TM 55-2200-001-12
Change 3
Section No. 1--General Rules (Rev.-9-1982)
(o)
Turnbuckles
(1)
Turnbuckles must meet Federal Specifications FF-T-791, latest revision and must be open body forged
type.
(2)
Each turnbuckle shall be permanently marked with a working load and the manufacturer's name and
trademark.
(3)
Turnbuckles when used must be locked to prevent loosening by using jam nuts or wiring.
(4)
Turnbuckles used in tie-down systems In conjunction with cables, chains or rods must have a working load
value not less than the component parts of the securement system.
(5)
Turnbuckles using open hooks must have hooks wired unless equipped with a retaining feature.
(6)
The following table shows the breaking strength and working loads of turnbuckles in combination with end
attachments used.
BREAKING STRENGTH AND END PULL OF TURNBUCKLES
Breaking Strength Minimum
Recommended Working Loads
Size, Nominal
Jaw, Eye,
Jaw, Eye,
Outside Diameter
or Stub
Hook End
or Stub
Hook End
of Thread
End Pulls
Pulls
End Pulls
Pulls
Inches
Pounds
Pound.
Pounds
Pounds
3/4
20,000
10,200
4,000
2,000
7/8
29,000
12;Q00
5,800
2,400
1
38,000
14,500
7,600
2,900
1 1/4
60,000
23,000
12,000
4,600
1 3/8
72,000
29,000
14,000
5,800
1 1/2
85,000
36,000
17,000
7,200
D-32.5
