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| Common
Names: |
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Limba
Afara
Ofram
Akom
Frake
Korina
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- Mechanical Values
| Category |
Green |
Dry |
Units |
| Weight |
|
34 |
lbs/cu.ft. |
| Density
(air-dry) |
|
34 |
lbs/cu.ft. |
| Specific
Gravity |
0.38 |
0.45 |
|
| Hardness |
|
490 |
lbs |
| Stiffness |
770 |
1010 |
1000
psi |
| Bending
Strength |
6000 |
8800 |
psi |
| Shearing
Strength |
|
1410 |
psi |
| Max.
Crushing Strength |
2780 |
4730 |
psi |
| Work to
Maximum Load |
8 |
9 |
in-lbs/in3 |
| Radial
Shrinkage (G->OD) |
|
4 |
% |
| Tangential
Shrink. (G->OD) |
|
6 |
% |
| Volumetric
Shrink (G->OD) |
|
11 |
% |
Environmental Profile
This species is reported to be relatively secure, with
little or no threat to its population within its natural
growth range (Source - World Conservation Monitoring
Center - 1992 ).
Distribution
The species is reported to be widely distributed from
Guinea to Angola and Zaire. It grows in the rain and
savannah forests, and is reported to be a good
plantation species in West Africa.
Product Sources
Supplies are reported to be plentiful and the material
is available in the form of veneers and lumber. Price is
reported to be in the moderate range.
The following species in the database has been suggested
as a substitute for Ilomba for some end uses:
Ako (Antiaris africana
A. welwitschii )
African pterygota (Pterygota bequaerti
P. macrocarpa )
Brown terminalia (Terminalia brassii )
Tree Data
The tree is reported to attain heights of 150 feet (46
m) at maturity, with trunk diameters of 4 to 8 feet (1.2
to 2.4 m) above broad plank-like buttresses. The tree
develops boles that are often straight, well-developed
and clear of branches to about 90 feet (27 m).
Heartwood Color
Limba on the commercial market is reported to be either
of two colors: uniformly cream, pale yellow or grayish
brown sometimes with nearly black, irregular streaks
which give the wood an attractive appearance. Sapwood
and heartwood are not clearly differentiated.
Grain
Grain is reported to be straight to irregular or
interlocked.
Texture
Texture is moderately coarse.
Luster
Wood surface is reported to have a high, satiny luster.
Odor
The wood has a mild odor, but no distinct taste.
Ease of Drying
The material is reported to dry readily and rapidly with
little or no degrade.
Drying Defects
Shakes and splits are reported to be common during
air-seasoning. Kiln-drying is often accompanied by
minimal checking and warping.
Kiln Schedule
T10 - D5s (4/4); T8 - D4s (8/4) US
Schedule J (4/4) United Kingdom
Movement in Service
Sesoned material is reported to be dimensionally stable,
with only small movement in use.
T/R Ratio
1.50
This indicator is more meaningful if it is used together
with other drying information and actual shrinkage data
in the tangential and radial directions. (Refer to the
Numerical Values window).
Natural Durability
The heartwood is reported to have little or no
resistance to decay. It is readily attacked by termites,
ambrosia beetles, and powder-post beetles. Felled trees
require special preventive care to protect the heartwood
against deterioration.
Resistance to Impregnation
Heartwood is reported to be resistant to preservative
treatment. Preservative penetration and retention in the
sapwood are reported to be adequate.
Toxic Constituents
Wood splinters are reported to cause inflammation of the
skin in some individuals.
Veneering Qualities
The wood is reported to be very suitable for veneering,
and the figured black heartwood is reported to be highly
favored for decorative veneers for paneling and
furniture.
Blunting Effect
Dulling effect on cutting edges is reported to be
slight.
Resistance to Cutting
The wood is reported to saw easily.
Planing
The wood is reported to work readily. It responds well
to ordinary machining tools in all operations, and works
to produce clean smooth surfaces.
Gluing
Gluing properties are reported to be satisfactory.
Nailing
Pre-boring is required since the wood has a tendency to
split.
Screwing
Screwing is reported to require pre-boring.
Staining
The wood is reported to take stains readily.
Polishing
Polishing qualities are reported to be excellent after
filling.
Response to Hand Tools
The wood is reported to work readily with hand tools.
Steam Bending
The wood is reported to have poor steam bending
properties.
Strength Properties
Strength properties of the timber are sometimes reduced
considerably by the presence of brittleheart. The wood
is weak and is reported to be rarely used in
applications where strength is of major concern. Bending
and crushing strengths in the air-dry condition (about
12 percent moisture content) are low. It is not hard,
and has moderate weight and density.
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