B27081/28AZ - S.A.E. Standard Clevis Pin - 3/4 Diameter x 2-3/64 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

Technical Deep Dive: S.A.E. Standard Clevis Pin - 3/4 Diameter x 2-3/64 Inch Long

The S.A.E. Standard Clevis Pin, with its precise dimensions of 3/4 inch diameter and 2-3/64 inch overall length, represents a critical component in numerous mechanical and structural applications. Manufactured by Buyers Products, this clevis pin adheres rigorously to Society of Automotive Engineers (SAE) standards, ensuring exceptional quality, dimensional accuracy, and performance consistency. This detailed exposition will delve into the engineering specifics, material science, surface treatments, and diverse applications that underscore the functionality and reliability of this essential fastening element.

Adherence to S.A.E. Standards: The Foundation of Reliability

The designation "S.A.E. Standard" is not merely a label but a testament to a commitment to engineering excellence. The Society of Automotive Engineers (SAE) develops and publishes technical standards for a wide range of engineering applications, particularly in the automotive, aerospace, and commercial vehicle industries. For fasteners like clevis pins, SAE standards typically govern critical aspects such as material composition, mechanical properties (e.g., tensile strength, shear strength), dimensional tolerances, surface finishes, and testing methodologies. Adherence to these standards ensures several key benefits:

• Interchangeability: Components manufactured to SAE standards are designed to be interchangeable, facilitating maintenance, repair, and assembly processes across various systems and manufacturers. This pin’s 3/4-inch diameter is a standard size, ensuring compatibility with a vast array of mating components.
• Performance Assurance: Standardized material grades and manufacturing processes mean that the clevis pin will exhibit predictable mechanical properties under specified load conditions, offering engineers confidence in its structural integrity and operational lifespan.
• Safety: By establishing minimum performance criteria, SAE standards contribute directly to the safety of assembled systems, reducing the risk of component failure in critical applications.
• Quality Control: Manufacturing processes are often guided by SAE quality specifications, leading to higher product consistency and reduced defect rates.

For clevis pins, specific SAE standards like SAE J494 (Clevis Pins) often dictate the nominal dimensions, material grades, and other attributes, ensuring that this Buyers Products clevis pin meets or exceeds the industry's most stringent requirements for robust performance.

Material Selection and Manufacturing Process

While the specific material composition is not explicitly listed, SAE standard clevis pins are predominantly manufactured from high-strength steels, chosen for their excellent balance of ductility, tensile strength, and shear resistance. Common materials include low-carbon steels (e.g., AISI 1018, 1020) for general-purpose applications, medium-carbon steels (e.g., AISI 1045) for higher strength requirements, or alloy steels where extreme loads or specific environmental resistances are needed. Stainless steels (e.g., 304, 316) may be used for superior corrosion resistance, though typically with a premium cost and sometimes different mechanical properties.

The manufacturing process for clevis pins typically involves cold heading or machining. Cold heading is a highly efficient process where a wire or rod is cut to length and then plastically deformed in dies at room temperature to form the head and shaft. This process strengthens the material through work hardening and produces a consistent grain flow, enhancing the pin's fatigue resistance and overall strength, particularly in the critical head-to-shaft transition area. Precision machining, conversely, involves cutting the pin from bar stock. While potentially offering tighter tolerances for specific features, it can be more costly for high volumes and may not achieve the same work-hardened benefits as cold heading unless subsequent heat treatment is applied.

Following the primary forming operation, the pin undergoes secondary operations such as drilling the cotter pin hole, chamfering edges, and surface finishing. Each step is meticulously controlled to ensure that the final product adheres to the precise dimensional and quality specifications.

Detailed Dimensional Analysis and Tolerances

The provided specifications are crucial for understanding the exact fit and function of this clevis pin. Each dimension plays a vital role in its intended application:

• (0) Drill No. 19 (.166): This specifies the drill bit size used for creating the cotter pin hole. A No. 19 drill bit has a diameter of 0.166 inches. This dimension ensures proper clearance for the retaining element.
• A: 0.750 inches (3/4 inch Nominal Diameter): This is the fundamental diameter of the pin's shank. This dimension is paramount for fitting the pin through mating holes in the components it connects. Precise manufacturing tolerances around this nominal value are critical to ensure a snug fit that minimizes play and wear while allowing for easy insertion and removal. Excessive play can lead to premature wear of both the pin and the surrounding components, reducing the lifespan of the assembly.
• B: 0.938 inches: This dimension likely represents the diameter of the clevis pin's head. The head provides a bearing surface against one side of the assembly, preventing the pin from passing entirely through the connected components. A larger head diameter generally distributes load over a greater area, reducing localized stress on the connected component.
• C: 0.250 inches: This dimension could refer to the thickness of the pin's head or a specific critical measurement related to the head's geometry, such as the radius of the fillet under the head. A robust head thickness is essential for resisting shear forces and ensuring the pin remains securely seated. If it's a fillet radius, it helps mitigate stress concentrations at the junction of the head and shank.
• D (Min.): 1.750 inches: This dimension specifies the minimum grip length or usable length of the pin. The grip length is the maximum combined thickness of the components that the clevis pin is designed to secure effectively, ensuring that the cotter pin hole is exposed and accessible after insertion. The "Min." designation emphasizes that assemblies totaling 1.750 inches or less in thickness can be securely fastened by this pin, leaving sufficient clearance for cotter pin insertion.
• E: 2.047 inches: This is the length from the underside of the pin's head to the centerline of the cotter pin hole. This dimension is crucial for calculating the precise location where the cotter pin will reside, ensuring it aligns correctly with the exit hole of the mating component and provides proper retention.
• F: 2.297 inches (Overall Length): This represents the total length of the clevis pin from the underside of the head to the tip of the shaft. This dimension is essential for overall clearance considerations within an assembly and for determining storage and handling requirements. The length of 2-3/64 inches mentioned in the title (which is approximately 2.047 inches, matching E) is likely referring to the effective length under the head to the cotter pin hole, while F is the absolute overall length. Given 2-3/64" converts to 2.046875", it's highly probable the title refers to dimension 'E', which is the critical effective length.
• G: 0.156 inches: This dimension indicates the nominal diameter of the cotter pin *accommodated* by the clevis pin hole. While the hole is drilled with a No. 19 (.166 inch) drill for clearance, the "G" dimension often refers to the standard size of the cotter pin (e.g., a 5/32-inch cotter pin, which is 0.15625 inches) that fits snugly but freely through the drilled hole. This ensures that the appropriate retaining hardware can be easily specified and installed.

The combination of these precise dimensions, held to tight manufacturing tolerances, guarantees a high-performance clevis pin capable of forming secure, pivotable connections in demanding environments.

Advanced Surface Treatments: Zinc and Cadmium Plating

Surface treatments are integral to enhancing the durability, corrosion resistance, and specific functional attributes of clevis pins. Buyers Products offers these pins with either a cadmium-plated or zinc-plated finish, each possessing distinct characteristics and application suitability.

Zinc Plated Clear (as specified)

Zinc plating, specifically "Zinc Plated Clear," is a widely utilized and cost-effective method for protecting steel components from corrosion. The process involves electrodepositing a thin layer of zinc onto the steel substrate. Key aspects include:

• Corrosion Protection: Zinc acts as a sacrificial coating. When exposed to corrosive environments, the zinc preferentially corrodes before the underlying steel, providing galvanic protection. This significantly extends the lifespan of the clevis pin in outdoor or moderately corrosive conditions.
• Passivation (Clear Chromate): After zinc plating, a clear chromate conversion coating is applied. This passivation layer reacts with the zinc to form a protective film that further enhances corrosion resistance, particularly against "white rust" (zinc corrosion products). The "clear" designation means the finish retains a bright, silvery appearance, which is aesthetically pleasing and offers good reflectivity.
• Benefits: Excellent adhesion, good wear resistance, and a visually appealing finish. It is generally more environmentally friendly than cadmium plating and compliant with modern environmental directives such as RoHS (Restriction of Hazardous Substances) and REACH (Registration, Evaluation, Authorisation and Restriction of Chemicals).
• Applications: Commonly used in automotive, agricultural, construction, and general industrial applications where moderate corrosion protection is required without the need for extreme durability in harsh saltwater or highly acidic/alkaline environments.

Cadmium Plating

Cadmium plating is a highly specialized surface treatment known for its exceptional protective qualities, though its use has become more restricted due to environmental and health concerns associated with cadmium compounds. When specified, cadmium plating offers:

• Superior Corrosion Resistance: Cadmium provides outstanding corrosion protection, particularly in marine and saltwater environments. It forms a highly stable oxide layer and offers excellent galvanic compatibility with aluminum, which is common in aerospace applications.
• Lubricity: Cadmium possesses inherent lubricious properties, which reduces the coefficient of friction, making it suitable for applications where components need to rotate or slide smoothly, even under load, and where repeated assembly/disassembly is common. This lubricity can prevent galling (cold welding) between mating parts.
• Low Electrical Contact Resistance: This makes it suitable for certain electrical connection applications where good conductivity is required even after prolonged exposure.
• High Temperature Performance: Cadmium retains its protective properties at relatively high temperatures compared to some other platings.
• Environmental Considerations: Due to the toxicity of cadmium, its use is heavily regulated. Many industries are actively seeking alternatives to cadmium plating where possible. However, it remains critical in specific high-reliability sectors like aerospace and military, where no equally effective substitute has been found for certain applications.
• Applications: Aerospace, military hardware, and specialized marine equipment where its unique combination of corrosion resistance and lubricity is indispensable.

The choice between zinc and cadmium plating depends critically on the specific application's environmental conditions, required performance characteristics, and regulatory compliance considerations.

Diverse Industrial Applications

The 3/4-inch diameter SAE Standard Clevis Pin is a versatile component indispensable across a myriad of industries, facilitating secure and pivotable connections. Its robust design and adherence to standards make it suitable for a wide range of demanding applications:

• Automotive and Commercial Vehicles: Clevis pins are extensively used in trailer hitches, towing mechanisms, braking systems (e.g., connecting brake rods), steering linkages, hydraulic cylinder attachments (e.g., dump truck hoists, snowplow articulation), and various control linkages within heavy-duty trucks and utility vehicles.
• Agriculture: Farm machinery relies heavily on clevis pins for connecting implements to tractors (e.g., three-point hitches, drawbars), articulating mower decks, securing hydraulic cylinder rods on loaders and plows, and linking various components in seeding, harvesting, and tillage equipment. Their ease of use facilitates quick changes of attachments in the field.
• Construction Equipment: Heavy construction machinery such as excavators, bulldozers, backhoes, and cranes utilize clevis pins for connecting buckets, booms, hydraulic cylinders, and other critical articulating components. They provide robust pivot points capable of withstanding high shear loads and dynamic stresses.
• Material Handling and Lifting: In forklifts, cranes, hoists, and conveyor systems, clevis pins are employed to connect lifting attachments, securing loads, and forming pivot points in articulated arms or trolleys. They are crucial in applications requiring reliable load transfer and movement.
• Marine Applications: For boat rigging, davits, anchor systems, and boat trailers, clevis pins made from corrosion-resistant materials (or cadmium-plated for extreme environments) provide essential connections that can withstand harsh saltwater exposure and dynamic forces.
• Industrial Machinery: General industrial equipment, including presses, automated assembly lines, processing machinery, and conveying systems, utilize clevis pins for a variety of tasks, from connecting sensor arms and actuators to forming robust hinges and linkages.
• Structural and Rigging: Clevis pins are also found in scaffolding, temporary structures, and various rigging setups where a strong, easily removable, and reusable fastener is required for connecting chains, cables, and structural elements.

The ability of this clevis pin to operate effectively as both a fastening element and a pivot point, combined with its resistance to shear forces, makes it invaluable in dynamic mechanical systems.

Functional Principles and Installation Best Practices

The fundamental function of a clevis pin is to provide a secure, yet often pivotable, connection between two or more components (typically a clevis and an eye, or a yoke and an eye) while resisting shear forces. When installed, the pin passes through aligned holes in the components, and a retaining element—such as a cotter pin, hairpin cotter, or R-clip—is inserted through the transverse hole (the cotter pin hole) at the exposed end of the clevis pin. This prevents the pin from dislodging, thereby maintaining the connection.

Key functional principles:

• Shear Resistance: Clevis pins are primarily designed to resist shear stress, which occurs when forces act parallel to the pin's cross-section, attempting to cut it. The 3/4-inch diameter of this pin provides substantial cross-sectional area, directly correlating to its shear strength.
• Pivot Point: Unlike bolts which often create rigid connections, clevis pins facilitate relative rotation or angular movement between connected components. This makes them ideal for joints that require articulation, such as those found in hydraulic cylinders or control linkages.

Installation best practices are critical for ensuring optimal performance and safety:

• Correct Sizing: Always match the clevis pin diameter to the hole diameter of the mating components. A proper fit minimizes play and wear.
• Full Engagement: Ensure the clevis pin fully passes through all components and that the cotter pin hole is completely clear on the other side.
• Appropriate Retainer: Use a cotter pin or other retaining clip of the correct size (as indicated by dimension G and Drill No.) and material. Always bend or secure the cotter pin ends properly to prevent accidental removal.
• Regular Inspection: Periodically inspect clevis pins for signs of wear, deformation, corrosion, or damage. Replace any pin exhibiting signs of fatigue, bending, or significant material loss.
• Lubrication: In applications with high articulation or exposure to moisture, consider using appropriate lubricants to reduce friction and extend the lifespan of the pin and mating components.

Buyers Products: Commitment to Quality and Availability

Buyers Products is renowned for its commitment to manufacturing high-quality, reliable components for a vast array of industries. The S.A.E. Standard Clevis Pin is a testament to this dedication, produced with meticulous attention to detail and stringent quality control measures to ensure every pin meets the exacting specifications. The availability of multiple sizes ensures that engineers and procurement professionals can find the exact fit for their unique applications, while the option for cadmium- or zinc-plated finishes allows for tailored corrosion protection based on environmental demands.

Furthermore, the ability to order these pins in quantities to your specification underscores Buyers Products' flexibility and focus on meeting customer needs, whether for small-scale repair projects or large-volume production runs. This ensures seamless integration into supply chains and project timelines.

Conclusion

The S.A.E. Standard Clevis Pin, with its 3/4-inch diameter and 2-3/64-inch length, represents a fundamental yet highly engineered component. Its adherence to stringent SAE standards, coupled with precise dimensional control, choice of advanced surface treatments, and robust material selection, guarantees a product of exceptional reliability and performance. From heavy-duty automotive linkages to critical agricultural machinery and complex industrial assemblies, this clevis pin from Buyers Products provides a secure, pivotable connection that withstands demanding operational conditions. Its technical specifications and manufacturing integrity make it an indispensable fastening solution for engineers prioritizing durability, safety, and operational efficiency in their designs.