Needle valves
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Manufacturing Water Valves Industrial Valves Penstocks and Gates Radial Gates Special Applications Needle valves Our firm reserves the right to make any technical changes without any notice to the client.

GENERAL CHARACTERISTICS The network has gained increasing importance trying to conciliate available water reserves and the always increasing request for water. Usually, the network capacity is always greater than the effective request; this implies the necessity to utilize devices able to control the distribution of the water without wasting it. Needle valve is especially designed to realize the function of regulating the water flow, maintaining an easy handling even in circumstances which comport heavy hydrostatic loads at its mouth and a very different exercise pressure. The use of needle...

VALVE SECTION Di Nicola Needle valve can be installed vertically remembering to follow flow direction arrow show on the valve body. It is recomanded to install Di Nicola needle valves following main office dimensioning and advices because flow control valves must be dimensioned based on Flow and water speed data . Most of times max and min. flow rate require an application on two section of Venturi pipes in order to connect the correct dimensioned valve to the main pipeline . In case of installation long a pipeline together with a main shout off valve it is reccomanded to keep a minimum...

TECHNICAL REPORT ON HYDRAULIC BEHAVIOUR NEEDLE VALVE DIMENSIONING Report made on the bases of the “Di Nicola” valve testing, realized by “Istituto di Idraulica Agraria Università di Napoli” (1991 ). The needle valve dimensioning is not based on the conduit diameter but on the pressure conditions in exercise and on the maximum and minimum values of the water flow. Required data Pressure course within the valve (fig. 1 ) 2. Determination of the nominal pressure class (NP) PN = 1, 5 x Hmstat PN = 30 x 1, 5 = 45 m. c. a≈. 4, 5 Bar Section A= Upstream pressure (Hm) Section C= Minimum pressure...

CAVITATION CAUSES AND EFFECTS Cavitation Diagram “SIGMA” Either we regulate or stop a water flow in the concentration area, a reduction of the pressure occurs. When the pressure drops below the vapour saturation in the water, gases are generated with subsequent release of vapourbubbles in the zone of depression. In this environment the bubbles, pushed by the flow, caused by the pressure difference downstream, implode reverting back to liquid form and damagin the inner walls of the piping. The shocks due to the high pressure localized on the walls of the valves and the pipes cause great...

NEEDLE VALVES WITH ACCESSORIES OPERATING UNITS AND ACCESSORIES This type of valve can be supplied as a solution to several flow control problems. The followings are the most frequently encountered a. Down pressure control Needle valve, with down stream positioned pressure gauge controlled by computer, is a very good solution to keep the pressure constant into the down stream pipe line even in presence of big changes of pressure range into the upper stream adductor pipe line. 3 4.Local control electric diagram 2 5.Remote control and signaling panel 6 6.Relief valve PRINCIPLE SKETCH- PLAN N°...

DI NICOLA INFINAM S.r.l. Legal seat: Via Mazzini, 11 66020 San Giovanni Teatino (CH) - ITALY Tel. +39 085 9049480 - Fax +39 085 9049481 Web site: www.dinicolavalves.com email: sales@dinicolavalves.com