8.8-grade Hexagon Fit Shank Bolts

The 8.8-grade Hexagon Fit Shank Bolts (GB/T 27 standard) are manufactured by quenching and tempering of medium carbon alloy steel. Their overall strength meets the 8.8 grade mechanical performance standard. The middle section of the screw has a precise smooth surface mating section. It is positioned by the close fit between the smooth rod and the workpiece's threaded hole. This is different from ordinary bolts which rely solely on the thread for locking. It can not only transmit axial tension but also withstand lateral shear force. It has high positioning accuracy and is not prone to misalignment or slippage after assembly. It is mostly used in high-precision jointing of equipment and heavy-load stressed connection parts.

Product Feature

Precise positioning, anti-loosening and anti-movement: The bare shaft section is closely fitted with the installation hole, which can perfectly eliminate the relative displacement between components, ensuring the coaxiality and stability of the equipment operation, and eliminating the offset phenomenon that is prone to occur with ordinary bolts.

Outstanding shear-bearing capacity: When subjected to lateral shear force, it relies on the shear strength of the bolt itself and the extrusion strength of the hole wall to bear the load, without overly relying on the huge preload friction force. Its lateral shear capacity far exceeds that of ordinary bolts of the same specification.

High strength and stability: The 8.8 grade strength level ensures that it has excellent tensile-pulling performance and hardness, and can maintain a stable connection even in mechanical structures under large stress or slight vibration.

Efficient assembly, protecting the workpiece: When used in conjunction with countersunk holes, the installation process is smooth. Unlike ordinary bolts, no large hole diameter needs to be reserved or a large amount of anti-loosening glue needs to be applied, and it can avoid abnormal wear of the bolt head and the workpiece surface.

Our Strength

·  Direct from manufacturer to customer, On time delivery

·  Completely fastener products,offers one - stop shopping service.

·  High quality and competitive price, saving your cost.

·  Product complies with iso9001 and ts16949 certification

·  After shippment, we will offer the Material report and Test report.

Product Application

The 8.8 grade threaded hole screws are widely used in various high-end mechanical equipment, automotive manufacturing, heavy steel structures, mold assembly, and automated production lines. They are particularly suitable for critical connection parts that require extremely high positional accuracy and need to withstand large lateral loads or frequent vibrations, such as the main shaft of machine tools, the gearbox housing, the fixed part of the transmission shaft, and the mold clamping positioning of large-scale molds.

Send Inquiry

Please feel free to fill your inquiry in the form below. We will reply you in 24 hours.

Q: Are you trading company or manufacturer ?

A: We are factory

Q: How long is your delivery time?

A: Generally it is 2-5 days if the goods are in stock. or it takes around 20 days if the goods are not in stock, certainly,it is according to your quantity.

Q: Do u do Non-standard Fasteners,and How about the OEM/ODM?

A:Yes,we do Non-standard Fasteners,OEM/ODM as well,and we have 20 years more experience in this line.We have complete production line, R&D Center. Pre-sales and after-sales support. Let u no worries about the quality.

Q: Do you provide samples ? is it free or extra ?

A: Yes, we could offer the sample for free,but u need charge the freight at the first time.

Q:Do you sell little quantity,like few hundred and few thousand?

A: It depends on the stock. if we have ,that's ok. if not,it needs MOQ.