Pipeline shutoff valves

The shutoff valves from cast iron belong to the class of industrial all-technical fittings, and are widely used for work on objects with not corrosion working environments (steam, water, oil, etc.) at workers pressure and temperature, admissible for case details from cast iron. Most often the fittings are made from gray, high-strength, malleable chugun, is more rare - from heat-resistant, antifrictional chugun. Increase of mechanical properties of gray cast iron (durability, wear resistance) is reached by modifying by the graphitizing materials. The fittings from malleable cast iron are used to temperature of a working environment to 400 degrees, fittings from gray cast iron - to 300 degrees of S. Seriyno produce types of shutoff valves from cast iron: cranes, valves, latches, gates rotary (locks). Cranes distinguish the small sizes and hydraulic resistance. As a lock cranes are subdivided into the spherical and conical crane. Sealing from external environment is provided by tension and omental cranes, connection of cranes to pipelines is carried out with use of couplings and flanges. The most widespread scopes of cranes from cast iron: Gas pipelines at a working temperature 50gradusovs (cranes checkpoints pig-iron, conditional pressure 1kgs/cm2); The Pipelines transporting oil, water, oil at a temperature no more than 100 degrees (cranes stuffing muftovy pig-iron, conditional pressure of 10 kgfs/cm2); Pipelines of big diameters to 3000 mm (the crane spherical pig-iron, conditional pressure 10kgs/cm 2). Locking valves are manufactured up to 200 mm in size, membrane - to 300 mm. Valves have big hydraulic resistance, in communication with what are applied on deadlock sites of pipelines. The most widespread scopes of valves from cast iron: The pipelines transporting water, air, steam at a temperature up to 225 degrees, fuel gas at a temperature up to 50 degrees (valves locking muftovy pig-iron, conditional pressure 16kgs/cm 2); The pipelines transporting phenolic water with impurity of ammonia and sulphurous connections at a temperature up to 100 degrees (valves locking flange of malleable cast iron, conditional pressure 25kgs/cm2); Systems of remote control of the pipelines transporting steam, water, neutral gases at a temperature up to 150 degrees (valves locking of malleable cast iron); On the main and technological pipelines the latch pig-iron - type of pipeline fittings in which the locking element is perpendicular axes of a working environment is widely used. Latches differ in a simple design, small construction length, insignificant hydraulic resistance. With small pressure apply two-disk latches, with big pressure use maple latches. The most widespread scopes of latches from cast iron: The pipelines transporting water, steam at a temperature up to 100 degrees (latches maple with the electric drive flange pig-iron, conditional pressure of 2,5 kgfs/cm2)