Needle Valve Range

Fields of application

The main characteristic of needle valve is the capacity to modulate water flow rate and elevated differential pressure. The needle valve NGL is able to do a linear manoeuvre also in a presence of relevant partialization degree although high inlet pressure and big exercise difference of pressure. The possibility to be actuated by electrical devices permit to use this valve in combination with control system to realize multiple function.

The needle valve controls the water flow rate through the axial movement of a shutter operated by a connecting-rod and crank mechanism. The inlet flow rate is channeled into a round section passage which gradually decreasing and then increasing from the intake to the sealing seat.

The internal profile of the valve is designed to optimize the hydrodynamic profile in order to have:

• low head losses whit valve completely open
• minimize cavitation phenomena in case of big differences between inlet and outlet pressures of valve. In this case the valve can be equipped with a special stainless steel cylinder for hydraulic loads dissipation

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Range

The needle valve E508 NGL is proposed in standard versions:

• Manual or motorized (with handwheel)
• DN100 to 1000
• Without anti-cavitation cylinder

Storage instructions

Handling

The handling of the valve has to be made with care, in order to avoid any shock, even accidental, which could damage the coating. In particular during the lift of the valve chains, cables or ropes used for that specific operation must not be clamped or touch the shafts, the gearbox or its handwheel. Grab the valve by connecting the lift devices to the flanges or eyebolts (if present).

Storage

Valves are generally supplied with plugs at the extremities, or in pallets banded with plastic film; if the valves are without packing and have to stay for long time in the stock before being install, they must be stocked covering the passage of the valve, safeguarding in this way the interior parts and particularly the seat from the contact with powder or dirt. In absence of a right place the valves have to be wrapped with cellophane or rather dark plastic sheets.

The valves must be stored in a location offering a good protection from direct sun, rain and all other atmospheric agents (admissible temperature range: 0°C  50°C). Rubber parts and gaskets are light-sensible materials; in particular degradations may occur in case of sunlight exposition.

The valves must not weight on the shaft or on the gearbox, and if the valves have to be stacked in a pile, Is is suggested to avoid the contact between coated surfaces: a cardboard between the surfaces should be used.

Accessories and spare kits storage

1- Gasket

Normally rubber gaskets are sunlight sensitive. Therefore it is good practice to store rubber parts in sunlight protected areas, in order to avoid deteriorations. If such conditions are not available, rubber parts should be then at least protected with cellophane or rather dark plastic sheets.

2- Bolts

The requested flange bolting is normally packed in a sack or sent in box equipped with a tag indicating the number and the type of the packed bolts. It is absolutely necessary to keep them in the original condition of delivery, avoiding putting them in contact with material which could damage them. Generally the bolting is slightly lubricated before delivery; any contact with dirt or dust could, in extreme cases, damage the threads and eventually prevent its mounting.

3- Actuators

For this particular type of accessory, which is generally already mounted on the valve when delivered, it is necessary to pay attention that nobody, with the exception of the specialist or authorized people, could attempt to repair or manipulate it, this would take out any warranty covering these specific components. It is very important to check that the threaded orifices for the electric/hydraulic/pneumatic connections are always well protected with the original plugs until their use in final assembly. This will insure that no dirt, dust, humidity or any other external particle will damage the internal parts (gears, electrical coils, pistons, cylinders, seats, etc.). When the electrical wiring is not made immediately after the mechanical mounting of the valve in the pipe system, the installer/contractor will take the necessary measure to protect correctly and thoroughly the actuator against any atmospheric degradation and the built-up of condensation. Furthermore it is necessary to check periodically during this particular period of time the status of internal components, by removing the covers of the operative unit and of the reduction unit, protecting with silicone or oil vaseline the respective cover gaskets when remounting them.