ASTM F3043 tension Control Bolt Specification

Quenched & Tempered Alloy Steel Twist Off Type Tension Control Bolts Nuts & Washers

ASTM F3043 Tension Control TC Bolts

ASTM F3043 pecification covers one style of heat treated, alloy steel, tension control bolt-nut-washer assemblies, also referred to as "sets," having a tensile strength of 200 to 215 ksi. These assemblies are capable of developing a minimum predetermined tension when installed by applying torque to the nut, while at the same time applying a counter torque to separate the spline end from the body of the bolt using an appropriate spline drive installation tool. An assembly consists of a tension control bolt with spline end, nut and washer covered by this specification. The assemblies are available with round heads in sizes 1 inch to 1 1/4 inch inclusive. The fastener assemblies are intended for use in structural connections in the following environmental conditions:
Interiors, normally dry, including interiors where structural steel is embedded in concrete, encased in masonry or protected by membrane or noncorrosive contact type fireproofing.
Interiors and exteriors, normally dry, under roof, where the installed assemblies are soundly protected by a shop-applied or field-applied coating to the structural steel system.

ASTM F3043 Chemical Requirements

ASTM F3043 Chemical Requirements for Tension Control Bolts^A

Element	Heat Analysis, %		Product Analysis, %
	min	max	min	max
	C	0.38	0.42	0.36	0.44
Mn	0.40	0.60	0.37	0.63
P	. . .	0.01	. . .	0.015
S	. . .	0.01	. . .	0.015
Si	. . .	0.10	. . .	0.12
Cr	1.20	1.40	1.15	1.45
Mo	0.60	0.80	0.57	0.83
V	0.30	0.40	0.27	0.43
(A) Aluminum, cobalt, niobium / columbium, nickel, titanium, tungsten, zirconium, or any other alloying elements may be added to obtain the desired alloying effect.

ASTM F3043 Chemical Requirements for Nuts

Element	Heat Analysis, %		Product Analysis, %
	min	max	min	max
	C	0.30	0.48	0.28	0.50
Mn	0.60	0.90	0.57	0.93
Si	0.15	0.35	0.13	0.37
P	. . .	0.050	. . .	0.055
S	. . .	0.050	. . .	0.055

ASTM F3043 Chemical Requirements for Washers

Element	Heat Analysis, %		Product Analysis, %
	min	max	min	max
	C	0.42	0.48	0.40	0.50
Mn	0.60	0.90	0.57	0.93
Si	0.15	0.35	0.13	0.37
P	. . .	0.030	. . .	0.035
S	. . .	0.030	. . .	0.035

ASTM F3043 Mechanical Requirements

ASTM F3043 Hardness Requirements for Tension Control Bolts

Bolt Size, in.	Bolt Length, in.	Rockwell C
		min	max
1 to 11/4 , incl	all	38	45

ASTM F3043 Tensile Requirements for Full Size Tension Control Bolts

Grade	Bolt Size, Threads per in.	Stress Area, in.2 A,B	Tensile Load, lbfC
			min	max
ASTM A3043 Grade 1	1 in. - 8	0.615	123 100	132 300
	11/8 in. - 7	0.776	155 200	166 800
	11/4 in. - 7	0.983	196 700	211 400
ASTM A3043 Grade 2	1 in. - 8	0.640	128 000	137 700
	11/8 in. - 7	0.808	161 600	173 600
	11/4 in. - 7	1.019	203 800	219 100
(A) The stress area for Grade 1 is calculated as: As = 0.7854 [0.5 (d3 max + d2 max)]2 (B) The stress area for Grade 2 is calculated in accordance with Annex A1. (C) Loads tabulated are based on the following: Bolt Size, in. = 1 to 11/4 Tensile Load min = 200 000 psi Tensile Load min = 215 000 psi

ASTM F3043 Tensile Strength Requirements for Specimens Machined from Bolts

Nominal Bolt Diameter, in.	Tensile Strength, ksi		Yield Strength (0.2 % offset), min, ksi	Elongation in 2 in. or 50 mm, min, %	Reduction of Area, min, %
	min	max
1 to 11/4 , incl	200	215	180	14	40

ASTM F3043 Hardness Requirements for Nuts

Bolt Size, in.	Surface Hardness, Rockwell C
	min	max
1 to 11/4 , incl	30	40

ASTM F3043 Proof Load Requirements for Nuts

Grade	Nominal Size - Threads per in.	Stress Area, As, in.2 A,B	Proof Load Stress, ksi	Nut Proof Load, lbfC
ASTM A3043 Grade 1	1 in. - 8	0.615	200	123 100
	11/8 in. - 7	0.776	200	155 200
	11/4 in. - 7	0.983	200	196 700
ASTM A3043 Grade 2	1 in. - 8	0.640	200	128 000
	11/8 in. - 7	0.808	200	161 600
	11/4 in. - 7	1.019	200	203 800
(A) The stress area for Grade 1 is calculated as: As = 0.7854 [0.5 (d3 max + d2 max)]2 (B) The stress area for Grade 2 is calculated in accordance with Annex A1. (C) To determine nut proof load in pounds, multiply the appropriate nut proof load stress by the tensile stress area of the thread.

ASTM F3043 Core Hardness Requirements for Washers

Rockwell C
Min 40	Max 45

ASTM F3043 Assembly Lot Tension Test Requirements

Bolt Size, in.	Grade 1		Grade 2
	Manufacturers Acceptance Test Tension, lbs, minA	Tension lbs, min (for information only)B	Manufacturers Acceptance Test Tension, lbs, minA	Tension lbs, min (for information only)B
	1	90 000	86 000	94 000	90 000
11/8	114 000	109 000	119 000	113 000
11/4	145 000	138 000	150 000	143 000
(A) The manufacturer's acceptance test tension values are 5 % higher than the tension in Column 2 and are rounded to the nearest 1000 lbs (kip). (B) The values in Column 2 are equal to 70 % of the specified minimum tensile strength for tests of full size F3043 bolts tested in axial tension and are rounded to the nearest 1000 lbs (kip).

ASTM F3043 Tension Control Bolt Dimensions

Parameters	Range	Size
Nominal Size	...	1	11/8	11/4
Basic Diameter, E, in.A	...	1.000	1.125	1.250
Full-Size Body Diameter E, in.	max	1.022	1.149	1.277
	min	0.976	1.098	1.223
Head Height, H, in.B	nom	39/64	11/16	25/32
	max	0.643	0.738	0.824
	min	0.607	0.678	0.759
Head Diameter, D, in.C	nom	21/8	23/8	21/2
	max	2.158	2.375	2.589
Bearing Diameter, C, in.D	nom	2	21/4	21/2
	min	1.771	1.991	2.224
Radius of Fillet, R, in.	nom	3/32	3/32	7/64
	max	0.110	0.110	0.138
	min	0.087	0.087	0.098
Transition Body Diameter, ER, in.	nom	59/64	11/32	15/32
	max	0.933	1.046	1.171
	min	0.917	1.030	1.155
Body Transition Length, Y2, in.	nom	0.305	0.354	0.354
	max	0.394	0.450	0.450
	min	0.207	0.244	0.244
Reduced Body Length, LR, in.	nom	1/2	9/16	9/16
	max	0.625	0.715	0.715
	min	0.375	0.429	0.429
Transition Thread Length Y1, in.E	Ref	0.31	0.34	0.34
Thread Length, LT, in.F	Ref	2.049	2.322	2.322
Maximum center of groove to First Fully Formed Thread, U, in.G	Max	0.455	0.500	0.500
Spline Length, Ls, in.H	Ref	0.80	0.90	0.984
Spline Width Across Flats, S, in.H	Ref	0.700	0.787	0.897
(A) Where specifying nominal size in decimals, zeros preceding the decimal shall be used and the fourth decimal place shall be omitted. (B) The head height shall be that overall distance measured parallel to the axis of the product from the top of the head to the bearing surface and shall include the thickness of the washer face. Raised grade and manufacturer's identification are excluded from head height. (C) The circumference may be irregular with a rounded or flat edge. (D) The bearing surface shall be flat and perpendicular to the body within the FIM limits specified for total runout. Measurement of FIM shall extend as close to the periphery of the bearing surface as possible while the bolt is being held in a collet or other gripping device at a distance of one bolt diameter from the underside of the head. A die seam across the bearing surface is not permissible. (E) Transition thread length, Y1, is a reference dimension, intended for calculation purposes only, that represents the length of incomplete threads and tolerance on grip gaging length. (F) See ASME B18.2.6, section. (G) Unless otherwise specified, bolts need not be pointed. The distance, U, is from the center of the groove to the first fully formed thread crest. This shall be determined by measuring how far the point enters into a cylindrical NOT GO major diameter ring gage. (H) The spline dimensions and groove dimensions are reference dimensions and shall be at the discretion of the manufacturer. Users should consult with the supplier to assure wrenchability.

ASTM F3043 Nut Dimensions

Parameters	Range	Size
Nominal SizeA	. . .	1	11/8	11/4
	. . .	1.000	1.125	1.250
Width Across Flats, FB	nom	15/8	113/16	2
	max	1.625	1.812	2.000
	min	1.575	1.756	1.938
Width Across Corners, GC	max	1.876	2.093	2.309
	min	1.796	2.002	2.209
Thickness, HD	nom	13/16	111/32	115/32
	max	1.214	1.367	1.501
	min	1.147	1.295	1.424
Washer Face Height	nom	1/64	1/64	1/64
	Total Runout of Bearing Face FIME	0.024	0.027	0.030
(A) Where specifying nominal size in decimals, zeros preceding the decimal shall be used and the fourth decimal place shall be omitted. (B) The width across flats of heavy hex nuts shall be the overall distance measured, perpendicular to the axis of the nut, between two opposite sides of the nut. No transverse section through the nut between 25% and 75% of the actual nut thickness, as measured from the bearing surface, shall be less than the minimum width across flats. (C) A rounding or lack of fill at junction of hex comers with chamfer shall be permissible, provided the width across comers is within specified limits at and beyond a distance equal to 17.5% of the basic thread diameter from the chamfered faces. (D) The nut thickness shall be the overall distance measured parallel to the axis of the nut, from the top of the nut to the bearing surface, and shall include the thickness of the washer face where provided. (E) Nuts shall have a washer faced bearing surface and chamfered top. The diameter of washer face shall be within the limits of the maximum width across flats and 95% of the minimum width across flats.

ASTM F3043 Hardened Circular Washers Dimensions

Parameters	Range	Size
Nominal Size	. . .	1	11/8	11/4
Inside Diameter (ID), in.	nom	11/16	13/16	13/8
	max	1.085	1.251	1.438
	min	1.063	1.188	1.375
Outside Diameter (OD), in.	nom	2	21/4	21/2
	max	2.063	2.313	2.563
	min	1.937	2.187	2.437
Thickness (T), in.	nom	1/4	1/4	5/16
	max	0.264	0.264	0.343
	min	0.209	0.209	0.287

ASTM F3043 Basic Thread Dimensions, Grade 2 Assemblies

Parameters	Size
Nominal Size, in.	1	11/8	11/4
Major Diameter, in.	0.9980	1.1228	1.2478
Threads per inch	8	7	7
Pitch, in.	0.1250	0.1429	0.1429
A, in.	0.0135	0.0155	0.0155
B, in.	0.0460	0.0526	0.0526
C, in.	0.0106	0.0121	0.0121
D, in.	0.0381	0.0435	0.0435
E, in.	0.0167	0.0190	0.0190
F, in.	0.0281	0.0321	0.0321
G, in.	0.0180	0.0206	0.0206
H, in.	0.1083	0.1237	0.1237
J, in.	0.0722	0.0825	0.0825
M, in.	0.0054	0.0062	0.0062
Q, in.	0.1104	0.1261	0.1261
As = (π /4)[(d2 + d3)/2]2 where: As = tensile stress area, in.2 dbsc = basic major diameter, in. n = threads per in. H = (√3 / 2) * dbsc/n d2 = dbsc - (3/4 H) d1 = d2 - 2(H / 20) θ = sin-1 (2√3 / 15) z = (H / 6) (cos θ) x′ = (H / 6) (sin 30°) y = (H / 2) (cos θ) z′ = (2H / 3) - y - z d3 = d1 - 2 (z - x′ + z′)

ASTM F3043 Pre-Installation Verification Testing, Pretensioning And Inspection

Bolt Size, in.	Pretension, pounds, min
	Grade 1	Grade 2
1	90 000	94 000
11/8	114 000	119 000
11/4	145 000	150 000

ASTM F3043 Bolting Surface Treatment Specifications

ASTM F3043 Bolting Components Marking

Product Shall be Marked with our manufacturing trade mark "TorqBolt" or "TB" along with the designated Grade.
Grade and manufacturer’s identification symbols shall be applied to one end of studs and to the heads of bolts and screws of all sizes. (If the available area is inadequate, the grade symbol may be marked on one end and the manufacturer’s identification symbol marked on the other end.) For bolts and screws smaller than 1⁄4 in. [6 mm] in diameter and studs smaller than 3⁄8 in. [10 mm] in diameter and for 1⁄4 in. [6 mm] in diameter studs requiring more than a total of three symbols, the marking shall be a matter of agreement between the purchaser and the manufacturer.