SU975765A1 - Method for making drafting sticks - Google Patents

Description

(54) METHOD OF MANUFACTURING DRAWING RODS

The invention relates to the manufacture of drawing rods from natural materials for artistic drawing. There are known methods for making drawing rods (souss), by pressing or rods from a powder mixture of chalk and coal f1. The lack of a sousse is its fragility, which is why it dusts during drawing and does not hold well on paper. In addition, the method of manufacturing souss is relatively complicated, since it involves labor-intensive operations: powder manufacturing, mixing and pressing. The closest to the invention to the technical essence and the achieved result is the method of making drawing rods by crushing and heating the original natural material (dry wooden sticks) in a layer of sand C 2). The disadvantages of the rods thus obtained are their greater brittleness and poor adhesion to drawing paper, cardboard and other materials. The purpose of the invention is the manufacture of drawing rods with improved physical and mechanical characteristics. This goal is achieved by the fact that according to the method of making drawing rods by crushing and heating the raw material in the sand layer, dictyonem slate is used as the raw material, and the heating is carried out in two stages: first at 100-120 ° C and then at 450 -550 ° C until the emission of flue gases stops. In the manufacture of rods, the lower heating temperature (450 ° C) is determined by the start of heating and charring of the dictationaeum slate, and the upper temperature (550 ° C) by the start of intensive combustion of the organic structure of the shale. By adjusting the temperature of the yarn, drawing rods can be obtained within the tones from the on-square of the J t to the dark brown and black, E depending on the properties of the natural diamond shale, you can also get rods with a grayish tone and in some cases with a gray tone. Initial warming at 100-120 ° C is necessary to remove gsody and pieces of dictationamic slate. Heating the pieces of shale in the sand is necessary to prevent their destruction, since the sand on the surface of the shale counteracts the pressure of the gases emanating from it. In the sand layer, the gases exit the shale through microcracks without their expansion and thus do not destroy the pieces. Warming up dictichem shale pieces is necessary to remove crystal water and decompose the organic part (in the form of flue gases). Pieces of slate can be kept at that heating temperature for a long time even after the cessation of flue gases has ceased, provided that there is no contact between the air supply units. Otherwise, complete combustion of the organic structure and carbon of the shale begins. The cessation of flue gases evidences the necessary degree of removal of crystal water and the organic part (in the form of flue gases). The time until termination of the flue gas emission is determined by the size of the pieces and the number of them in the heating volume. The mineral part of dictionam shale has the following chemical composition,%: siOs 5O; 13; FeO 2.5; RegOz 1; FeS24; GaO 0.5i (O

8,8

0.22

2.16 2.45

7.9 0.25 2.55 .0.26

7.9 0.25 2.45 8.8 2.75 0.28

1O, 4

6,510,5

8.09.5

8.28.9

8.86.0

3.58.8 0.5; KjO 6.5; 0.2; PjOj- O, 1; TiOj 0.3; V2O5-O, 06; Oz1,1. 2 const organic part 2%. The organic part contains the following components,%: C 70; H 6.5; 5 1.6; N 2; О + СЯ 2О. Example. Pieces of dictionaeum shale, 0.5-5 kg in size, are heated at 1OO 15 ° C, set into a layer of fine sand so that they form a layer of sand 1X) 12-15 cm long. Then they are heated at 450 ± 5 ° C until it stops. The emissions of fumes are 1 / x gases and leave to stand in a layer of sand. From the obtained pieces, brown drawing rods are cut, Pr and m 2. Dictational shale pieces of size 0.5-5 kg are heated to “p„ llOf 5 ° С, set; fine sand is hung in such a way that a layer 12-15 cm thick Jm and j. .LJ, see shale, then heat the psi 5 Г i owij, j i .. until the flue gas termination stops, the smoke of the smoke of the callings is left to cool in the ii.Baic layer in UJIUL, ica. Dark brown drawing rods are cut out of the obtained pieces. PRI me R. 3. Pieces of dictionaeum shale, 0.5-5 kg in size, are heated up at 120 ± 5 ° C, set into a layer of sand and heated at 55 ° T .5 ° C until flue gases are released. The drawing rods cut after cooling in the sand layer have a black and dark brown color. Data on bending strength and hardness of the obtained rods in dependent-. These sizes of rods in comparison with the known are presented in Table 1 and 2.

Table

The hardness of the rods (according to the Rockwell method, the load is 60 kgf) The rods obtained by the proposed method are durable, do not soil hands, do not crumble when drawing, and do not scrape the paper. The intensity of the color of the image does not vary with time. These rods can be used in various configurations and sizes. The most common rod size is 50x50x1-10 mm. It is possible to use rods with a toothed tip, with d1L11formed edges, etc. When placed under a paper (or cardboard) soft substrate or a substrate with a patterned relief, you can get a peculiar

Claims (2)

images. The proposed storges give good adhesion to paper, the expressive texture of the pattern, have improved physicomechanical indicators, and can also be used as black chalk on a white board. Formula of the invention The method of making drawing rods by crushing and heating of the original natural material in a sand layer, characterized in that, in order to manufacture rods with improved physicomechanical characteristics, dictynemic slate is used as the original natural material stages: first at 100-120 ° C and then at 45 ° -55 ° C until the emission of flue gases stops. Sources of information taken into account in the examination, 1. (O., joonestoimise ja moaeimise opik. Gesti Nsv Kunst j TqK .inn, 1963, p. 11, column 2, paragraph 5, 2. In the same place, column 2, paragraph 3 (prototype).