ASTM A325 / a325m large hexagon bolt, heavy hexagon head bolt
Product Description:
Hexagonal bolts, also known as hexagonal head screws, hexagon head
bolts, hexagon head screws, hexagon screws or mechanical bolts, are
a common choice in construction and maintenance.Hexagon head bolts,
commonly known as hexagon head cap screws, are bolts with hexagonal
or six-sided heads.Hexagon bolts have six heads, which is the
industry standard for forged head bolts.A common feature of
hexagonal head screws is the surface of the gasket directly below
the head to produce a better seal.A hexagon head screw bolt is
actually produced within a tighter tolerance range and can be used
anywhere with a hexagon head bolt.
Several concepts about high strength bolts 1. According to the
specification of bolt performance class 8.8 or above, called high
strength bolt. The current national standard only listed to M39,
for large size specifications. In particular, the length of
high-strength bolts more than 10, 15 times, the domestic production
is still short.
Distinction between high strength bolts and ordinary bolts
High-strength bolts are larger than ordinary bolts of the same
specification.
The material for ordinary bolts is made of Q 235 (A 3).
High-strength bolt material 3 steel or other high-quality
materials, made after heat treatment, improve the strength.
The difference between the two is the difference in the strength of
the material.
From the perspective of raw materials:
The high strength bolt is made of high strength material. The
screw, nut and gasket of high strength bolt are made of high
strength steel. 35CrMoA, etc. Common bolts are made of Q235 steel
(equivalent to A 3 in the past).
From the strength grade point of view: high strength bolts,
increasingly widely used. Commonly used 8.8s and 10.9s two strength
grades, in which 10.9 grade is the majority, ordinary bolt strength
grade should be low, generally 4.4 grade. Grade 4.8, grade 5.6 and
grade 8.8.
Specification:
Details |
Name | A325m large hexagon bolt, |
Materials | Carbon Steel |
Head type | Hex |
Size | Diameter M6-M20 |
Standard | A325 |
Surface | Plain |
Packing | Inner packing in box,then in carton |
Delivery terms | FOB / CFR / CIF etc.
|
CHEMICAL COMPOSITIONG |
Group | C | Si | Mn | P | S | Cr | Mo | Ni | Cu | Characteristic |
304-A2 | 0.1 | 1 | 2 | 0.05 | 0.03 | 15-20 | | 8-19 | 4 | Medium hardening rate, suitable for general cold processing and
stretching, cold processing performance is good, commonly used for
external hexagonal bolts, nuts and gaskets products. |
|
316-A4 | 0.08 | 1 | 2 | 0.045 | 0.03 | 16.18.5 | 2-3 | 10-15 | 1 | Adding molybdenum, corrosion resistance is better than 304,
especially suitable for seawater and chemical media, more corrosion
resistance and pitting resistance. |
|
Application:
Friction type high strength bolt: suitable for steel frame
structure beam, column connection, solid web beam connection, heavy
crane beam connection of industrial workshop, brake system and
important structure under dynamic load.
High strength Bolts: shear connections in structures that allow for
a small amount of sliding or are subjected to indirect dynamic
loads.
Tensile high strength bolts: when the bolts are pulled, the fatigue
strength is low. Under dynamic load, its bearing capacity is not
more than 0.6P (P is the allowable axial force of bolts).
Therefore, it is only suitable for static loading, such as flange
butt joint, T type joint and so on.