DISCHARGE FIXED CONE VALVE (Howell-Bunger Type) This valve is a popular free-discharge valve, suitable both for low head and high head operation. It can work cavitation free under large head drops and high velocities. If containment of the jet is desired, the valve can be supplied with a proper device to confine the jet to a cylindrical shape, rather than a conical shape. It can also been installed to operate in a submerged condition; but for such operation very careful design is required to prevent cavitation. The valve, in a free discharge condition, is capable of dissipating an excess pressure head greater than 120 meters (1000 feet), by a flow velocity up and over 20m/s. It can also be used to regulate the flow. Bubble tight shut-off. Powerplant bypass; flood control or irrigation; to drain reservois; for areating water. Submerged or free discharge (by free jet or confined jet). Size From DN100 to DN1800 (from 2" to 70") (ANSI, ISO, BS, DIN,..) Body in Welded Carbon Steel, Stainless Steel. Any type of painting cycle and/or nickel plating, stellite Electric, hydraulic, electro hydraulic, pneumatic, manual
FLOW CONTROL VALVE Larner Johnson Type Nencini, over more than 30 years by designing, manufacturing and checking control valves, have developped the experience for a correct selection of size, materials, trim styles and actuator. Differently Nencini can also manufacture the valve by following all the required technical specifications. The main data on this type of valve follows: ; Oil (refined, crude); Gas Axial and unrestricted flow path; operated by means of a 90 degree angle trasmission consisting of a pair of worm wheel with worm shaft. Bubble tight shut-off. To achieve all the whatever system conditions many trim style are available; needle, single stage, double stage and individually designed for large capacity and little pressure losses or for very high head pressure losses, always without cavitation problem Size From DN100 to DN3000 (from 4" to 120") Body in: Carbon Steel, Stainless Steel, Cast Iron, Aluminium Bronze Any type of painting cycle and/or nickel plating, stellite Electric, hydraulic, electro hydraulic, pneumatic, manual.
DISCHARGE VALVE Submerged Vertical Sleeve This valve, in the beginning planned from Bureau of Reclamation, utilize the excellent energy-absorbin capabilities of vertical stilling wells and its corner baffles. Nencini, over the years, improved design of the valve and of its shutter (standard or multijet); we can design valve and size the vertical stilling well in front of the hardest system data. The valve is capable of dissipating an excess pressure head greater than 300 meters (1000 feet), discharging a tranquill flow to the downstream canal. It can also be used to regulate the flow. Bubble tight shut-off. Powerplant bypass; Canal headworks; Pipe drop; Turnout. To achieve all the whatever sstem conditions many trim style are available; standard, multijet single or double stage. Size From DN300 to DN2500 (from 12" to 98") Body in Welded Carbon Steel, Stainless Steel. Any type of required painting cycle and/or nickel plating, stellite. Electric, hydraulic, electro hydraulic, pneumatic, manual.
FLOW CONTROL VALVE Vertical Sleeve Type This valve is the in-line version of discharge valve submerged vertical sleeve type; by the particular flow path and the selected trim style, it can be utilized on the pipeline points where there is very high head loss requirement and extremely cavitation risks. Nencini designs the valve and its shutter (standard or multijet) in front of the hardest system data. The valve is capable of dissipating an excess pressure head greater than 300 meters (1000 feet), without an cavitation problem. Bubble tight shut-off. In-line flow/pressure control; powerplant bypass; discharge purpose. To achieve all the whatever system conditions many trim style are available;, standard, multijet single and double stage. Size From DN100 to DN1800 (from 4" to 70") Body in: Welded Carbon Steel, Stainless Steel. Any type of required painting cycle and/or nickel plating, stellite. Electric, hydraulic, electro hydraulic, pneumatic, manual.
ON/OFF VALVE Butterfly Type This valve type started as a simple on/off valve suitable for low work pressure. But butterfly valve features and advantages induced to utilize this valve type in always greater pressure ranges and, when applicable, also for flow control purpose. Nencini manufactures butterfly valve in numerous alternative disc designs; symmetrical, unsymmetrical, double-eccentric, and biplane type. The advantages of butterfly valve, in front of different valve types of the same size, are: light weight and compact size, low cost, quick mounting/dismounting, minimum head losses, easy change of seal, minimum maintenance, bubble tight shut-off in one or both two directions. As on/off valve, for maintenance purpose of pipes, valves, turbines, pump, etc.. As safety valve for big pipes failure, power plants. As check valve in pumps house. Size From DN100 to DN4000 (from 4" to 160") (ANSI, ISO, BS, DIN,..) Welded Carbon Steel, Stainless Steel, Cast Steel, Ductile Iron, Aluminium Bronze. Any type of painting cycle and/or rubber lined Electric, hydraulic, electro hydraulic, pneumatic, counterwheights, manual
FLOAT OPERATED VALVE In-Line Type This automatic operated valve, double flanged type, is used on pipeline. Nencini can perform two different types of automatic control transmitted from the floater to the valve: 1)_ mechanical joint by lever mechanism to the valve shutter; it means gradual closing/opening operations by changing water level and it required a valve site close to the floater. 2)_ hydraulic connection by secondary pipe to the valve element; the valve works as on/off type in front of the maximum water level but you can place the valve far from the floater. Unrestricted or restricted flow path; double or single disc type; anti-cavitation trim if required from system data; bubble tight shutoff. On the inlets to the service reservoirs, tanks or canal, with or without stilling chamber for floater Size From DN50 to DN1600 (from 2" to 60") (ANSI, ISO, BS, DIN,..) Body in: Carbon Steel, Stainless Steel, Cast Iron, Aluminium Bronze Any type of painting cycle and/or nickel plating, stellite Floater (by mechanical or hydraulic connectiones to the valve)
SINGLE AIR VALVES Large Orifice or Small Orifice Type Automatic vent valves solves the following air problems in water mains. 1. Exhaustion of air when the main is being filled and to close when the pipe is full to prevent loss of water. Also to open and admit air to break the onset of vacuum in the pipe during hydraulic transients. 2. To release air which had been dissolved in the liquid under standard operating conditions. Single air valves serve both purpose and are sized with orifices for either (1) and (2), but not both. A proper size selection is important to prevent overpressures, vacuum and pockets of air in pipeline and then not reduce pipeline capacity and efficiency of the line. Nencini designs and manufactures also an anti-slam device, to assemble upstream the air valve and perform a slow closing, where operating conditions cause a regular floater to slam shut. Large air flow capacities; compact assemblies; simple and robust construction; proven efficiency; easy maintenance and minimal servicing. On all pipeline high points and changes in grade; on long ascending/descending stretch at 500 to 700 meters intervals; on all pipeline critical points to prevent vacuums from forming. Size From DN50 to DN600 (from 2" to 24") Body in: Cast Iron, Cast Steel, Aluminum Bronze Trim in: Stainless Steel; Aluminum Bronze; Hastelloy; Rubber Lined Any type of required painting cycle.
COMBINATION AIR VALVES Air Release and Vacuum Breaker Type Automatic vent valves solves the following air problems in water mains. 1. Exhaustion of air when the main is being filled and to close when the pipe is full to prevent loss of water. Also to open and admit air to break the onset of vacuum in the pipe during hydraulic transients. 2. To release air which had been dissolved in the liquid under standard operating conditions. Combination air valves serve both purpose and are sized with orifices for either (1) and (2). A proper size selection is important to prevent overpressures, vacuum and pockets of air in pipeline and then not reduce pipeline capacity and efficiency of the line. Nencini designs and manufactures also an anti-slam device, to assemble upstream the air valve and perform a slow closing, where operating conditions cause a regular floater to slam shut. Large air flow capacities; compact assemblies; simple and robust construction; proven efficiency; easy maintenance and minimal servicing. On all pipeline high points and changes in grade; on long ascending/descending stretch at 500 to 700 meters intervals; on all pipeline critical points to prevent vacuums from forming. Size From DN50 to DN600 (from 2" to 24") Body in: Cast Iron, Cast Steel, Aluminum Bronze Trim in: Stainless Steel; Aluminum Bronze; Hastelloy; Rubber Lined Any type of required painting cycle.