Symbols Used; Definition Of Terms; Intended Area Of Use; Condition As Supplied To Customer - GEM 658 Installation, Operating And Maintenance Instructions

2.3

Symbols used

Danger - hot surfaces!
Danger - corrosive materials!
Hand: indicates general information
and recommendations.
Bullet point: indicates the tasks to
G
be performed.
Arrow: indicates the response(s) to
®
tasks.
Enumeration sign

3

Definition of terms

Working medium
The medium that flows through the
diaphragm valve.
Control medium
The medium whose increasing or
decreasing pressure causes the diaphragm
valve to be actuated and operated.
Control function
The possible actuation functions of the
diaphragm valve.
4

Intended area of use

The GEMÜ 658 / 688 diaphragm valve

is designed for installation in piping
systems. It controls a fl owing medium
by being opened or closed by a control
medium.
The valve may only be used providing

the product technical criteria are
complied with (see chapter 6

"Technical data").

Do not paint the bolts and plastic parts of

the diaphragm valve!
658, 688
Use the diaphragm valve only for the
intended purpose!
® Otherwise the manufacturer liability and
guarantee will be void.
Use the diaphragm valve only in
G
accordance with the operating
conditions specifi ed in the
contract documentation and in the
installation,operating and maintenance
instructions.
The diaphragm valve may only be used
G
in potentially explosive zones confi rmed
in the declaration of conformity (ATEX).
5 Condition as supplied
to customer
The GEMÜ diaphragm valve is supplied as a
separately packed component.
6 Technical data
Working medium
Corrosive, inert, gaseous and liquid media which have no
negative impact on the physical and chemical properties of
the body and diaphragm material.
The valve will seal in both flow directions up to full operating
pressure (gauge pressure).
Operating temperature
(dependent on medium wetted materials)
Control medium
Inert gases
Max. permissible temperature of control medium
Filling volume:
Diaphragm size
10
25
40
50
Ambient conditions
Max. ambient temperature
24 / 44
WARNING
max. 150 °C
lower piston upper piston
0.04 dm³ 0.03 dm³
0.08 dm³ 0.09 dm³
0.44 dm³ 0.47 dm³
0.44 dm³
0.47 dm³
60 °C
60 °C