Grain Systems Tanks PNEG-4075A - Manual (Page 105)

Chapter 7: Roof Assembly
• Before attempting a lift, adjust each lifting cable to achieve the appropriate angle needed (approxi-
mately 30 degrees).
• Assemble the A-frames with X-bracing last, so that they can be easily accessed to be lifted into place
first.
Table 7-3 For alpha roof
Bin Diameter Peak Capacity Roof Snow Load Approximate A-Frame Weight
75 ft. (22.86 m) 50 K 30 PSF 770 lb (349 kg)
75 ft. (22.86 m) 50 K 30 PSF 1176 lb (533 kg)
(three rafter assembly)
The part variance multiplier is 4%.
Attaching the A-Frames to the Center Collar
The A-frame rafters must be installed to support the center collar and main roof structure.
Before You Begin
The center collar should be assembled and secured to the support pole, and the A-frame rafters should be
assembled. Determine the correct location of each A-frame. For more information, see
Center Collar
Placement , page 100 . Read and understand the safe and proper lifting procedures needed to install the
A-frames. For more information, see Guidelines for Assembling and Lifting the A-Frame Rafter Sections,
page 103 .
1. Carefully lift the A-frame assembly (A) into position, and align with the proper holes on the center
collar (B).
2. Install flange bolts (C) and flange nuts (D) as shown.
3. Before continuing with the remaining A-frame rafters, secure the A-frame rafter to the eave clip. See
Attaching the A-Frame to the Eave Bracket , page 106 .
Pneg-4075A 75 Ft Diameter 40-Series Bin 105