RATIONING of FABRIC CONSUMPTION 

share of cost of fabric in the cost of ready-made garments accounts for 80 - 90%, therefore, the primary source of reducing the cost of production is to reduce the loss of fabric in production. 

In the garment industry following the loss of fabric: magicalia attacks, the loss of the width of the fabric, the irrational remains (not suitable for the manufacture of primary products) and loss (fervor) along the length of the deck.

When rationing of fabric, the main task is to establish advanced technical standards of fabric consumption for all manufactured products subject to the minimum loss of fabric in production, observing the scale of size and height and specifications cut. 

The dimension of the space of curves 

For the rational use of tissue is of great importance for the correct measurement of area of plane figures. Total tissue loss in production amount to 9 - 16%, while the proportion magically attacks against all losses reaches 80%.

To determine the correct results of the rational use of fabrics it is necessary to have the measurement data space patterns. In the garment industry dimension of the space of curves is not automated, since the measuring machines used in other industries, for example, to measure fur skins and leathers, not accurate enough (accuracy 3%). Such machines are not acceptable in the clothing industry where tenths of a percent of the tissues. 

In the garment enterprises, various methods of area measurement patterns. 

 Writing the details of the patterns in the area of the rectangle "reticulation". The simplest device for determining the area of a plane figure is the so-called "palette" (Fig. 148), which is a transparent plate or sheet of graph paper with lines drawn on them, square meshes in any unit area e.g., cm2. In the upper right corner of each square (25 cm2) indicates the size of the growing area from zero.

A pattern on graph paper so that it's possible to call one or two slices with bounding lines. Find the area of the rectangle ABCD occupied by pattern; calculate the area of squares enclosed by the outline rectangle and the outline of the measured part (up to 1 mm2). The difference between the area of the rectangle ABCD and the area of the attacks will be the area of the part.

 The Planimeter Harp. A kind of "mosaic" is the planimeter "LHA", which is a plate of transparent material coated with it at an equal distance from one another in parallel lines.

The length of the segments enclosed by the boundaries of the measured figures are determined by a measuring wheel or summing the compass, and then added together. While the curvilinear boundary rectified, i.e., each band is encased between a pair of parallel lines on the plate, restricted to segments perpendicular to them direct so that both of the triangle formed by these lines and the curve have the same area. The sum of the lengths of the strips to the distance between the parallel lines of the plate gives the desired area.

If measuring area by the planimeter "Harp" the number of calculations is reduced compared to the dimension of "palette". However, the process of measuring the areas addressed by the methods is imperfect and cumbersome. 

Used in our "Harp" the breakdown of the measured area into a number of strips of equal width, lies the Foundation of most modern cars for area measurement. 

 The note. A planimeter - a device that rim contour of a plane figure to determine its area. The value area shows the drum of the counting wheel. The first planimeter, still in use today, were invented we have P. A. Zarubin, in 1854, 

At present, distinguish the note a few designs, but they are divided into two groups: polar and rectilinear. In turn, note these groups are divided into ordinary and precision. 

Straight note convenient when measuring long, but narrow space; precision allow to obtain higher measurement accuracy.

Measurement of areas with planimeter is not objective, since the accuracy of the measurement largely depends on the skill and integrity measures, as well as the state of the surface patterns. The measurement process is very time-consuming. 

 The calculated method. The area of the curves defined by the above-mentioned methods rely on groups size and height. In each group make measurements of the square patterns in two adjacent sizes of the same growth, for example, 46 (3 growth) and 48 (3 growth); 52 (3 growth) and 54 (3 growth). The area of the curves other sizes find design method according to the increment of the area of the curves between adjacent sizes. Then just do the measurement of the square patterns for each size of two adjacent growth. For example, 44 (2 growth) and 44 (3 growth), 48 (2 growth) and 48 (3 growth), etc.Square patterns the other Rostov determine the settlement increment of square patterns between adjacent growth within the same size.

This method of calculation gives the opportunity to find out the increment of the square patterns from size to size and from growth to growth. 

The above-mentioned methods of area measurement of the patterns is very time consuming for measuring the area of one set of patterns, such as men's suit, takes 21 - 23 h

 Dimension of the space of curves with the help of photoelectron machines. In 1960 in Leningrad was developed by a working draft (modeled photoelectronic machine IMASH-2) and made the first sample of photoelectron machines IL (Fig. 149) for area measurement of the patterns in the garment industry; currently arranged their serial release.

Labor productivity when measuring the area of patterns on photoelectric machine of the SLUDGE is increased 6 - 7 times compared with the performance of the above methods, the error in the measurement of different component dimensions is: for large parts +-0,5...+-0,25%, for small parts +-1%. On average, the inaccuracy of the measurement area of the set of patterns does not exceed 0.5%. the

Technical characteristics of the car IL 

dimensions, mm: 
length with extended carriage... 3750 
width..................................... 1272 
height .................................... 1138 
Mass (weight), kg .......................... 500 
the duration of the measurement patterns the largest area, with 60...

The XP machine IL for area measurement of the patterns used photoelectronic device. On the machine with the aid of the light beam can be reduced to the counting area to count the pulses produced by the generator during the dimming of the light beam moving patterns. The measured pattern is placed on a transparent surface cover, light lamp and flow over the arc gap. When promoting above the arc slit pattern as if is divided successively on the elementary square, which counts electronic counter.At the time of exit patterns beyond the arc gap circuit is opened and the account is terminated.

On the machine simultaneously in a single pass of the table lid can be consistently measured a few areas of fine detail. After measuring a complete set of templates car check twice the dimension of the square test pattern.