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.
