4.9 Burn-back protection devices (RSE)
Note
In wood processing operations, 2 burn-back protection devices con-
nected in series are required.
For example 2 rotary lock valves or 1 rotary lock valve in combina-
tion with a shut-off gate valve.
Rotary lock valve
For part no., see pricelist
Rotary lock valve for fire-safe separation of the combustion system
from the fuel store with positive pressure, and with simultaneous
material transportation for installation in a drop section. The rotary
valve is made entirely from steel and is permissible as fire protection
between the combustion system and woodchip silos in wood pro-
cessing operations with positive pressure. The drive device is a spur
geared motor with sprung torque support. If the woodchips are
extremely coarse, reversing the direction of rotation of the rotary lock
valve avoids jamming.
Fire safety: RSE to TRVB H-118
Max. permissible positive pressure in the fuel store: + 500 Pa
Max. permissible negative pressure in the fuel store: ± 0 Pa
Standard delivery:
■ Rotary lock valve as per order data
■ Activation of spur geared motor for both rotational directions
according to boiler control unit
Positioning:
■ Directly above the feed screw conveyor
■ Exception for funnel discharge: Directly at the discharge
Application:
MZ 260:
■ Use only with fuels up to max. P16S to EN ISO 17225-4 and a
conveyor device with a diameter of 150 mm or 190 mm
MZ 340:
■ Use only with fuels up to max. P31S to EN ISO 17225-4 and a
conveyor device with a diameter of 190 mm or 250 mm
Dimensions of rotary lock valve
d
e
f
c
øb
a
Trade name
Rotary lock valve
Type
MZ 260
MZ 340
a
mm
330
412
b
mm
7
264
7
340
c
mm
709
689
d (Di)
mm
202
204
d (Da)
mm
250
250
e (Di)
mm
202
222
e (Da)
mm
250
272
f
mm
346
434
Drive rating
kW
0.75
0.75
Drive speed
rpm
25
25
Shut-off gate valve MA 220
For part no., see pricelist
Fire safety-tested device for installation in a drop section, for
mechanical separation of combustion system from unpressurised
fuel store. The shut-off gate valve is opened by a motor and closed
by spring balancer with zero current in the event of burnout, risk of
burn-back or power failure.
Material:
Steel
Drive:
Spring return motor
Fire safety:
RSE to TRVB H-118
Standard delivery:
■ Shut-off gate valve as per order data
■ Activation of shut-off gate valve according to boiler control unit
■ Spring return motor (torque 30 Nm)
Note
In wood processing operations, 2 burn-back protection devices con-
nected in series are required (e.g. 2 rotary lock valves or one rotary
lock valve in combination with a shut-off gate valve).
Installation accessories
(cont.)
40
Viesmann
VITOFLEX 300-UF
4
5682428
