ARI Armaturen STEVI AS 350 DN15-50 User Manual

Operating and installation instructions

Y-pattern processing valve - STEVI®AS 350

DN 15 - 50

Contents

1.0 General information on operating

instructions ..................................................2-2

2.0 Notes on possible dangers.........................2-2

2.1 Significance of symbols ...................................... 2-2

2.2 Explanatory notes on safety information ............. 2-2

3.0 Storage and transport ................................ 2-2

4.0 Description...................................................2-3

4.1 Scope of applications .......................................... 2-3

4.2 Operating principles ............................................ 2-3

4.3 Diagram............................................................... 2-5

4.4 Technical data ..................................................... 2-5

4.5 Marking ............................................................... 2-6

5.0 Installation....................................................2-7

5.1 General notes on installation............................... 2-7

5.2 Requirements at the place of installation ............ 2-8

5.3 Installation instructions concerning actuators ..... 2-8

5.4 Installing valves with butt weld ends ................... 2-8

Series 350

6.0 Putting the valve into operation ................ 2-9

7.0 Care and maintenance................................ 2-9

7.1 Replacement of bonnet ....................................... 2-9

7.2 Tightening torques ............................................ 2-10

8.0 Troubleshooting ........................................ 2-10

9.0 Troubleshooting table ............................. 2-10

10.0 Dismantling the valve or the top part.... 2-11

11.0 Warranty / Guarantee .............................. 2-11

12.0 Manufacturers declaration ..................... 2-12

13.0 EC declaration of conformity (ATEX) .... 2-13

Rev. 0040322000 3413 englisch page 2-1

Operating and installation instructions

®

Y-pattern processing valve - STEVI

AS 350

1.0 General information on operating instructions

These operating instructions provide information on mounting and maintaining the fittings.
Please contact the supplier or the manufacturer in case of problems which cannot be
solved by reference to the operating instructions.

They are binding on the transport, storage, installation, start-up, operation, maintenance
and repair.
The notes and warnings must be observed and adhered to.

- Handling and all work must be carried out by expert personnel or all activities must be
supervised and checked.

It is the owner’s responsibility to define areas of responsibility and competence and to
monitor the personnel.

- In addition, current regional safety requirements must be applied and observed when
taking the fittings out of service as well as when maintaining and repairing them.

The manufacturer reserves the right to introduce technical modifications at any time.
These operating instructions comply with the requirements of EU Directives.

2.0 Notes on possible dangers

2.1 Significance of symbols

ATTENTION !

. . .

Warning of general danger.

2.2 Explanatory notes on safety information

In these operating and installation instructions dangers, risks and items of safety
information are highlighted to attract special attention.

Information marked with the above symbol and “ATTENTION ! ” describe practices, a
failure to comply with which can result in serious injury or danger of death for users or third
parties or in material damage to the system or the environment. It is vital to comply with
these practices and to monitor compliance.

All other information not specifically emphasised such as transport, installation, operating
and maintenance instructions as well as technical data (in the operating instructions,
product documentation and on the device itself) must also be complied with to the fullest
extent in order to avoid faults which in turn can cause serious injury to persons or damage
to property.

3.0 Storage and transport

ATTENTION !

- Protect against external force (like impact, vibration, etc.).

- Valve mountings such as actuators, handwheels, hoods must not be used to
take external forces, e.g. they are not designed for use as climbing aids, or as
connecting points for lifting gear.

- Suitable materials handling and lifting equipment should be used.
See catalog sheet for weights.

- At -20 °C to +65 °C.

Page 2-2 Rev. 0040322000 3413

Operating and installation instructions

Y-pattern processing valve - STEVI

®

4.0 Description

4.1 Scope of applications

Valves are used for „interrupting the flow of liquids, gases and vapours in chemical,
processing, and other plants“.

ATTENTION !

- Refer to the data sheet for applications, limits on use and possibilities.

- Certain media require or preclude the use of special materials.

- The valves are designed for standard operating conditions. If conditions exceed

these requirements, e.g. aggressive or abrasive media, the operator should
state the higher requirements when ordering.

The information complies to the Pressure Equipment Directive 97/23/EC.
It is the responsibility of the machine planner to ensure compliance.
The special markings on the valve must be taken into account.

Refer to the catalogue sheet to see which materials are used in standard versions.

AS 350

Please contact the supplier or the manufacturer if you have any questions.

STEVI AS350 with actuator of plastic ATG:

For application of the valves in systems of device group II
category 2 acc. to Directive 94/9/EC, the valves are
equipped with a dust filter and an indicating label. The
maximum medium temperature is +85°C.

Marking: II 2 GD c IIB T6

To prevent the build up of static electricity, plastic valve
components must be wiped with a damp cloth.

4.2 Operating principles

A Y-pattern seat in the body will be closed by a plug, depending on the flow direction with or
against the media. The plug is connected with the piston via stem. The stem is sealed
within the guidance area between the valve body and control cylinder. The valve is actuated
with a piston via control pressure (air).

Rev. 0040322000 3413 Page 2-3

Operating and installation instructions

Connection 1

Spring closes /
Air supply pressure

opens

Connection 2
Spring opens /
Air supply pressure

closes

Connection 1
Air supply pressure opens

Connection 2
Air supply pressure closes

Y-pattern processing valve - STEVI

Depending on application different types are possible:

®

AS 350

1. Spring closes on air failure (NC)

Fig. 1:
When applying pressure, the air supply
pressure moves the piston against the
spring, lifts the plug from the seat and the
valve opens.

2. Spring opens on air failure (NO)

Fig. 2:
In the rest position, the valve is held by a
spring below the piston in the open position.
The valve closes by introducing the air
supply pressure.

3. Double acting (DA)

Fig. 3:
There is no sping installed in the actuator.
The valve opens and closes only by air supply pressure

Page 2-4 Rev. 0040322000 3413