When designing various kinds of wooden structures, they often use such an indicator as the weight of those lumber from which they are supposed to be made. It would seem that such information can be obtained from specialized directories. However, in such literature, unfortunately, often only the weight of 1 m 3 of a bar or, for example, a board is often indicated. Lumber is often purchased not by cubic meters, but simply by the piece.
The length of the timber sold by woodworking workshops can be different. But most often, such enterprises sell sawn timber 6 m to the population. So what, for example, can be the weight of a bar of natural humidity 150x150x6000 mm? To find out, you will have to make some simple independent calculations.
What determines the weight of lumber
It is clear that the more moisture is contained in the timber, the harder it will be. However, the weight of such lumber depends not only on this factor. Performing the calculations, in this case, the characteristics of the actual wood species itself must be taken into account. Indeed, for example, an oak beam in any case will be heavier than lumber from birch.
What is natural humidity?
So, how do you calculate the weight of a wooden beam of natural humidity 150x150x6000 mm of a particular breed? Making such calculations is actually not too difficult. However, before proceeding with the calculations, it’s still worthwhile to decide on the concept of “natural humidity”.
In construction and in the manufacture of various products, only wood with a moisture content of not more than 12-15% is used. And even such boards and timber before use in most cases are additionally dried for some time.
Humidity only sawn wood will, of course, be very high. In any case, its indicator will exceed 12-15% significantly. It is such humidity that is commonly called natural. That is, we ultimately need to find out the weight of a wooden bursa of standard length with a section of 15x15 cm, made of freshly sawn wood.
We take into account the breed
The basis for such an operation should be taken from the table of weight of lumber in cubic meters.
Perform calculations in this case as follows:
recognize the number of bars of a given length and section of 1 m 3 ;
by simple division, the mass of one such unit of lumber is calculated.
One cubic meter of timber, measuring 150x150x6000 mm, will thus contain 1: 0.15: 0.15: 0.15: 6 = 7.4 pieces. To find out the weight of a beam, in this case you need:
For example, at a moisture content of 15%, 1 m 3 of pine lumber weighs, according to the table above, 440 kg. That is, the calculation in this case will look like this:
It is also easy to determine that the beam weight of 150x150x6000 mm from a larch of the same humidity will be 90.5 kg. For aspen, this figure will be 67.6 kg.
Instructions for calculating the weight of a bar of natural humidity 150x150x6000 mm
Thus, the weight of lumber of a given moisture content is not too difficult to determine. To do this, you just need to solve two simple mathematical examples. But what will be the weight of a bar of natural humidity 150x150x6000 mm? In order to determine this, among other things, you need to know the actual last indicator for a particular type of wood.
You can also get such information from special tables. So, for example, the natural humidity of pine is 60-100%, larch - 50-70%, birch - 70-90%. These parameters should be taken in this case to calculate the weight. For obvious reasons, exact calculations will not be possible.
So, how much does a timber weigh 150x150x6000 mm of natural humidity? Based on the data in the table above:
pine beams of such dimensions will weigh from 580 / 7.4 = 78.3 (60%) to 730 / 7.4 = 98.6 (100%) kg;
the weight of a bar of natural humidity 150x150x6000 mm from larch will vary from 820 / 7.4 = 110.8 kg to 930 / 7.4 = 125.7 kg.
In the same way, you can calculate the beams of such dimensions of natural humidity for any other breed.
Specific gravity
There are only two types of wood density:
Above, we considered a method for determining the volumetric weight of timber 150x150x6000. Natural humidity or the set value in such calculations is an important indicator. Indeed, in this case, the weight also depends on the amount of moisture contained in the wood structure. But if desired, the specific density index can be calculated for the beams.
This can be done using the table above. Calculations in this case will be carried out without taking into account humidity. That is, to calculate, you need to find the number of beams of a certain size in a cubic meter and simply divide the indicator from the table by the resulting number.
Thus, for pine 520 / 7.4 = 70.3 kg is the specific gravity of the beam 150x150x6000. Natural humidity - permissible operational or some other - in this case are not taken into account.