Nomenclature For Bolts; Bolt Strength Identification - Ford LSG 875 Service Manual

NOMENCLATURE
FOR BOLTS
(ENGLISH) INCH SYSTEM
METRIC SYSTEM
Bolt, 112-l 3x1.25
Bolt Ml 24.75~25
--f-m-
-f--f-T
G DT L
p D T L
1
1
D
D
-.I
-I
D- Nominal Diameter
(inches)
G- Grade Marking
(bolt strength)
L- Length, (inches) **
T- Thread Pitch
(thread/inch)
D- Nominal Diameter
P- Property Class*
(millimeters)
(bolt strength)
L- Length (millimeters)""
T- Thread Pitch (thread width
crest to crest mm)
*The property class is an Arabic numeral distinguishable from the slash SAE English grade system.
""The length of all bolts is measured from the underside of the head to the end.
\ BOLT STRENGTH IDENTIFICATION
(ENGLISH) INCH SYSTEM
Grade 1 or 2
Grade 5 Grade 8
(English) Inch bolts - Identification marks correspond to bolt strength - increasing number of slashes represent increasing
.
strength.
METRIC SYSTEM
Metric bolts - Identification class numbers correspond to bolt strength - increasing numbers represent increasing strength.
Common metric fastener bolt strength properties are 9.8 and 10.9 with the class identification embossed on the bolt head.
.-
5