The calculation unit of fabric density of pvc tarpaulin is in metric system, which refers to the number of warp and weft yarns arranged in one square inch. The size of the density directly affects the physical and mechanical indicators of the fabric's appearance, feel, thickness, strength, folding resistance, air permeability, abrasion resistance and thermal insulation performance, and it is also related to the cost and production efficiency of pvc tarpaulin products.
There are two methods for measuring the warp and weft density of pvc tarpaulin:
1. The direct measurement method is completed by means of a cloth mirror or a fabric density analysis mirror. The length of the scale of the fabric density analysis mirror is 5cm. Under the analysis lens, a long glass piece is engraved with a red line. When analyzing the fabric density, move the lens and align the red line on the glass piece and the red line on the scale at the same time. Between the yarns, take this as the starting point, and count the yarns while moving the lens until the 5cm scale line is this. The number of output yarns is multiplied by 2, which is the density value of 10cm fabric.
When counting the number of yarns, the center between the two yarns should be taken as the starting point. If the count reaches the end, it exceeds 0.5, and if it is less than one, it should be counted as 0.75; if it is less than 0.5, then Calculated by 0.25. Generally, 3-4 data should be measured for pvc tarpaulin density, and then the arithmetic mean value should be taken as the measurement result.
2. The indirect test method is suitable for pvc tarpaulin with high density and small yarn speciality and regular organization. First, after analyzing the fabric structure and the number of weave cyclic warp yarns (the number of weave cyclic weft yarns), and then multiplying the number of weave cycles in 10cm, the product obtained is the warp (weft) yarn density.