7432 - H7 Series End Yoke 1-1/8 Inch Hex Bore

Buyers Products H7 Series End Yoke with Hex Bore is a strong, durable component for your flexible coupling needs. The yoke is compatible with other major manufacturers' medium duty driveline components. It comes in a variety of bore sizes and shapes to work with your system. The yoke is made of forged steel for strength and durability. It works with Buyers Products NB7A U-joints to provide smooth and continuous torque transfer. The H7 Series End Yoke is perfect for medium duty applications with the ability to handle up to 800 inch pounds of torque at 1,000 RPM (12 HP).

Specifications

The Buyers Products H7 Series End Yoke with a 1-1/8 Inch Hex Bore represents a critical component in the engineering of robust and efficient power transmission systems. Designed specifically for demanding medium-duty applications, this end yoke embodies a confluence of material science, precision manufacturing, and practical engineering, ensuring exceptional durability and reliable performance in environments where continuous torque transfer is paramount. While the primary product discussed here features a 1-1/8 inch hex bore, it's essential to note that it is part of a versatile series that includes various bore sizes and shapes, such as the 1-1/4 inch variant detailed in the specifications table, allowing for broad compatibility across diverse shaft configurations.

At its core, an end yoke serves as the interface between a power take-off (PTO) shaft, transmission output, or other rotating machinery, and a universal joint (U-joint) within a driveline system. The H7 Series distinguishes itself through its robust construction from forged steel, a material choice that significantly enhances its mechanical properties. Forged steel offers superior tensile strength, yield strength, and impact resistance compared to cast alternatives, attributed to the refined grain structure achieved during the forging process. This results in a component capable of withstanding high cyclical stresses, torsional loads, and shock impacts commonly encountered in industrial, agricultural, and commercial vehicle applications, thereby extending the operational lifespan of the entire driveline.

Engineering Excellence in Torque Transmission

The defining feature of this particular end yoke is its 1-1/8 inch hex bore. The hexagonal geometry provides a positive, non-slip connection with a corresponding hex shaft, which is inherently efficient in transmitting torque. Unlike traditional keyed shafts that rely on a single keyway to bear the entire torsional load, hex bores distribute the load across multiple faces, minimizing stress concentrations and reducing the risk of keyway shear or wallowing over time. This design choice contributes directly to the yoke's rated capacity of 800 inch-pounds of torque at 1,000 RPM, translating to approximately 12 horsepower. This impressive rating positions the H7 Series as an ideal solution for medium-duty power transmission needs, offering a significant margin of safety and performance under continuous operational conditions.

The effectiveness of the hex bore system is further complemented by the inclusion of a 3/8-16 set screw. Positioned strategically at a specified angle (referenced as "4" in the specifications, often indicating a quadrant or clock position relative to a datum), this set screw secures the shaft axially within the yoke, preventing unintended disengagement or movement under dynamic loads. The "End of Hub to Centerline of Set Screw Hole" dimension of 0.625 inches ensures adequate shaft insertion depth for secure engagement, optimizing the frictional and positive mechanical lock provided by the hex bore and set screw combination.

Seamless Compatibility and Driveline Integration

One of the significant advantages of the Buyers Products H7 Series End Yoke is its commitment to interchangeability. It is explicitly designed to be compatible with other major manufacturers' medium-duty driveline components. This cross-compatibility is crucial for maintenance, repair, and overhaul (MRO) operations, offering flexibility in sourcing and simplifying system integration. Engineers and technicians can confidently incorporate the H7 Series into existing systems or design new ones without being restricted to a single brand ecosystem, streamlining inventory management and reducing downtime.

The yoke's optimal performance is achieved when paired with Buyers Products NB7A U-joints. Universal joints are essential for accommodating angular misalignment between connected shafts, allowing for articulation while transmitting power. The specifications highlight a "Joint Angle" of 15 degrees. This value typically represents the maximum recommended operating angle for the U-joint connected to this yoke, within which the driveline can operate efficiently, with minimal vibration, heat generation, and wear. Exceeding this angle can lead to increased stress on components, accelerated wear, and undesirable torsional vibrations, often referred to as non-uniform velocity variations. The precise fit and robust design of the H7 yoke, in conjunction with the NB7A U-joint, ensures smooth and continuous torque transfer even across varying angular displacements, which is vital for maintaining consistent power delivery and reducing operational noise.

Material Science and Manufacturing Precision

The choice of forged steel for the H7 Series End Yoke is a deliberate engineering decision rooted in the requirements of demanding mechanical applications. Forging is a manufacturing process that involves shaping metal using localized compressive forces. This process refines the metal's grain structure, aligning it with the direction of stress flow, which results in a component with superior strength, fatigue resistance, and toughness compared to parts made via casting or machining from plate. The absence of internal voids, porosity, and inclusions commonly found in cast parts further enhances the reliability and longevity of the forged steel yoke.

The "Plain" finish indicates a natural, as-forged or lightly machined surface. While not offering inherent corrosion protection, this finish is often preferred in applications where the component may be painted or coated by the end-user to match specific aesthetic or environmental requirements. More importantly, the dimensional accuracy achieved through precise machining post-forging is paramount. The "Hub Dia (in.)" of 2.00 inches, for instance, is critical for proper seating and alignment with the U-joint bearings, ensuring smooth rotation and minimizing friction. Similarly, the "Center Line to End of Hub" measurement of 2.50 inches is a key dimensional parameter for driveline length calculations and maintaining correct component spacing within an assembly, directly impacting driveline balance and performance.

Applications and Performance Parameters

The H7 Series End Yoke with its 1-1/8 inch hex bore is ideally suited for a broad spectrum of medium-duty applications that demand both robust construction and efficient power transmission. These include, but are not limited to:

• Agricultural Machinery: Powering PTO shafts on cultivators, mowers, balers, and sprayers where shock loads and continuous operation are common.
• Industrial Equipment: Conveyor systems, pump drives, mixer drives, and various factory automation machinery requiring reliable torque delivery.
• Construction Equipment: Auxiliary drives on compact utility loaders, trenchers, and small concrete mixers.
• Light-to-Medium Duty Commercial Vehicles: PTO systems for hydraulic pumps, winches, or other auxiliary equipment on utility trucks, service vehicles, and municipal fleet vehicles.
• Marine Applications: Propulsion systems or auxiliary drives on smaller vessels where space and weight are considerations, but durability is non-negotiable.

The performance parameters – 800 inch-pounds of torque at 1,000 RPM (12 HP) – are not merely theoretical figures; they represent tested and validated capabilities under typical operating conditions. This rating ensures that the yoke can handle the power demands of its intended applications without premature failure, offering operators peace of mind and maximizing uptime. The design philosophy behind the H7 series emphasizes a balance between high strength-to-weight ratio and cost-effectiveness, delivering a premium component without unnecessary over-engineering for its designated duty class.

Deep Dive into Specifications

Let's elaborate on the critical specifications and their technical implications:

• Bore Dia/Width (in.): 1-1/4 (Hex): As noted, this specification refers to the flat-to-flat dimension of the hexagonal bore. For the product titled "1-1/8 Inch Hex Bore," this value would be 1.125 inches. The specific 1-1/4 inch entry in the table underscores the availability of the H7 series in various hex bore sizes, each designed to perfectly mate with corresponding hex shafts, ensuring maximal surface contact for torque transfer and minimal backlash.
• Bore Type: Hex: The hexagonal bore is a key design choice for applications requiring robust positive drive without the complexity or potential weaknesses of multiple splines or a single keyway in certain contexts. It provides excellent concentricity and a large surface area for power transmission.
• Center Line to End of Hub (in.): 2.50: This critical dimension defines the overall length of the yoke from the center of the U-joint cross to the end of the shaft-receiving hub. It is essential for determining the overall length of the driveline assembly and for ensuring proper clearance within the application's physical constraints. Accurate measurement prevents interference and ensures the U-joint operates within its designed angular limits.
• End of Hub to Centerline of Set Screw Hole (in.): 0.625: This dimension indicates how far into the hub the shaft must extend to align with the securing set screw. Proper engagement ensures the set screw bites into the shaft (often into a dimple or flat) effectively, preventing axial and rotational movement of the shaft relative to the yoke.
• Finish: Plain: A plain finish typically means the surface is as-machined or has undergone minimal surface treatment. While functionally sound, it implies that the end-user may consider additional corrosion protection (e.g., painting, coating) depending on the operating environment.
• Hub Dia (in.): 2.00: The outer diameter of the hub provides the necessary material thickness and structural integrity around the hex bore and the U-joint bearing seats. A robust hub diameter is essential for resisting torsional stresses and ensuring a long service life for the U-joint cups and bearings.
• Joint Angle: 15: This represents the maximum recommended continuous operating angle for the universal joint when connected to this yoke. Operating within this specified angle is crucial for optimizing the lifespan of the universal joint, minimizing vibration, and ensuring uniform power delivery. Exceeding this angle can lead to increased friction, heat, wear, and potential driveline imbalances.
• Keyway At: Hex / Keyway Size (in.): -: These specifications confirm that the hex bore itself serves as the 'keyway' mechanism. The hexagonal shape eliminates the need for a separate key or splines, simplifying shaft installation and reducing potential points of failure often associated with traditional key and keyway designs.
• Material: Forged Steel: Re-emphasizing its importance, forged steel provides exceptional strength, durability, and resistance to impact and fatigue, which are critical for components subjected to high dynamic loads in power transmission systems.
• Series: H7: The 'H7' designation places this yoke within a specific product line from Buyers Products, typically indicating a performance category, duty rating (medium-duty in this case), and adherence to a set of internal design and quality standards.
• Set Screw At: 4 / Set Screw Size: 3/8-16: The "4" likely refers to a clock-face position (e.g., 4 o'clock) or a specific flat on the hex bore where the set screw is located. The 3/8-16 UNC thread size specifies the dimensions and threading of the set screw, ensuring compatibility with standard tooling and providing a robust clamping force.

Advantages and Long-Term Value

Investing in the Buyers Products H7 Series End Yoke with a 1-1/8 Inch Hex Bore offers several distinct advantages for system designers and operators:

• Superior Strength and Durability: Forged steel construction ensures exceptional resilience against operational stresses, leading to a longer service life and reduced replacement frequency.
• Efficient Power Transmission: The hex bore design provides a positive, low-backlash connection, maximizing the transfer of torque from the power source to the driven component.
• Enhanced Reliability: The robust material and design minimize the risk of failure under demanding conditions, contributing to greater operational uptime and reduced maintenance costs.
• Broad Compatibility: Interchangeability with major manufacturers' components simplifies procurement and integration into diverse driveline systems.
• Optimized Performance: When coupled with compatible U-joints, the yoke facilitates smooth and continuous torque transfer across various operating angles, enhancing overall system efficiency and reducing wear on adjacent components.
• Cost-Effectiveness Over Lifecycle: While initial investment might reflect its quality, the long-term benefits of durability, reduced maintenance, and reliable performance translate into significant cost savings over the operational lifespan of the equipment.

Conclusion

The Buyers Products H7 Series End Yoke, particularly the variant featuring a 1-1/8 inch hex bore, stands as a testament to engineering excellence in power transmission components. Its forged steel construction, precise hexagonal bore, and carefully considered dimensions make it an indispensable element for medium-duty driveline systems demanding high strength, efficient torque transfer, and exceptional longevity. Designed for seamless integration with Buyers Products NB7A U-joints and compatible with other industry standards, this end yoke offers a reliable, robust, and technically superior solution for a wide range of industrial, agricultural, and commercial applications. By providing continuous, smooth torque transfer and withstanding significant operational stresses, the H7 Series End Yoke ensures the enduring performance and reliability of critical machinery, making it a pivotal choice for engineers and professionals prioritizing durability and efficiency.