What is ASTM A325 bolts ?

ASTM A325 bolts are standard for mezzanine threaded hexagonal structural bolts manufactured in three different grades or with “T”, “M”, “TC” tails for special cases:

• Type 1 – Carbon, boron, or medium carbon alloy steels undergo heat treatment to achieve the desired mechanical properties. Type 1 is the most commonly specified and possibly the most commercially available. The head is a thick hexagonal pattern and these bolts will have a thread length set based on the required diameter.
• Type 2 – This type was recalled in November 1991.
• Type 3 – Heat resistant steel, quenched and heat treated. Although the strength is the same as Type 1, Type 3 bolts are made from heat resistant steel containing copper, chromium and nickel. This forms an oxide coating that protects the base material from corrosion.
• A325T – A325Full thread. A325T bolts shall be no more than four times the diameter. For example, a 3/4 A325T bolt should not exceed 3″ in length (four times 3/4″) and a 1″ diameter A325T bolt should not exceed 4 ″
• A325 TC -Self-break bolt
• A325M – Bulong A325 metric.

Application

ASTM A325 standard bolts are commonly used in the steel structure industry, bridges, telecommunications, joints that need to bear large forces, complex structural positions, high pressure pipeline connections, connections in the machinery and equipment with large loads, etc. It is the ideal product for the installation of wind turbines, the best towers today.

ASTM A325 . Bolt Standard Specifications

Size

Diameters ½ – 1½”, lengths from 4″ to 10″. Although the head size of the A325 bolt is the same as any standard head screwdriver ASME B18.2.6 2010, but has a shorter thread length than most other structural bolts.

Size	D	F			C		H			T
	Body Diameter	Width Edge (Nuts)			Peak Width (Nuts)		Head Thickness			Thread length
	Max	Basic	Max	Min	Max	Min	Basic	Max	Min	Basic
½	0.515	⅞	0.875	0.85	1.010	0.969	⁵⁄₁₆	0.323	0.302	1
⅝	0.642	1¹⁄₁₆	1.062	1.031	1.227	1.175	²⁵⁄₆₄	0.403	0.378	1.25
¾	0.768	1¼	1.250	1.212	1.443	1.383	¹⁵⁄₃₂	0.483	0.455	1.38
⅞	0.895	1⁷⁄₁₆	1.438	1.394	1.660	1.589	³⁵⁄₆₄	0.563	0.531	1.5
1	1.022	1⅝	1.625	1.575	1.876	1.796	³⁹⁄₆₄	0.627	0.591	1.75
1⅛	1.149	1¹³⁄₁₆	1.812	1.756	2.093	2.002	¹¹⁄₁₆	0.718	0.0658	2
1¼	1.277	2	2	1.938	2.309	2.209	²⁵⁄₃₂	0.813	0.749	2
1⅜	1.404	2³⁄₁₆	2.188	2.119	2.526	2.416	²⁷⁄₃₂	0.878	0.810	2.25
½	1.531	2⅜	2.375	2.3	2.742	2.622	¹⁵⁄₁₆	0.974	0.902	2.25

Unit: Inch

Mechanics

Due to being used in many different industries, in Vietnam, ASTM A325 bolts are used in both Inch and Meter systems (A325M) and are tested for quality with a method consistent with industry standards. Unit conversion: 1In = 25.4mm; 1Psi = 6.89Mpa

Size	Tensile trength  ksi	Yield strength ksi	Elongation %	RA %
½ – 1	Min 120	Min 92	14	35
1⅛ – 1½	Min105	Min 81	14	35

Inch

Size	Tensile trength MPA	Yield strength MPA	Elongation %	RA %
M16 – M36	830	660	14	35

Chemistry

Ingredient	C	Manganese	Phosphorus	Sulfur	Silicon	Boron
%	0,30 – 0,52	Min 0.60	Max 0.035	Max 0.040	0.15 – 0.30	Max 0.003

Nut – Washer included

Bolts	Nuts	Washer
A325	A563 or A194 2H	F436 or F959
A325M	A563M or A194 2HM	F436M or F959M