Experimental studies were conducted to confirm the idea that the tensile force is the most important factor influencing the withdrawal saws and determining the stability of the cutting process as a whole
In the course of the experiment were established factors influencing the withdrawal
1) Cutting speed.
2) The distance between the rails.
3) The speed and feeding force to the tooth.
4) Tension band saw blade.
5) Tool wear.
6) The geometry of the tooth.
Until now, it was always assumed that the determinants of withdrawal are primarily divorce saw teeth. Due to the asymmetry of divorce and divorce occurs when such a twisting of individual teeth should consider three factors: the actual value of the divorce of individual teeth, the difference between the value of a divorce right and left, as well as the size and nature of twisting the teeth. All three factors, as previously described, act on withdrawal. It should be borne in mind that the modern methods of manufacture of band saw blades are made relatively equally divorced saws. However, the blade could also be made with a deviation of 1 ° or more, which leads to significant slip problem. Experiments to assess the impact of blade tension were carried out on the machine KSA 8532, while cutting the blank of steel 45 diameter 210 mm. The parameters of the machine were as follows: speed of 60 m / min, a cutting 8 min. Productivity 43 cm2 / min. When used properly bedded saws. The experiment was conducted as follows: after the installation of the work piece and the machine settings were made on 3 cutting tension with a force of 100, 120, 200, 250 and 300 N / mm 2. Next, the experiment was re-organized on the already worn-out saw, but before the onset of catastrophic wear (withdrawal saw more than 1 mm to 100 mm cutting plane). The results of the experiment are shown in Fig. 1 and Fig. 2
Figure 1 - Dependence of withdrawal saw relief. Run-saw.
Figure 2 - Dependence of withdrawal saw relief. Worn saw.
During the research it was established experimentally that the data on the force blade tension recommended by manufacturers in most cases, are too low and need to increase by 10-15% depending on the type and rigidity of the machine. According to the results of the experiment may be recommended following tension force for different classes of machine tools are presented in Table. 1
Table 1 - Recommended values of blade tension.