Siemens VRD Series User Manual

Technical Instructions VRD4 Series Double Valves
Document Number CC1N7649us
September 08, 2016
Page 4 Siemens AG Building Technologies Division
Specifications
Approvals
Agency approvals/standards UL/429, FM/7400,
CSA/ANSI Z21.21/CSA 6.5 C / I
Commercial/industrial
IRI approvable
Agency marks apply only for VRD40.xxxU series
gas valve bodies assembled with SKPxx.xxxUx
actuators.
Operating
environment
Maximum operating pressure See Table 2
Maximum back pressure (differential) 4 psi (300 mbar)
Close-off pressure See Table 2
Permissible gases See Type of gases and Use
Permissible gas temperature 14 °F to 140 °F (-10 °C to 60 °C)
Permissible operating temperature 14 °F to 140 °F (-10 °C to 60 °C)
Use
Functionally, the valves correspond to Siemens gas valves in accordance with UL 429.
They are designed for use with slightly aggressive and dry gases
- Maximum 140 °F (60 °C)
- Gases like biogases, digester gases, process gases, natural gas or air
The valve is used as:
- Shutoff valve (in connection with SKP15...)
- Control valve with shutoff function (in connection with SKP25..., SKP5… or SKP7…)
For SKP... with pressure regulation function (SKP2..., SKP5... and SKP7...) is recommended
to review with Siemens with regard to suitability with the relevant type biogases.
The chemical composition and aggressiveness of each type of biogas or recycling gas is
different, not constant and depends on several factors.
Aggressiveness of the gas against valve materials augments especially
- as the hydrogen sulfide content H2S increases
- as the moisture content and the temperature of the gas increases. Condensation in the
valve is not permitted.
The user must decide after consultation with Siemens whether the valve materials are suited
for the relevant type of gas.
The composition and concentration of the gas components may vary.
It is therefore impossible to provide a guarantee regarding life expectancy.
The suitability in principle is based on tests carried out on the gases to be used.
With VRD40.xxxUx valves in biogas applications. It is recommended to
- install a valve proving device / sequence
- leak test the valves at 6- to 12-month intervals
- install SKPx5... with POC

Siemens VRD Series Specifications

General

Brand	Siemens
Model	VRD Series
Category	Control Unit
Language	English