Main proportion
60 to 100 %
Medium sieve nominal mesh
width
mm
2.8
5.6
11.2
Percentage of fines
(incl. finest woodchips)
max. 20 %
Fine sieve nominal mesh width
mm
1
1
1
Definition of woodchip size classification according to QM-Holzheizwerke [quality management for wood
heating plants] regulations and EN 14961
Woodchips or shredded wood
P16
P45
P63
P100
P300
Main fraction
> 80 % of mass
mm
≥ 3.15
≤ 16
*2
≤ 45
≥ 8
*2
≤ 63
≥ 11.2
*2
≤ 100
≥ 3.15
≤ 300
Percentage of fines
< 5 % of mass
mm
< 1
< 1
< 1
< 1
< 1
Coarse percentage
Max. particle length
< 1 % of mass
mm
> 45
all < 85
> 63
> 100
> 200
> 400
Maximum length
mm
–
125
*2
200
*2
250
*2
–
Woodchip requirements
For combustion in the Vitoligno 300-H, use woodchips with a maximum
coarse percentage of 20 %, a maximum cross-section of 5 cm
2
and a
maximum length of 12 cm (5 % up to 16 cm) (G50/P45).
The water content of the woodchips can be up to 30 % (w30/M30).
Bulk density S (kg/m³), water content w (%), size G (mm) as per ÖNORM M 7133
and to QM-Holzheizwerke
See note
S 130
w10 to w20
G30/G50
P45/P63
Natural sawdust
S 130
< w15
G30/G50
P45/P63
Dry, mixed shavings, woodchips from wood remnants
S 200
< w15
G30/G50
P45/P63
Dry, mixed shavings, woodchips from wood remnants
S 200
w20
G30/G50
P45/P63
Soft natural woodchips
S 200
w20 to w35
G30/G50
P45/P63
Natural sawdust
S 250
< w15
G30/G50
P45/P63
Dry, mixed shavings, woodchips from wood remnants
S 250
w20 to w35
G30/G50
P45/P63
Soft natural woodchips
S 300
w20 to w35
G30/G50
P45/P63
Soft/hard natural woodchips
S 350
w20 to w35
G30/G50
P45/P63
Hard natural woodchips
Note
With coarse content limitation < 1 % to a length of up to 125 mm
Fuel
Poured weight
S (kg/m
3
)
Max. size (mm) to
Max. water
content
w (%)
ÖNORM M 7133
EN 14961
See note
Dry, mixed natural sawdust, woodchips from wood remnants
S 130 - S 200
G30/G50
P45/P63
w10 - w20
Briquettes from wood remnants, diameter 40 to 60 mm
S 200 - S 350
G30/G50
P45/P63
w10 - w20
Soft natural woodchips
S 200- S 250
G30/G50
P45/P63
< w20
Soft/hard natural woodchips
S 300 - S 350
G30/G50
P45/P63
w20 - w35
Soft/hard natural woodchips
S 300 - S 400
G30/G50
P45/P63
w20 - w50
Note
With coarse content limitation < 1 % to a length of up to 125 mm
Quality characteristics
Good woodchips:
■ As per ÖNORM M 7133
■ Size G30 or G50
■ Max. 5 % anomalies
■ Smooth surfaces
Low quality woodchips:
■ Frayed surface
■ More than 5 % anomalies
■ Coarse percentage > 20 %
■ Greater than G30 or G50
*2
Values to QM-Holzheizwerke differ from those of EN 14961
Principles of wood combustion
(cont.)
8
VIESMANN
VITOLIGNO 300-H
1
5672 507 GB