Contact Stresses

Contact Stresses

 

stresses arising from the mechanical interaction of solid deformable bodies in their areas of contact and in the vicinity of such areas—for example, during compression of bodies that are touching. A knowledge of contact stresses is important in calculating the strength of bearings, gear and worm drives, ball and cylindrical rollers, and cam mechanisms.

Contact stresses decrease rapidly with increasing distance from the area of contact. The distribution of contact stresses over the area of contact (see Figure 1) and in its vicinity is nonuniform and is characterized by large gradients. The maximum tangential stresses max, which to a large extent determine the strength of compressed bodies (for example, in the compression of spheres or intersecting cylinders), arise at a certain depth (point A) beneath the area of contact. The stress state in the immediate vicinity of this area is close to hydrostatic compression, for which tangential stresses are known to be absent.

Figure 1. Stress distribution upon compression of spherical bodies: ( P ) compressive force, ( R1 ,) and (R2) radii of the spheres, ( p0 ) maximum stress in the center of the area of contact S, (p) stress at distance r from the center of the area of contact, (a) radius of area of contact, (A) point of maximum stress

References in periodicals archive ?
evaluation of the selected sf technologies for application on typical mechanism contacts considering:surface (bearings gears plain bushes) materials (bearing steels gear steels hardening methods) lubricants (mos2 pfpe lubricants mac lubricants) environment (air vacuum n2 operational and launch loads preload in bearings operational contact stresses stresses due to thermal cycling and differential thermal expansion)3.
This interface enhances strength of GEMS software in inspecting and analyzing micro-geometry of gear tooth, transmission errors and contact stresses. Mahr extended its gear measuring machines product line by introducing a range of new confocal measuring systems particularly for 3D measurements that facilitate efficient gear surface inspection.
We note that the trailer wheels exerted maximum contact stresses as high as ~340 kPa.
Effect of wood species and glue type on contact stresses in a mortise and tenon joint, Journal of Mechanical Engineering Science, 222(12) 2008, pp.
In this case, the contact stresses arise as a local stress concentration that can be assumed independent of stresses in the bulk of the bodies.
In this scientific perspective, this paper analyzes different design factors affecting contact stresses at the TMJ prosthesis interface (i.e., the contact interface between the mandibular and the glenoid fossa components), which are consequently involved in their deterioration and final failure.
These six stresses are collectively referred to as the control stress of the BDP, while [[tau].sub.xy], [[tau].sub.yz], and [[sigma].sub.y] are interlayer contact stresses.
It was particularly interesting to see a decrease in the values of femoral and tibial contact stresses and the load percentage from 3?[degrees] valgus to 3?[degrees] varus lower limb alignment [Table 2].
The gear contact stresses derived from tooth contact forces and geometry are very important for determining gear pitting, i.e.
Combating the die wear is one of the crucial challenges in sheet metal forming industry due to increased level of contact stresses at the forming die/sheet blank interface in addition to the elevated springback issues in stamped parts.
Moreover, it has been reported that mobile bearing insert significantly improved patellar tracking with decreased patellofemoral contact stresses than fixed bearing insert in an intraoperative kinematic study [6].
According to AGMA standard, the tangential component is the source of bending and contact stresses acting on gear tooth and these stresses are used to establish design or check safety for realistic design.