ROLLIX slewing rings generally incorporate a SLEWING mechanism
to control rotation of the mobile part. This function can be achieved by various means :
1. gear drive (the most frequent case)
2. belt drive
3. chain drive
4. direct drive
GEAR DRIVE
Involute teeth, spur or helic are directly cut into the outer or
inner ring (spur gear only). Cf Profile Addedum Modifications
GEOMETRY
Most of the ROLLIX bearings have a gear improved by
positive addendum modification which notably decreases
pressures as well as by a truncation avoiding teeth root interference at the pinion.
It is also essential to make a positive addendum codification on the pinion teeth, in order to avoid the geometric interference which appears under 18 teeth.
Furthermore, the drive stresses induce shaft bending and gear deformation which are harmful to good meshing. To prevent these faults, we recommend profile corrections are carried out on the pinions : i.e. crowning and tip relief. Our Engineering Department will assist upon request.
RESISTANCE
Our rating graphs indicate the values of allowable maximum tangential force in fatigue T .
The continuous operating capacity is obtained by the application of a suitable load moderating factor.
T=2 C D /D ref
C D = Torque on gear
D ref = Reference diameter
Unless otherwise stated, the indicated values are valid for geared rings made of normalized steel XC45: code Z.
When these values are not sufficient, ROLLIX can proceed with contour hardening which considerably improves the resistance to tooth root bending and the resistance to contact pressure. For very heavy loading conditions, ROLLIX carries out complete hardening of the tooth and of its root in the wheel rim. When only a better wear resistance is required, surface hardening of tooth flanks only is possible.
Profile Addendum Modifications
GEAR QUALITY
Unless stated otherwise, ROLLIX manufactures slewing ring gears according to AFNOR or DIN standards which meet the following criteria.
WITHOUT SUPERFICIAL HEAT TREATMENT
|
DIN
Class |
AFNOR
Class |
Maximum
diameter |
Maximum
module |
Options |
|
12 |
12 |
all sizes |
25 |
Module 45 with special tooling |
|
10-11-12 |
11-10-9 |
all sizes |
20 |
Specific equipment necessary
. made upon request |
|
9-10 |
8-9 |
3100 |
22 |
|
|
7-8 |
7 |
2500 |
20 |
|
When a higher gear quality such as grade 5 or 6 is needed,
gear grinding becomes necessary (ask our Engineering department)
SUPERFICIALLY HARDENED GEAR
. Generally, by contour hardening to 55 HRc (+- 5)
. The gear classes stated aboce are offset and ROLLIX can meet AFNOR or DIN standards for grades 11-12.
|
IMPORTANT
ROLLIX considers that the relevant gear characterizing parameters for each quality class defined by AFNOR, DIN or ISO must be met.
In case a customer does not require all of the parameters and needs to meet only one or two of them, ROLLIX can achieve higher qualities |
