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Directions for use air operated needle valves
Type NV ... - 08 - 8B - ATC / - ATO
1. General safety and warning rules
Adherence to the specifications and observance of the instructions is paramount for correct functioning and has therefore definitely to be assured by the user.
Local environmental conditions should also be taken into account. The competent and tight make-up of this connection is directly dependent on the experience
of the user/technician. Care must be taken that all users/technicians are trained thoroughly in the competent and correct handling/assembly of these connections.
NOVASWISS high pressure components have been designed acc. to the normes and regulations for pressure vessels and AD files. If the components are ordered
in degreased conditions, make sure that no contamination happens during the mounting. If the components are being used in explosion proof environment make
sure to use only explosion proof tooling.
2. Functional description and correct use
NOVASWISS air operated needle valves serve for the pressure-tight blockage of media in either directions.
No changes (e.g. mechanical alterations, welding, brazing, delete the markings, soldering etc.) may be made to the valve. Do not use
products which are damaged or have been subjected to high temperature (ex. in case of fire). If the valves are used for purposes other than
those intended, the manufacturer or vendor shall not be held liable for any resulting damage. Such risks shall be borne by the user alone.
3. Specifications
3.1 Valve
Table 1
NV...-08-8B -ATC / -ATO
Pressure range at
0...8'000 psi
-50°C...+30°C
0...550 bar
Pressure range at
0...6'240 psi
+30°C...+200°C
0...430 bar
Pressure range at
0...5'440 psi
+200°C...+300°C
0...375 bar
Temperature range of the media
-50°C...+200°C (for a short time till +300°C)
When using media that cause corrosion, mechanical changes (e.g. solid particles etc.), as well as chemical
destruction (e.g. H2So4, H2, O2 etc.) the user must take appropriate countermeasures (e.g. explosion
Media (fluids)
protection etc.) and if necessary examine and/or replace the parts regularly.
In the case of flammable, explosive and/or toxic media, the applicable statutory regulations must be
observed.
The air operated needle valves are designed predominately for static service duty.
Type of service
In the case of dynamic loading appropriate measures must be taken by the user.
Ambient temperature
-50°C...+65°C
3.2 Air operator
Table 2
-ATC (Air to close)
Max. working pressure
Operating pressure
The optimal opeating pressure is indicated on the name plate of the air operator.
Medium
Use filtered air, without oil. Recommended micron rating of filter: max. 40mm
Temperature range of the compressed air
Air inlet
Vent filter
Ambient temperature
4. Installation
Table 3
Druckanschluss
① Indicator
Raccord de pression
-4... / -6... / -8... / -9...
Pressure connection
② Air operator
Ød [mm / inch]
6 / 0.24
③ Air inlet; thread G 1/8"
H
[mm / inch]
10 / 0.39
④ Mounting holes
⑤ Pressure connections
F
[mm / inch]
35 / 1.38
⑥ --
⑦ --
Fig. 1
⑧ Vent holes for the packing
⑨ Grub screw
⑩ Bonnet
Fig. 3
ATO
Fig. 2
①
ATC
②
③
⑩
④
⑨
⑧
⑤
4.1 Installation of valve
1. Mount valve using mounting holes
2. Connect the air tubing with a suitable fitting on the air inlet
3. Check if the grub screw is tightened firmly.
4. Make sure that the vent holes are never obstructed!
5. When used in a explosion proof zone, remove air filter
tube.
Needle valve are bi-directional and can be installed in either position.
In applications with a high flow rate or as a discharge valve we recommend that the flow direction as per the Fig. 4 be selected:
Fig. 4
FLOW
4.2 The following pressure connections are admissible: -...B
4.2.1 British Standard Pipe connection -...B
1. Slide seal ring onto adaptor thread.
2. Screw adaptor into connection bore and tighten down according to the adaptor manufacturer's instructions.
4.3 Flow chart for air operator
(not included in the delivery)
Fig. 5
ATO
-ATO (Air to open)
③
100 psi / 6.9 bar
-15°C...+65°C
G 1/8"
1/8" BSPP
-25°C...+65°C
①
②
⑩
③
⑨
④
⑧
⑤
© 08.2018 / Rev. 3
Copyright by NOVA Werke AG
④
. Valve can be mounted in any orientation.
③
.
⑪
. Exiting air must be conducted to a explosion free zone by means of a leek proof
FLOW
FLOW
Fig. 6
ATC
③
NV_08_8B_ATO/ATC Imp
5. Operation
5.1 Operation ATC (Air To Close)
To open:
-Release the actuating pressure.
To close:
-Apply actuating pressure.
5.2 Operation ATO (Air To Open)
To open:
-Apply actuating pressure.
To close:
-Release the actuating pressure.
5.3 Warning
-
Opening too fast can cause pressure hammer in the system and consequential damage to connected equipment. Excessively fast opening is
therefore to be avoided.
-
Outside the temperature range 0°...+40°C, protective gloves have to be used.
-
If the high or medium pressure connections are to be subject to intense vibration, then the use of anti-vibration connections is required.
Order number according to NOVA-Catalogue.
-
Should the components be mounted against a flat surface, it must be assured that at least one vent hole on every port (and vent hole for the
packing ⑧ ) is left uncovered. It is forbidden to cover or plug vent holes.
-
Only dry compressed air, free of oil or grease must be used.
-
If the actuator is used in a humidenvirement, it must be assured, that no humidity enters the actuator. Periodic checks for rust inside and
outside must be made to assure proper functioning.
-
The closing and opening times must be set by external chokes (not included in the supply). This is an important factor for life duration. Our
products are designed for a maximum service life of 10 years.
6. Disassembly
Check that there is no pressure left inside the valve and the air operator before disassembly!
To disassemble, proceed in reverse order to assembly.
7. Maintenance
7.1 Servicing
NOVASWISS NV 1 / 2 / 3 - ...-...-ATC/-ATO air operated needle valves must be checked periodically for leaks.
Should components need replacement, only original NOVASWISS spares must be used.
7.2 Repair
Repair work may only be performed according to the repair instructions by instructed technicians.
For example:
- Changing the replaceable seat
- Changing the packing and stem
7.3 Troubleshooting
Fault
Possible cause
Remedy
-Control fault.
-Check pneum. air system.
Valve does not close.
-Damage to seat and/or stem.
-Consult technician.
Valve does not open.
Control fault.
-Check pneum. air system.
ATC:
-Packing gland loose.
-Release system pressure
-Release air pressure, to avoid pressure of lower stem on seat.
⑨
-Loose the grub screw
Tighten the grub screw
Media leakage at
⑧
ATO:
packing vent hole
.
-Release system pressure
-Open valve with air pressure, to avoid pressure of lower stem on seat.
-Loose the grub screw
⑨
Tighten the grub screw
-Release air pressure.
-Damage to packing and/or stem.
-Consult technician.
Table 5
Valves
8 kpsi
Connection
1/2
⑩
Bonnet
Ma [Nm]
25
8. Disposal
At the end of its service life the valves are to be disposed in accordance with the national regulations.
Specifications are subject to change without notice.
NOVA WERKE AG
www.novaswiss.com
Vogelsangstr. 24
info@novaswiss.com
CH-8307 Effretikon
Tel: +41 (0) 52 354 16 16
3 / 3
Switzerland
Fax: +41 (0) 52 354 16 90
⑩
, tighten down the bonnet
to the torque given in the table 5.
⑨
.
, tighten down the bonnet
⑩
to the torque given in the table 5.
⑨
.
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