Description

Heavy Hex Bolts

SeveralASTM specificationsrequire a hex head that is larger than a standard (finished) hex head. These specifications include: A193, A320and A307B. Although A325 andA490bolts also require a heavy hex head, please refer to Structural Boltsfor dimensional specifications, since these bolts have shorter thread lengths than standard heavy hex bolts.

Manufacturing

Taida Bolt manufactures heavy hex bolts from 1/2" diameter through 2-1/2" diameter in most ASTM, AASHTO, and SAE specifications. Special tooling can be created to produce nonstandard head dimensions or bolt heads with your company's name and/or logo.

Standard: ASTM A325/A563/F436
Dia.: 1/2"-1 1/2";
Length:1 1/4"-8";
Surface treatment: Plain ,Black oxygenation, HDG

Standard Thread Lengths

Bolt lengths < 6": Thread length = (2 X diameter) + 1/4"
Bolt lengths > 6": Thread length = (2 X diameter) + 1/2"

Dimensions

Bolt Diameter	D	F			C		H
	Body Diameter	Width Across Flats			Width Across Corners		Height
	Max	Basic	Max	Min	Max	Min	Basic	Max	Min
1/2	0.515	7/8	0.875	0.850	1.010	0.969	11/32	0.364	0.302
5/8	0.642	1-1/16	1.062	1.031	1.227	1.175	27/64	0.444	0.378
3/4	0.768	1-1/4	1.250	1.212	1.443	1.383	1/2	0.524	0.455
7/8	0.895	1-7/16	1.438	1.394	1.660	1.589	37/64	0.604	0.531
1	1.022	1-5/8	1.625	1.575	1.876	1.796	43/64	0.700	0.591
1-1/8	1.149	1-13/16	1.812	1.756	2.093	2.002	3/4	0.780	0.658
1-1/4	1.277	2	2.00	1.938	2.309	2.209	27/32	0.876	0.749
1-3/8	1.404	2-3/16	2.188	2.119	2.526	2.416	29/32	0.940	0.810
1-1/2	1.531	2-3/8	2.375	2.300	2.742	2.622	1	1.036	0.902
1-3/4	1.785	2-3/4	2.750	2.662	3.175	3.035	1-5/32	1.196	1.054
2	2.039	3-1/8	3.125	3.025	3.608	3.449	1-11/32	1.388	1.175
2-1/4	2.305	3-1/2	3.500	3.388	4.041	3.862	1-1/2	1.548	1.327
2-1/2	2.559	3-7/8	3.875	3.750	4.474	4.275	1-21/32	1.708	1.479

Dimensions per ASME B18.2.1 1996

Scope

The ASTM A325 specification covers high strength heavy hex structural bolts from ½” diameter through 1-1/2” diameter. These bolts are intended for use in structural connections and therefore have shorter thread lengths than standard hex bolts. Refer to the Structural Bolts page of our site for thread lengths and other related dimensions.

This specification is applicable to heavy hex structural bolts only. For bolts of other configurations and thread lengths with similar mechanical properties, see Specification A 449.

Bolts for general applications, including anchor bolts, are covered by Specification A 449. Also refer to Specification A 449 for quenched and tempered steel bolts and studs with diameters greater than 1-1/2" but with similar mechanical properties.

Types

TYPE 1	Medium carbon, carbon boron, or medium carbon alloy steel.
TYPE 2	Withdrawn November 1991.
TYPE 3	Weathering steel.

T	Fully threaded A325. (Restricted to 4 times the diameter in length)
M	Metric A325.

Connection Types

Mechanical Properties

Size	Tensile, ksi	Yield, ksi	Elong. %, min	RA %, min
1/2 - 1	120 min	92 min	14	35
1-1/8 - 1-1/2	105 min	81 min	14	35

Recommended Nuts and Washers

Nuts			Washers
Type 1		Type 3	Type 1	Type 3
Plain	Galvanized	Plain
A563C, C3, D, DH, DH3	A563DH	A563C3, DH3	F436-1	F436-3
Note: Nuts conforming to A194 Grade 2H are a suitable substitute for use with A325 heavy hex structural bolts. The ASTM A563 Nut

Company profile

Ningbo Taida Hezhong Fastener Manufacturing Co., Ltd. is located at No. 286 Galaxy Road, Chengdong Industrial Park, Economic Development Zone, Xiangshan, Ningbo China. The company was founded in 2003 and covers an area of 13999 square meters, including a building area of 11899 square meters. The company has developed to a high professional level in the industry, specializing in the production of high-strength bolts, nuts, bolts, and non-standard special fasteners that are resistant to high pressure, high and low temperature, and corrosion, as well as high-strength bolts, nuts, bolts, and non-standard fasteners with independent research and development patents that never loosen. In recent years, the company has been committed to developing coating technology for various harsh environments and media, producing coating products to meet the anti-corrosion and acid-base requirements of bolt fasteners, making them widely used in petroleum drilling and production equipment, petrochemical equipment, pumps, valves, and seals, petrochemical pipeline containers, and marine engineering. Fasteners for equipment in highly corrosive and harsh environments such as platforms, oil well production, seawater/water injection and sewage pipelines, hydrogen energy electrolyte tanks, offshore wind power, land-based steel tower wind power, and mixed tower wind power.
Production levels include: 6.8, 8.8, 10.9, 12.9, 10.9HV, 10.9HR, 8.8HR, B7, B7M, B16, L7, L7M, L4 3, B 8, B8 M, 660A \ B \ C \ D, N4400, 410, 420, 600, 625, 655, 665, 718, 2205, 2507, F51, F53, C276, 17-4, 825, 925, N08020
Production range: Diameter M12~M100 (1/2 "~4"); Bolt length 25-200mm; The length of the tooth strip is 55-8800mm.

High Quality

The company has advanced production and inspection equipment, participates in the formulation of several international standards, and has abundant technical strength. It has won 5 national invention patents and 15 national utility model patents.

Advanced Equipment

The company has the most advanced automated stereoscopic warehouse storage system and 20tons - level AGV intelligent handling robots for fastener industry in Ningbo area.

Professional Team

The company has its own R & D team and several senior technical and quality management personnel.

Custom Service

Our company has complete production & testing equipment. Can develop and produce products according to the drawings or samples provided by customers

The Fatest Industrial equipments To Achieve Technology Consulti

The main equipment includes: 4 heat treatment Lines such as 80 meter long multi roll furnace, No. 6 mesh belt furnace, induction furnace and other heat treatment equipments; a robot - automatic hot forging bolt production machine; 21 full - automatic thread rolling machines; 3 multi - station cold forging machines; 9 chamfering - stamping machines; 1 dedicated production line for windpower anchor bolts; 3 turning - milling compound machines; 1 model - 100 peeling machine; 1 model - 40 peeling machine; 1 model - 100 straightening and calendering machine. The inspection equipment includes: 200 tons and 100 tons tensile strength testing machines; a fully automatic impact testing machines; an ultrasonic flaw detector; a magnetic particle flaw detectors; an eddy current flaw detector; 3 hardness test machines; a torque testing machine; a transverse vibration testing machine; a German Spectro desktop spectrometer; an American Niton handheld spectrometer; a projector; a metallographic analysis microscope, and other advanced laboratory equipment and dedicated vacuum-tight chamber .

We can provide a variety of fasteners, in line with national standards, the Ministry of Chemical Industry standards, the United States ASTM standards

Complete certificate: API-20E, API-20F, NORSOK M650/ISO17782，TUV Nande CE certification, TUV Nande AD2000 certification,ISO9001, ISO14001, ISO45001, to meet the needs of customers in many fields.

Diameter M12~M100 (1/2 "~4"); Bolt length 25-200mm; The length of the tooth strip is 55-8800mm.

During the development process, the company has always focused on the construction and improvement of the quality management system.

200 ton and 100 ton tensile strength testing

fully automatic impact testing machines

hardness machines

Magnetic particle testing machine permeation chamber

A325/A563/F436 Heavy hex structural bolts

Standard Thread Lengths

Dimensions