Page 4 - Goodyear2011PTMaintenanceManual

4
V-Belt
INSTALLATION GUIDE
Industry Standard Groove Dimensions
for V-Belt Sheaves
Check sheaves for cleanliness, damage and wear each time belt
maintenance is performed and whenever belts are changed. The
inspection procedure is described on page 6 of this guide.
Use the tables (Tables 1 and 2) and tolerance data below
as a reference to determine i f excessive sheave wear has
occurred. They can also aid in replacement belt cross-section
selection, if necessary.
The tables are based on industry standard dimensions for V-belt
sheaves. Always check the original sheave specifications if
possible. Variances from industry standards can occur to provide
for special design or performance requirements.
(1) Diameters shown for combination grooves are outside diameters.
A specifc datum diameter does not exist for either A or B belts in
combination grooves.
(2) The “a” values shown for the A/B combination sheaves are the
geometrically derived values. These values may be different than
those shown in manufacturer’s catalogs.
Summation of the deviations from “Sg” for all grooves in any one
sheave shall not exceed ±0.050 inches.
The variation in datum diameter between the grooves in any one
sheave must be within the following limits:
Up through 19.9 inches outside diameter and up through 6 grooves:
0.010 inches (add 0.0005 inches for each additional groove.)
20.0 inches and over on outside diameter and up through 10
grooves: 0.015 inches (add 0.0005 inches for each additional groove.)
This variation can be obtained easily by measuring the distance across
two measuring balls or rods placed diametrically opposite each other
in a groove. Comparing this “diameter over balls or rods” measurement
between grooves will give the variation in datum diameter.
Deep groove sheaves are intended for drives with belt offset such as
quarter-turn or vertical shaft drives. (See RMA Power Transmission Belt
Technical Information Bulletin IP-3-10, V-belt drives with twist).
Joined belts will not operate in deep groove sheaves.
Also, A and AX joined belts will not operate in A/AX and B/BX combination grooves.
OTHER SHEAVE TOLERANCES
Outside Diameter
Up through 8.0 inches
outside diameter.....±0.020 inches
For each additional inch of outside
diameter add.....±0.005 inches
Radial Runout**
Up through 10.0 inches
outside diameter.....±0.010 inches
For each additional inch of outside
diameter add.....±0.0005 inches
Axial Runout**
Up through 5.0 inches
outside diameter.....±0.005 inches
For each additional inch of outside
diameter add.....±0.001 inches
**Total Indicator Reading
TABLE 1 GROOVE DIMENSIONS —INCHES
Face Width of Standard
and Deep Groove Sheaves
Face Width = Sg (Ng –1) + 2Se
Where:
Ng =Number of Grooves