Hex Head Cap Screw Grade 8
1/4" to 1-1/2"
Rockwell Hardness - C33 to C39
Proof Load Strength - 120,000 psi
Tensile Strength Minimum - 150,000 psi
Grade Markings - 6 Radial Lines 60 Degrees Apart
Grade 8 fasteners are made from high-strength carbon alloy steel and are designed to withstand extreme stress and pressure. With a tensile strength of 150,000 psi, Grade 8 fasteners are ideal for heavy-duty applications, such as automotive assemblies, structural steel, and heavy machinery. When these fasteners are finished with plain plating, they are provided with a minimal coating or left uncoated, exposing the steel to the environment. Plain-plated Grade 8 fasteners are typically chosen for applications where maximum strength, precision, and cost-effectiveness are essential, but corrosion resistance is not a primary concern.
The benefits of plain plating in Grade 8 fasteners are clear, especially in environments where the primary goal is to maintain the fastener's mechanical properties. The absence of coatings, such as zinc or other corrosion-resistant layers, ensures that the fastener maintains its original strength and threading characteristics. This is particularly important in applications where tight tolerances and high-performance standards are required, such as in critical structural components, machinery, or automotive systems. The lack of plating also allows for more accurate torque applications, as there is no interference from extra layers of coating, which might affect the fastener's fit or tightening.
Another significant benefit of plain plating is weldability. When fasteners are uncoated or have minimal plating, they are more suitable for welding applications, as coatings can interfere with the welding process. Plain-plated fasteners allow for better heat transfer during welding, making them ideal for custom or repair work that involves high-temperature processes.
However, the lack of plating does come with trade-offs, particularly in terms of corrosion resistance. Plain-plated Grade 8 fasteners are more susceptible to rust and degradation when exposed to moisture or harsh environments. As such, they are typically used in indoor or controlled settings where corrosion protection is less of a concern, or in applications where fasteners can be regularly maintained.
In summary, plain-plated Grade 8 fasteners offer superior mechanical performance, cost-effectiveness, and versatility, making them suitable for demanding applications where strength and precision are the primary considerations.
