Roof truss details, Chapter 15 roof truss details – Grain Systems Tanks PNEG-4042 User Manual
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PNEG-4042 40 Series 42' and 48' Diameter Bins
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15. Roof Truss Details
Temperature Cable Support (CRP-5286) (42' and 48' (12.80 m and
14.63 m) Support System)
1. All packages (42' and 48' (12.80 m and 14.63 m)) shall span three (3) roof panel as shown in
.
2. One package should be provided for each cable in the tank with the exception of the center cable.
3. The 42' and 48' package includes bracing angle for the roof rafters, hanging angle and a cable
support channel.
4. Each set of rafters should carry only one temperature cable.
5. Once the roof system has been installed, installation of the cable support packages may proceed as
follows.
6. For 42'-48' bins, center the support angle and drill the holes to bolt the support angle (CRP-5185
(42' and 48') (12.80 m and 14.63 m)) into the roof rafter (
(42' and 48')
(12.80 m and 14.63 m) to locate which holes to drill.) and attach with 3/8" diameter bolts. Support
angles may be installed on the outer surface as indicated in
.
7. Should the angle location be such that the rafter splices coincide with angle placement, the angle
(CRP-5185) should be slid one way enough to align the angle holes with the splice bolts or miss the
splice bolts.
8. Slight adjustments of the radius may be necessary to ensure that the channel support angle holes
and cable support channel holes will correspond. Field drill the holes in the roof rafter for the hanging
of the channel, as illustrated in
.
9. Once the rafters are in place, field drill the holes to bolt the support angle (CRP-5786 or CRP-5787)
into the roof rafter and fasten with 3/8" bolt.
10. Attach the cable attachment bracket (CRP-5213) in the center of the support channel (CRP-5285) as
illustrated in
and hang the cable.
11. If it is desired to support the cable from the flange of the support channel (CRP-5285), it will be
necessary to reinforce the flange with a 12" section of 3" x 3" x 3/16" angle.
12. No more than one cable should be supported from a pair of roof rafters.
13. This package will allow a maximum radius of: (42' equals 16.86') (12.80 m equals 5.14 m), (48' equals
19.22') (14.63 m equals 5.86 m). These radii represent the maximum radius that the cross members
will span. These are not recommended installation locations. Install according to the temperature
cable manufacturer’s recommendations. For a greater radius, the recommendation shown in this
manual for temperature cable installation must be used (using field cut, hot rolled sections), however
a rafter support package must be used.