ASME B18.2.2Hexagon

ASME B18.2.2 3/4-10 Hexagon

ASME B18.2.2 3/4-10 is a hex nut, on a 3/4-10 UNC thread at 10 tpi. The inch-series finished hex nut in UNC. Height and width across flats are held to inch dimensions, so it will not match a metric wrench even where the thread diameter is close.

Dimensioned drawing — ASME B18.2.2 3/4-10s 1.13
ASME B18.2.2 3/4-10 — HexagonNominal dimensions in inches · Not to scale
Nominal Ø0.75 in
Socket size s1.125 in
Head Ø dk1.299 in
Height m0.6406 in
HeadHexagon

Dimensions

Standard
ASME B18.2.2
Type
Hex nut
Size
3/4-10
Socket size s
1.125 in
Head diameter dk
1.299 in
Height m
0.6406 in
Head
Hexagon

Nominal values in inches as published in ASME B18.2.2. Estimated weight 31.334 g per piece in steel (31.533 g in stainless), calculated from the nominal geometry — real parts vary with tolerance and head chamfers.

Designation3/4-10 UNC
Threads per inch10 tpi
Nominal Ø0.75 in
Pitch Ø0.6850 in
Minor Ø ext0.6272 in
Tap drillØ 0.6500 in

Other lengthsASME B18.2.2 3/4-10

All 3/4-10 specifications

Choosing and fitting this size

ASME B18.2.2 3/4-10 is a 3/4-10 nut, on a 10 tpi UNC thread. Mating threads should be a matching class nut in the same property class.

Inch fasteners are graded under SAE J429, not ISO 898-1. Grade 2 is unmarked low carbon, Grade 5 carries three radial lines on the head and Grade 8 carries six. Grade 8 reaches roughly 1034 MPa tensile — close to metric class 10.9 — but the grades and thread forms are separate systems and the two should not be mixed in one joint. Never put a Grade 5 nut on a Grade 8 bolt: the thread strips first and the failure moves into the nut.

For a tapped hole, 3/4-10 takes a 0.6500 in tap drill, and the external thread's minor diameter is 0.6272 in — that is the section carrying the load, not the nominal 3/4-10 figure. Inch tap drills come from the thread tables rather than the metric rule of thumb (major diameter minus pitch), because TPI does not map onto that formula. Engagement of at least one times the nominal diameter is what lets the bolt fail before the thread strips.