B27081/210C - S.A.E. Standard Clevis Pin - 5/8 Diameter x 1-3/4 Inch Long

Buyers Products Clevis Pin is manufactured to SAE standards and available in multiple sizes to fit your application. The clevis pin is used with rods, cables, yoke ends, and other assemblies. It can be ordered with a cadmium- or zinc-plated finish in quantities to your specification.

Specifications

The S.A.E. Standard Clevis Pin, precisely engineered with a 5/8-inch diameter and 1-3/4-inch length, represents a fundamental component in mechanical assemblies requiring secure, yet articulating, connections. This product embodies adherence to the rigorous standards set forth by the Society of Automotive Engineers (SAE), ensuring a high degree of dimensional consistency, material integrity, and predictable performance across diverse applications. As a critical fastener, the clevis pin serves to connect two or more components, typically a clevis or yoke, allowing for rotational movement about its axis while resisting shear forces. Its design facilitates quick assembly and disassembly, particularly when paired with an appropriate retaining element such as a cotter pin or hairpin clip.

Understanding the S.A.E. Standard and Its Significance

The term "S.A.E. Standard" is paramount in the specification of this clevis pin. SAE International is a global association of engineers and technical experts in the aerospace, automotive, and commercial vehicle industries. Their standards are developed through a consensus-based process, drawing upon extensive industry experience and scientific research. For fasteners like clevis pins, SAE standards define crucial parameters including material composition, mechanical properties (e.g., tensile strength, shear strength, hardness), dimensional tolerances, surface finish requirements, and testing methodologies. Adherence to these standards is not merely a matter of compliance but a guarantee of interoperability, safety, and reliability. When a clevis pin is manufactured to SAE standards, it assures users that the component will fit as intended with other SAE-compliant parts, perform predictably under specified loads, and withstand anticipated environmental conditions, thereby minimizing the risk of premature failure and maximizing the lifespan of the entire assembly. This standardization is critical in applications where components from multiple manufacturers must function seamlessly together, as often seen in automotive, agricultural, and heavy equipment industries.

Detailed Dimensional Analysis of the 5/8" Diameter x 1-3/4" Long Clevis Pin

The specific dimensions of this clevis pin—5/8-inch diameter and 1-3/4-inch length—are critical for its intended applications. Let's delve into the provided specifications table to understand the precise geometry:

• A (0.625 inches): This value unequivocally defines the nominal diameter of the pin shaft, corresponding precisely to 5/8 inch. This dimension is crucial for ensuring a proper fit within the bores of the components it connects. A precise diameter is essential to prevent excessive play (which could lead to wear and fatigue) or interference (which would prevent assembly).
• E (1.750 inches): This represents the functional length of the pin, measured from the underside of the head to the end of the pin shaft. This is the overall length of the pin that passes through the connected components and extends sufficiently to accommodate a retaining pin.
• D (Min. 1.625 inches): Designated as the minimum grip length, this dimension is vitally important. The grip length refers to the maximum effective thickness of the material that the clevis pin can securely fasten, allowing enough protrusion for the cotter pin hole. A minimum grip length of 1.625 inches indicates that this pin is ideally suited for connecting components with a combined thickness up to approximately 1-5/8 inches, while still leaving adequate space for the retaining pin.
• (0) Drill No. 29 (0.136 inches): This specification details the diameter of the hole drilled through the pin, intended for the insertion of a cotter pin or other retaining device. A #29 drill bit creates a hole with a diameter of 0.136 inches, which is typically designed to accommodate a standard 1/8-inch (0.125-inch) diameter cotter pin, providing a slight clearance for ease of insertion. The precise placement of this hole relative to the pin's length and head ensures secure retention of the assembly.
• B (0.813 inches): This is the diameter of the pin's head. The head provides a bearing surface against one side of the clevis, distributing the load and preventing the pin from passing completely through the assembly. Its larger diameter prevents accidental pull-through.
• C (0.188 inches): This indicates the thickness of the pin's head. Combined with the head diameter, this dimension contributes to the overall strength and load-bearing capability of the head itself, ensuring it can withstand the forces exerted against it.
• F (1.953 inches): This dimension represents the total overall length of the clevis pin, encompassing both the shaft and the head thickness. It is typically measured from the top surface of the head to the end of the pin shaft. (Note: E + C = 1.750 + 0.188 = 1.938 inches. The slight discrepancy with F (1.953 inches) might be due to manufacturing tolerances, specific measurement points, or a minor chamfer/radius not explicitly accounted for in the E+C calculation, but it confirms F as the total length.)
• G (0.062 inches): While not explicitly defined, "G" typically refers to a chamfer or radius present on the pin. This could be a chamfer on the end of the pin to facilitate easier insertion into the clevis or a radius under the head to reduce stress concentrations and improve fatigue life. A 0.062-inch (1/16 inch) dimension for a radius or chamfer is common in fastener design.

These precise dimensions, all conforming to SAE standards, ensure that the pin functions optimally within its specified operational parameters, providing reliable mechanical linkage.

Material Selection and Mechanical Properties

The fundamental performance of a clevis pin is inherently tied to its base material. While specific material grades may vary, clevis pins manufactured to SAE standards are typically produced from carbon steel, offering a balance of strength, ductility, and cost-effectiveness. Common grades often include low to medium carbon steels (e.g., SAE 1010, 1018, or 1045). These steels provide the necessary mechanical properties to withstand the predominant shear stresses experienced by a clevis pin. Key mechanical properties include:

• Tensile Strength: The maximum stress a material can withstand before breaking when stretched. While clevis pins primarily experience shear, tensile strength is an indicator of overall material integrity.
• Yield Strength: The stress at which a material begins to deform plastically (permanently). This is critical for preventing permanent bending or deformation under load.
• Shear Strength: The material's resistance to forces that cause parallel planes of material to slide past each other. This is arguably the most critical property for a clevis pin, as it is primarily designed to resist shear forces within the joint.
• Hardness: Resistance to indentation and abrasion. Sufficient hardness contributes to wear resistance, particularly important in articulating joints.

For applications demanding superior corrosion resistance or higher strength, materials such as alloy steels or various grades of stainless steel (e.g., 304 or 316) may be utilized. The selection of the base material is always guided by the anticipated environmental conditions, the magnitude of the applied loads, and the required service life of the component.

Advanced Surface Finishes: Enhancing Durability and Longevity

To further augment the performance and extend the service life of clevis pins, especially in corrosive or demanding environments, advanced surface finishes are applied. This S.A.E. Standard Clevis Pin is available with two primary options: Zinc Plated (Clear) or Cadmium Plated. Each finish offers distinct advantages and is suited for specific applications.

Zinc Plating (Clear Passivation)

Zinc plating, often referred to as electrogalvanizing, is a widely adopted and cost-effective method for protecting steel components from corrosion. The process involves submerging the clevis pin in an electrolyte bath containing dissolved zinc salts, through which an electric current is passed. This causes a thin, uniform layer of zinc to deposit onto the steel surface. Zinc acts as a sacrificial coating; being more electrochemically active than steel, it preferentially corrodes, thereby protecting the underlying steel from rust and oxidation even if the coating is scratched or minorly damaged.

The "Clear" designation typically refers to a clear trivalent chromium passivation layer applied over the zinc coating. This passivation layer significantly enhances the corrosion resistance of the zinc, often providing a clearer, brighter appearance. Trivalent chromium passivation is a modern alternative to older hexavalent chromium processes, which are now largely restricted due to environmental and health concerns (e.g., RoHS and REACH directives). The clear passivation helps to delay the formation of "white rust" (zinc corrosion products) and "red rust" (iron corrosion products), extending the component's aesthetic appeal and functional life. Zinc-plated clevis pins with clear passivation are suitable for a broad range of general industrial, agricultural, and automotive applications where moderate corrosion protection is required. They offer excellent resistance to atmospheric corrosion in typical outdoor and indoor environments, providing a balance of performance, cost, and environmental compliance.

Cadmium Plating

Cadmium plating is a historically significant and highly effective anti-corrosion finish, though its use has become more restricted due to environmental regulations. Cadmium provides exceptional corrosion resistance, particularly in marine and alkaline environments, outperforming zinc in certain harsh conditions. It offers excellent lubricity, which can be beneficial in applications where consistent torque and reduced friction are desired during assembly or operation. Furthermore, cadmium plating demonstrates superior galvanic compatibility with aluminum, making it a preferred choice in aerospace applications where steel fasteners are used in conjunction with aluminum structures.

The application process for cadmium plating is similar to zinc plating, involving electrodeposition. However, due to cadmium's toxicity and its classification as a hazardous substance, its application is tightly regulated and often limited to critical military, aerospace, or legacy industrial systems where its unique properties are indispensable and no suitable alternatives exist. While increasingly phased out in general commercial products, its availability for this clevis pin underscores its high-performance characteristics for demanding specifications where regulatory allowances are met. For applications requiring maximum corrosion protection and specific performance attributes where environmental considerations permit, cadmium plating remains a premium option.

Diverse Applications Across Industrial Sectors

The versatility and robust design of the S.A.E. Standard Clevis Pin make it an indispensable component across a multitude of industrial and commercial applications. Its ability to create a secure, yet flexible, pivot point is fundamental to many mechanical systems:

• Automotive and Transportation: Crucial for connecting various linkages in trailers (e.g., hitch connections, safety chain attachments), agricultural implements attached to tractors, control mechanisms in heavy-duty trucks, and suspension systems where limited articulation is required.
• Agricultural Machinery: Essential in connecting implements such as plows, cultivators, mowers, and trailers to tractors. They are used in lift arms, hydraulic cylinder attachments, and various pivot points where robust and easily detachable connections are needed for farm equipment.
• Construction Equipment: Found in excavators, bulldozers, loaders, cranes, and other heavy machinery. They secure buckets, attachments, booms, and other articulating components, enduring significant shear loads and harsh environmental conditions.
• Marine Applications: While cadmium plating is often preferred for superior saltwater resistance, zinc-plated pins can be used in freshwater or less exposed marine environments for rigging, anchoring systems, and boat trailer components.
• Material Handling: Used in conveyor systems, forklift attachments, and other lifting equipment where components need to pivot or be quickly interchanged.
• Industrial Machinery: Integral to various industrial automation systems, manufacturing equipment, and processing plants for linking levers, rods, and other moving parts.
• Rigging and Lifting: In non-critical or specified lifting applications, clevis pins can secure shackles, hooks, and other rigging hardware, though strict load limits and safety factors must be observed.
• General Fabrication and DIY: Due to their standardization and ease of use, they are also popular for custom fabrication projects, gate hinges, and other general-purpose mechanical connections.

The selection of the 5/8-inch diameter and 1-3/4-inch length for this specific pin caters to applications requiring a substantial load-bearing capacity and a certain grip length, making it suitable for medium to heavy-duty linkages.

Installation, Maintenance, and Operational Considerations

Proper installation and routine maintenance are paramount to maximizing the lifespan and ensuring the safe operation of any clevis pin assembly. When installing the S.A.E. Standard Clevis Pin, it is crucial to select a retaining element, such as a cotter pin or hairpin clip, that corresponds to the 0.136-inch (Drill No. 29) hole diameter. The retainer must be correctly inserted and spread (for cotter pins) or fully engaged (for hairpin clips) to prevent the clevis pin from dislodging during operation.

The fit between the clevis pin and the bores of the connected components is also critical. A slightly loose fit (clearance fit) is typically desired to allow for articulation and ease of assembly, but excessive clearance can lead to accelerated wear, fretting corrosion, and potential fatigue failure under dynamic loads. Conversely, an interference fit would prevent proper assembly or lead to excessive stress. The precise diameter of 0.625 inches (5/8 inch) ensures compatibility with standard clevis holes.

Regular inspection is recommended to identify any signs of wear, corrosion, bending, or other forms of damage. In articulating joints, friction can lead to wear on both the pin and the clevis bores; lubrication can help mitigate this. The chosen finish, whether zinc-plated or cadmium-plated, will provide a protective barrier against environmental degradation, but this coating can wear off over time, especially in high-friction areas or harsh environments, necessitating replacement. Adherence to the manufacturer's specified load limits and recommended safety factors is essential to prevent overloading and catastrophic failure, particularly in critical load-bearing applications.

Quality Assurance and Manufacturing Excellence

The manufacturing process for S.A.E. Standard Clevis Pins involves precision engineering to meet the stringent dimensional and material specifications. Quality assurance measures are integrated throughout the production cycle, beginning with the selection of raw materials. Material traceability ensures that the base steel meets the required chemical composition and mechanical properties. During fabrication, which often involves cold heading or machining, strict tolerances are maintained for all critical dimensions (diameter, length, head dimensions, and cotter pin hole placement). Advanced inspection techniques, including optical comparators, micrometers, and go/no-go gauges, are utilized to verify dimensional accuracy. Furthermore, batch testing may be conducted to confirm mechanical properties and the integrity of the applied surface finishes, such as salt spray testing for corrosion resistance. This commitment to quality assurance ensures that each S.A.E. Standard Clevis Pin consistently delivers the expected performance and reliability, making it a dependable choice for demanding industrial applications.

Conclusion: The Engineered Solution for Reliable Linkages

The S.A.E. Standard Clevis Pin, with its precise 5/8-inch diameter and 1-3/4-inch length, stands as a testament to engineered reliability. Its adherence to rigorous SAE standards guarantees dimensional accuracy, material strength, and consistent performance, making it an ideal choice for critical mechanical linkages. Whether specified with a durable zinc-plated (clear) finish for broad-spectrum corrosion protection or a cadmium-plated finish for specialized, high-performance requirements, this clevis pin is designed to provide secure, articulating connections across a vast array of industrial, automotive, and agricultural applications. Its robust design, coupled with the detailed specifications and quality manufacturing, ensures longevity and safety, underpinning the operational integrity of the systems it serves. For professionals seeking a dependable and compliant fastening solution for rods, cables, yoke ends, and other assemblies, this S.A.E. Standard Clevis Pin offers an unparalleled combination of precision, durability, and versatility.