n\n\n\nVMH\n\nContents\n Description ………………………………………….. 2\n Features …………………………………………….. 2\n Functioning and application ………………………. 3\n Technical specifications …………………………… 4\n Gas flow chart (pressure drop) …………………… 6\n Ordering information ………………………………. 8\n Special versions and options …………...………… 8\n Design, installation and servicing …......……….... 9\n Standards and approvals …………………………. 10\n\n\n\n\nDescription The VMH type valve is a safety shut off valve for gas with hydraulic actuator. It is suitable for air\n or gas blocking and releasing controls, required in the main pipe of gas power burners,\n atmospheric gas boilers, industrial kilns and others gas consuming appliances.\n See Tab. 2 for maximum operative pressure for every model.\n\n\n\n\nFeatures The valves are made of aluminum alloy with a range for connections from DN 65 up to DN 300.\n Pipe connections meet group 2.\n Suitable for use with air and non-aggressive gases included in the 1st, 2nd and 3rd families (EN\n 437).\n Special versions for aggressive gases.\n The valve is open only when energized: if, for any reason, power supply goes down, the valve\n closes immediately (intrinsic safe).\n Qualified for continuous service (100% ED).\n Size DN65-80 is equipped with flow rate adjustment.\n An incorporated fine mesh filter protects the valve seat and disc as well as downstream\n components and prevents dirty contamination.\n Provided with G1/4 pressure gauge on two sides in both inlet and outlet chamber to connect\n manometers, pressure switches, leakage tester or other gas equipment.\n The actuator is provided with ISO 4400 plug for easy cabling. The protection class is IP65 (EN\n 60529).\n The actuator is provided with a led to visualize when it is energized.\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 Valves are 100% tested and fully warranted.\n\n\n\n\n WARNING\n This control must be installed in compliance with the rules in force.\n\n\n\n 2-10\n\f ELEKTROGAS – Technical Sheet EE175 - 0124\n\n\n Functioning and\n application The VMH type valve is a safety shutting\n device using auxiliary power supply.\n\n When it is de-energized, the spring pushes\n on the seal disc, keeping the gas passage\n closed. In this condition the inlet chamber is\n filled with pressurized gas that forces on the\n disc, improving the seal.\n\n When the actuator is powered, the relief\n valve closes, the pumps starts and the\n pressurized oil pushes the piston. The disc\n opens slowly against the combined force of\n spring and gas pressure.\n\n When the disc reaches the end stop, the\n pump is turned off and only the relief valve is\n consuming power.\n\n\n\n If the power supply is shut off, the relief valve\n opens and the disc closes rapidly,\n interrupting the gas flow.\n\n Fig. 1 shows a sketch of a VMH valve.\n Fig. 1\n\n This kind of valve is normally installed as safety and regulating device in gas trains, for industrial\n applications and gas firing systems. Fig. 2 shows an example of installation, in combination with\n other Elektrogas devices.\n\n Hydraulic\n valve VMH Hydraulic Pressure Pressure\n with PCS valve VMH Regulator Gauge Solenoid valve\n R MG witl VMR-VML\n Ball button\n Valve Valve valve ME Pressure\n VSG Gas Filter leak switch\n FG tester PSG\n LD\n\n\n\n\n Consumer\n Gas\nnetwork Fig. 2\n\n\n WARNING\n Location and mode of installation must be in compliance with local rules in force.\n\n\n\n\n 3-10\n\f ELEKTROGAS – Technical Sheet EE175 - 0124\n\n\nTechnical specifications\n Tab. 1\n\n Connections Flanged PN16 – ISO 7005 from DN65 to DN300\n\n\n Voltage rating (-15%/+10%) 230 VAC or 110 VAC 50/60 Hz\n\n 20VA (START 110 W)\n Power consumption\n Only for DN 250–300: 25VA (START 115W)\n\n Ambient temperature -15°C / +60°C\n\n\n Max. operating pressure see Tab. 2\n\n\n Flow capacity see Tab. 2\n\n\n Opening time see Tab. 2\n\n\n Filter 600 µm, metal mesh\n\n\n Protection class IP65 (EN 60529)\n\n\n Cable gland Plug ISO 4400 with cable gland PG9\n\n Materials in contact with gas Aluminum alloy\n\n Brass\n\n Stainless steel\n\n Plated steel\n\n Anaerobic adhesive\n\n Nitrile rubber (NBR)\n\n Fluoroelastomer (FPM)\n\n Polytetrafluoroethylene (PTFE)\n\n\n\n\n 4-10\n\f ELEKTROGAS – Technical Sheet EE175 - 0124\n\n\n\n\n Fig. 3\n\n Tab. 2\n\n Flow Overall dimensions [mm]\n Opening\n Pmax Max cycles Weight\n Model Conn. time *3 Kvs 4\n [bar] per hour * A B C D Int h [Kg]\n [sec]\n [m³/h]\n\nVMH7 *1 *2 DN 65 1,6 10..15 83,0 60 200 305 350 536 145 4x18 14\n\nVMH8 *1 *2 DN 80 1,6 10..15 92,0 60 200 305 350 536 160 8x18 14\n\nVMH9 *1 *2 DN 100 1,3 15..25 152,0 40 250 350 366 571 180 8x18 18\n\nVMH93 *1 DN 125 0,5 25..40 250,0 30 310 460 461 671 210 8x18 34\n\n VMH93U *2 DN 125 1,3 25..40 250,0 20 310 460 461 671 210 8x18 34\n\nVMH95 *1 DN 150 0,5 25..40 315,0 30 310 460 461 671 240 8x23 36\n\n VMH95U *2 DN 150 1,3 25..40 315,0 20 310 460 461 671 240 8x23 36\n\nVMH98 *1 DN 200 0,2 35..50 476,0 20 370 546 494 730 295 12x23 52\n\n VMH98U *2 DN 200 1,3 35..50 476,0 15 370 546 494 730 295 12x23 52\n\nVMH910U *2 DN 250 1,3 40..60 660,0 15 405 600 560 852 355 12x28 59\n\nVMH912U *2 DN 300 0,6 45..75 970,0 15 460 700 596 923 410 12x28 106\n\n *1 models with certificate GAR - 0063CO1798\n\n *2 models with certificate PED - 0497/2638-2664/13\n\n *3 opening time depends on ambient temperature, real voltage, frequency and inlet pressure\n\n *4 VMH valves are not suitable for very high number of cycles, as used in pulse firing.\n\n\n\n\n 5-10\n\f ELEKTROGAS – Technical Sheet EE175 - 0124\n\n\nGas flow chart\n(Pressure drop)\n\n\n\n ( ) ( ) ( )\n\n\n\n\n n m h\n\n\n\n\n . . . . .\n .\n .\n .\n\n\n d m ar\n\n Fig. 4\n\n\n\nFormula of conversion Tab. 3\n Gas type Density\nfrom air to other gases ρ\n…