Heavy Hex ASTM A325 HDG YZP BLACK ZP 800mm Steel Hex Bolt

Place of Origin CHINA
Brand Name QBH
Certification ISO9001
Model Number ASTM A325 1/2 to 1-1/2
Minimum Order Quantity 900kg
Price Negotiation
Packaging Details 25kg Carton+900kg/Pallet
Delivery Time 30days
Payment Terms L/C, T/T,OA
Supply Ability 500TON/MONTH
Product Details
Material Carbon Steel Size 1/2 To 1-1/2
Surface Treatment Plain,Zinc,Black,H.D.G Grade A325
Process Cold Forging,Hot Forging Sample Free Sample
Packaging 25kg Carton+900kg/Pallet Head Type Hex Head
Application Industry,BUILDING Length 10mm-800mm
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A325 Steel Hex Bolt


800mm Steel Hex Bolt


ASTM A325 Stainless Steel Bolts

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Product Description

This specification covers two types of quenched and tempered, steel, metric heavy hex structural bolts having a minimum tensile strength of 830 MPa (Note 1).


Formerly under the jurisdiction of Committee F16 on Fasteners, this specification was withdrawn in May 2016 and replaced by Specification F3125/F3125M for High Strength Structural Bolts, Steel and Alloy Steel, Heat Treated, 120 ksi (830 MPa) and 150 ksi (1040 MPa) Minimum Tensile Strength, Inch and Metric Dimensions. Specification F3125/F3125M supersedes and replaces specifications; A325, A325M, A490, A490M, F1852 and F2280. The unified Specification F3125/F3125M corrects known inconsistencies in the original documents and the combination will assure that requirements of the products covered under the original standards stay aligned.


ASTM Standards

A153/A153M Specification for Zinc Coating (Hot-Dip) on Iron and Steel Hardware

A563M Specification for Carbon and Alloy Steel Nuts (Metric)

A751 Test Methods, Practices, and Terminology for Chemical Analysis of Steel Products

B695 Specification for Coatings of Zinc Mechanically Deposited on Iron and Steel

D3951 Practice for Commercial Packaging

F436M Specification for Hardened Steel Washers (Metric)

F606M Test Methods for Determining the Mechanical Properties of Externally and Internally Threaded Fasteners, Washers, and Rivets (Metric)

F788/F788M Specification for Surface Discontinuities of Bolts, Screws, and Studs, Inch and Metric Series

F959M Specification for Compressible-Washer-Type Direct Tension Indicators for Use With Structural Fasteners (Metric)

F1136M Specification for Zinc/Aluminum Corrosion Protective Coatings for Fasteners (Metric)

F1470 Practice for Fastener Sampling for Specified Mechanical Properties and Performance Inspection

F1789 Terminology for F16 Mechanical Fasteners

G101 Guide for Estimating the Atmospheric Corrosion Resistance of Low-Alloy Steels

ASME Standards

B 1.13M Metric Screw Threads

B 18.18.3M Inspection and Quality Assurance for Special Purpose Fasteners

B Metric Heavy Hex Structural Bolts

B 18.24 Part Identifying Number (PIN) Code System Standard for B18 Fastener Products





Heavy Hex ASTM A325 HDG YZP BLACK ZP 800mm Steel Hex Bolt 0

Screw Thread
1/2 5/8 3/4 7/8 1 1-1/8 1-1/4 1-3/8 1-1/2
ds max
s Nominal Size
e max
k Nominal Size
b Ref.
0.515 0.642 0.768 0.895 1.022 1.149 1.277 1.404 1.531
0.482 0.605 0.729 0.852 0.976 1.098 1.223 1.345 1.47
7/8 1-1/16 1-1/4 1-7/16 1-5/8 1-13/16 2 2-3/16 2-3/8
0.875 1.062 1.25 1.438 1.625 1.812 2 2.188 2.375
0.85 1.031 1.212 1.394 1.575 1.756 1.938 2.119 2.3
1.01 1.227 1.443 1.66 1.876 2.093 2.309 2.526 2.742
0.969 1.175 1.383 1.589 1.796 2.002 2.209 2.416 2.622
5/16 25/64 15/32 35/64 39/64 11/16 25/32 27/32 15/16
0.323 0.403 0.483 0.563 0.627 0.718 0.813 0.878 0.974
0.302 0.378 0.455 0.531 0.591 0.658 0.749 0.81 0.902
1 1.25 1.38 1.5 1.75 2 2 2.25 2.25




Note: In 2016, ASTM A325 was officially withdrawn and replaced by ASTM F3125, in which A325 now becomes a grade under the F3125 specification. The F3125 specification is a consolidation and replacement of six ASTM standards, including; A325, A325M, A490, A490M, F1852, and F2280. We are choosing to keep this technical information about the now obsolete A325 specification on our website for reference and informational purposes only.




Prior to its withdrawl in 2016, the ASTM A325 specification covered high strength heavy hex structural bolts from 1/2″ 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 A449.

Bolts for general applications, including anchor bolts, are covered by Specification A449. Also refer to Specification A449 for quenched and tempered steel bolts and studs with diameters greater than 1-1/2″ but with similar mechanical properties.

A325 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.

A325 Connection Types

SC Slip critical connection.
N Bearing type connection with threads included in the shear plane.
X Bearing-type connection with threads excluded from the shear plane.

A325 Mechanical Properties

Size Tensile, ksi Yield, ksi Elong. %, min RA %, min
12 - 1 120 min 92 min 14 35
118 - 112 105 min 81 min 14 35

A325 Type 1 Chemical Properties

Heat Analysis 120ksi, % 150ksi, %
Carbon 0.30 – 0.52 0.30 – 0.48*
Manganese 0.60 min 0.60 min
Phosphorus 0.035 max 0.035 max
Sulfur 0.040 max 0.040 max
Silicon 0.15 – 0.30 -
Boron 0.003 max 0.003 max
Copper - -
Nickel - -
Chromium - -
Molybdenum - -
*Carbon 0.35-0.53% for 1-1/2” A490/150ksi bolts

A325 Type 3 Chemical Properties

Heat Analysis 120ksi, % Comp A 120ksi, % Comp B 120ksi, % Index 150ksi, % Index
Carbon 0.33 – 0.40 0.38 – 0.48 0.30 – 0.52 0.30 – 0.53
Manganese 0.90 – 1.20 0.70 – 0.90 0.60 min 0.60 min
Phosphorus 0.035 max 0.035 max 0.035 max 0.035 max
Sulfur 0.040 max 0.040 max 0.040 max 0.040 max
Silicon 0.15 – 0.30 0.30 – 0.50    
Copper 0.25 – 0.45 0.20 – 0.40 0.20 – 0.60 0.20 – 0.60
Nickel 0.25 – 0.45 0.50 – 0.80 0.20 min* 0.20 min*
Chromium 0.45 – 0.65 0.50 – 0.80 0.20 min 0.20 min
Molybdenum   0.06 max 0.10 min* 0.10 min*
*Either Nickel or Molybdenum must be present in the amount specified *Corrosion Index based on ASTM Guide G101

A325 Recommended Hardware

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 Compatibility Chart has a complete list of specifications.




Process flow


Cold forging

Annealing treatment(if need) ➨ wiredrawing ➨ clod forging ➨ thread rolling ➨make heat treatmentFinish Packing


Hot forging

Cutting material hot forging turning shrink diameter(half thread)thread rolling make heat treatmentFinish Packing



Product Grade


Grade 8S Grade 10s



Materials and Chemical compstition




C Si Mn P S Cr Ni Cu
0.34 0.13 0.73 0.012 0.002 0.02 0.01 0.02






C Si Mn P S Cr Ni Cu
0.45 0.23 0.58 0.014 0.006 0.057 0.008 0.016



C Si Mn P S Cr Ni Cu
0.4 0.21 0.54 0.015 0.008 0.95 0.02 0.02
















Packing in small boxes according to customer’s requirements

Packing in plastic bag according to customer’s requirements




EURO Pallet





The advantages of QBH

  • QBH brand sales to the main quality assurance.
  • Years of export trade management, excellent service, word-of-mouth guarantee.
  • By working with TUV,escort for quality.
  • Customization of non-standard parts can be made according to customer's requirements and drawings.
  • For quality customers,we can provide a certain credit period.




In brief Type 3 grade A325 bolts shall be marked “A325” to distinguish them from standard grade A325s. Likewise Grade A490 bolts are available in diameters from 1/2 to 1-1/2 inch diameters with a minimum tensile strength of 150,000 PSI for all diameters, and are offered in two types.

In Fact ASTM A325 is an ASTM International standard for heavy hex structural bolts, titled Standard Specification for Structural Bolts, Steel, Heat Treated, 120/105 ksi Minimum Tensile Strength. It defines mechanical properties for bolts that range from 12 to 1 12 inches (13 to 38 mm) in diameter.

In accordance with ASTM A325, all threaded components of the fastener assembly must be galvanized by the same process and the supplier’s option is limited to one process per item with no mixed processes in a lot.



This Specification deals principally with two strength grades of high-strength
bolts, ASTM A325 and A490, and with their design, installation and inspection in
structural steel joints. Equivalent fasteners, however, such as ASTM F1852
(equivalent to ASTM A325) twist-off-type tension-control bolt assemblies, are
also covered. These provisions may not be relied upon for high-strength fasteners
of other chemical composition, mechanical properties, or size. These provisions do
not apply when material other than steel is included in the grip; nor are they
applicable to anchor rods.
This Specification relates only to the performance of fasteners in structural
steel joints and those few aspects of the connected material that affect this
performance. Many other aspects of connection design and fabrication are of equal
importance and must not be overlooked. For more general information on design
and issues relating to high-strength bolting and the connected material, refer to
current steel design textbooks and the Guide to Design Criteria for Bolted and
Riveted Joints, 2 nd Edition (Kulak et al., 1987).