Air-gap adjustment. Wear 0,1 mm
The maximum number of operations mmax that you can do before the adjustment of brake, may be obtained by the graph n° 2.
Enter onto the x-axis with the work to dissipate (L) and read on the intersection between the curve of the selected brake and the y-axis, the total number of operations. The time (h) for the air-gap adjustment is calculated with the following formula:
The preivous formula allows the calculation of a wear equal to 0,1 mm. The functionality of the brake is guaranteed for a max value of the air-gap of 0,7 mm (wear 0,5 mm).
Rough calculation of the braking torque
If you just know the motor power (W) and its greatest number of revolutions per minute (no), it’s possible select the necessary braking torque (Mf) with a rough calculation, using the following formula:
If it isn’t possible to check the heat dissipation, the safety coefficient CS must be selected according to the specific requested application.
Determine the load acting on the system in order to select the load application. From paragraph "Selection criteria” select the kind of load acting on the system. The four events indicated satisfy most of the frequent braking events. Choose then the formula according to the loading torque. In formula 1, ML takes energy from the loading torque, so the value Mf can be lower than ML.
Numerical example of calculation
In formula 2, ML adds energy to the loading torque, so the value Mf can be higher than ML. Calculate with formula 3 the necessary braking torque. Select in the catalogue the brake with an higher braking torque.
Determine the heat dissipation using the formulae in paragraph "Check of heat dissipation”. With the Joule value enter onto graphic 1 and check if the heat dissipation of the brake is compatible with the number of operations to carry out. With graphic 2 determine the number of operations for the air-gap adjustment.
The load belongs to class C.
From the formula 1
To formula 3
Select in our catalogue the brake model K05 with a braking torque of 35Nm.
Check then the heat dissipation of the selected brake. Calculate the work to dissipate (J) with formula 6
(as the load belongs to class C).
Check into graphic 1 if the selected brake model K05 can bear the caculated work (J) according to the number of operations to carry out. The brake can bear a work of about 28000 J, so the brake selected is correct. With the graphic 2 you can gather the number of operations to carry out before adjusting the air-gap (wear 0,1 mm).
The value obtained is 15000 which divided by the number of operations /hour to carry out, gives a value of 500 working hours. Knowing that the air-gap can reach a maximum value of 0,5 mm, you must adjust it within 2500 working hours.
