As one of the most popular fittings in fire fighting systems, the grooved pipe fittings are widely used in fire fighting, air-conditioning, water supply, sewage, cement, oil&gas pipeline, mine piping and ordinary piping delivery. Yinuo is spreading all over the world and winning the appreciations from users at home and abroad.  our company focuses on the producing of grooved fittings and couplings. We imported America Inductotherm Group frequency converted introduction furnace, Denmark DISA automatic production line, Germany EIRICH automatic pouring machine, Germany imported spectrometer, etc, the advanced equipment and instruments ensure the producing capacity and quality of products. We have CE/ISO9001/FM and UL certifications covers more than 2000 items and we apply for another 1000 items in 2016 and the amount will reach to 3000 items this year. We have the most professional trade team, all the members here are good at communications in English with professional knowledge of products and will offer you best after-sale service in time whenever you need.   1.Product Name: Rigid coupling for connecting fire protection pipe 2.Material: Ductile iron  3.Dimension : DN25-300(1"-12") or as customer's requirement   4.Surface Treatment : finish : epoxy , painted and galvanized color : red , orange , blue or according to your requirements  5.Advange : Easy to assemble and disassembel, easy to operate   6.Application: Power plant; Heating,ventilation and air conditioning; Industrial plant; Water treatment; Plumbing; Fire protection; Mining and mine processing; Oil field; Marine. This kind of coupling is designed for the pipe bearing moderate pressure. It allows controlled angle, linear and rotational movement at each joint and provides the added advantages of expansion, contraction and deflection. This is usful to accommodate uneven laying surfaces, and movement from thermal changes, setting, seismic effect or other causes. Flexible coupling can be used in fire protection system, feed water, gas system and etc.