H2136203 - Hydraulic Gear Pump With 1 Inch Keyed Shaft And 2 Inch Diameter Gear

The H21 Series Hydraulic Gear Pump with Keyed Shaft from Buyers Products is a sturdy, durable bi-rotational pump that can be 2- or 4-bolt mounted in an SAE B mount. The pump is built tough of cast iron with Teflon-coated bronze thrust plates. Four internal dowels work to protect its structural integrity. Its input shaft is supported by a heavy duty bearing. Choose from a range of models with flow rates from 11.3 to 15.3 at 1000 RPM. The pumps are capable of higher pressures, taking up to 2500 or 3000 PSI. All of the models feature a 1 in. keyed shaft.

Specifications

Advanced Technical Overview: H21 Series Hydraulic Gear Pump with 1-Inch Keyed Shaft and 2-Inch Diameter Gear

The H21 Series Hydraulic Gear Pump, engineered and manufactured by Buyers Products, represents a pinnacle in robust fluid power solutions for demanding mobile and industrial hydraulic applications. This detailed technical description aims to elucidate the fundamental design principles, material science, performance characteristics, and application suitability of this exceptional component. With a specific focus on the model featuring a 1-inch keyed shaft and a 2-inch diameter gear, we will explore the engineering choices that contribute to its reliability, efficiency, and longevity under arduous operating conditions.

Precision Engineering and Durable Construction

At the core of the H21 Series pump's superior performance is its meticulously engineered construction. The main housing is fabricated from high-grade cast iron, a material renowned in hydraulic component manufacturing for its exceptional strength-to-weight ratio, superior vibration damping capabilities, and excellent resistance to thermal distortion. This inherent rigidity of cast iron is critical for maintaining precise internal clearances between the rotating gears and the pump housing, even when subjected to the high internal pressures characteristic of hydraulic systems. Such dimensional stability ensures consistent volumetric efficiency and mitigates the risk of accelerated wear, thereby extending the operational lifespan of the pump.

Further enhancing its durability, the H21 Series incorporates Teflon-coated bronze thrust plates. These specialized thrust plates serve a dual function. Firstly, the bronze substrate provides a robust, wear-resistant surface that can withstand the axial forces exerted by the gears. Secondly, the Teflon coating significantly reduces the coefficient of friction, minimizing energy losses due to friction and preventing metal-on-metal contact. This innovative combination ensures optimal lubrication, even in boundary lubrication conditions, and drastically reduces internal leakage paths around the gear faces. The result is improved volumetric efficiency, reduced heat generation, and enhanced overall pump performance and longevity.

To bolster the structural integrity of the pump assembly, four internal dowels are strategically positioned. These precision-machined dowels play a crucial role in maintaining the accurate alignment of the pump's internal components, including the gear housing and end plates. By preventing relative movement and ensuring concentricity, these dowels safeguard the critical tolerances essential for efficient gear meshing and minimal internal slippage. This design feature is paramount in preventing deformation under transient pressure spikes and sustained high-pressure operation, thereby preserving the pump's performance characteristics over an extended service life.

Optimized Power Transmission: Shaft and Bearing System

Power transmission from the prime mover to the hydraulic fluid is facilitated by a robust 1-inch keyed input shaft. The keyed shaft design is a time-tested and universally recognized method for ensuring a positive, non-slip mechanical connection for torque transfer. The keyway, precision-machined into the shaft, accommodates a corresponding key within the drive coupling, effectively transmitting rotational force without slippage. The 1-inch diameter provides ample cross-sectional area to withstand the torsional stresses associated with high-torque hydraulic applications, ensuring reliable and efficient power transfer from the engine, electric motor, or PTO to the pump's internal gears.

Supporting this critical input shaft is a heavy-duty bearing system. The selection of an appropriately robust bearing is paramount for managing the complex interplay of radial and axial loads that the shaft experiences during operation. Radial loads arise from the pressure differential across the gears and the reaction forces from the drive coupling, while axial loads can originate from shaft sealing arrangements or external mounting stresses. The heavy-duty bearing utilized in the H21 Series is engineered to absorb these forces effectively, maintaining precise shaft alignment, minimizing deflection, and ensuring smooth, low-friction rotation. This significantly contributes to the pump's mechanical efficiency, reduces wear on adjacent components, and extends the overall operational life by preventing premature failure due to fatigue or excessive wear.

Gear Geometry, Displacement, and Flow Characteristics

The heart of this hydraulic gear pump lies in its precision-machined 2-inch diameter gears with a 2.000-inch width. These dimensions are crucial determinants of the pump's positive displacement characteristic. In an external gear pump, fluid is drawn into the inlet chamber, trapped between the gear teeth and the pump casing, and then carried around to the outlet port where it is forced out as the teeth mesh. The volumetric displacement of the pump, specified at 4 cubic inches per revolution, is a direct function of the gear geometry – specifically, the number of teeth, pitch diameter, and gear width. A displacement of 4 cubic inches per revolution translates into substantial fluid delivery per rotation, making this pump suitable for applications requiring significant hydraulic power.

The volumetric flow rates are a critical performance metric, directly correlating with the rotational speed (RPM) of the input shaft and the pump's displacement. The H21 Series offers a range of models, with the featured unit demonstrating a flow rate of 15 gallons per minute (GPM) at 1000 RPM. This performance is linearly scalable with RPM, as evidenced by the provided specifications:

• At 600 RPM: 9.0 GPM
• At 900 RPM: 13.5 GPM
• At 1000 RPM: 15 GPM
• At 1200 RPM: 18.36 GPM
• At 1500 RPM: 22.5 GPM
• At 1800 RPM: 27.0 GPM
• At 2100 RPM: 31.5 GPM

These figures illustrate the pump's consistent and predictable flow output across its operational speed range, up to a maximum recommended RPM of 2000. This linearity is a hallmark of well-designed positive displacement pumps, allowing for precise control over hydraulic actuator speed and system response. The capability to deliver substantial flow at moderate RPMs ensures efficient operation and minimizes power losses, making it an ideal choice for a wide array of mobile and industrial hydraulic systems.

Pressure Capability and Bi-Directional Functionality

The H21 Series pump is engineered for high-pressure hydraulic applications, capable of operating at a maximum continuous pressure of 2500 PSI, with some models extending to 3000 PSI. This high-pressure rating is a testament to the robust construction, precise internal tolerances, and superior material selection, particularly the cast iron housing and strong gear teeth. Operating at elevated pressures demands exceptional structural integrity to prevent housing distortion and internal leakage, ensuring that the delivered fluid power is effectively converted into useful work. This pressure capability makes the pump suitable for tasks involving heavy lifting, clamping, pressing, and other high-force hydraulic operations.

A notable feature of the H21 Series is its bi-directional rotation capability. Unlike uni-directional pumps that are restricted to a single direction of rotation (either clockwise or counter-clockwise), the H21 Series can be driven in either direction without internal modification. This versatility simplifies system design, inventory management, and installation. It eliminates the need for separate pump models for different rotational requirements and provides greater flexibility in integrating the pump with various prime movers and power take-off (PTO) configurations. The bi-directional design is achieved through symmetrical internal porting and sealing arrangements that accommodate fluid flow regardless of the gear rotation direction.

Mounting Versatility and Porting Configurations

Adaptability to diverse installation requirements is a key attribute of the H21 Series. The pump features an SAE B 2/4 bolt mount type, complete with a 4.00-inch pilot diameter. The SAE B standard is a widely recognized industrial standard for hydraulic pump mounting, ensuring compatibility with a broad range of drive components and power take-off units. The availability of both 2-bolt and 4-bolt patterns offers maximum flexibility for secure attachment, accommodating various mounting plates and ensuring stable installation even in environments with significant vibration or dynamic loads.

The option for both direct mount and remote mount configurations, supported by an integral bracket input mount type, further enhances its versatility. Direct mounting minimizes the number of components and reduces potential alignment issues, providing a compact and efficient power unit. Remote mounting, on the other hand, allows the pump to be positioned away from the prime mover, which can be advantageous in terms of space constraints, noise reduction, or maintenance accessibility. This adaptability ensures seamless integration into a wide array of existing and new hydraulic systems.

Efficient fluid transfer is facilitated by thoughtfully designed porting. The pump features a 1 1/4 NPT inlet port size and a 1 1/4 NPT outlet port size, with an additional 1 NPT rear port size, offering both rear and side porting options. National Pipe Taper (NPT) threads are standard in North American hydraulic systems, providing robust and leak-resistant connections when properly sealed. The generous 1 1/4 NPT sizing for both inlet and outlet ports is crucial for minimizing pressure drop, reducing fluid velocity, and mitigating the risk of cavitation at the inlet, particularly important when handling high flow rates. The availability of multiple port locations (rear/side) provides system designers with optimal routing flexibility for hydraulic lines, accommodating various spatial and layout constraints and ensuring efficient connection to the hydraulic reservoir and system actuators.

Applications and Industry Suitability

Given its robust construction, high-pressure capability, and versatile performance characteristics, the H21 Series Hydraulic Gear Pump is exceptionally well-suited for a broad spectrum of demanding applications across multiple industries. Its ability to deliver consistent flow at high pressures makes it an ideal choice for:

• Mobile Hydraulics: Including dump trucks, refuse compactors, snowplows, salt spreaders, utility vehicles, wreckers, and agricultural machinery such as tractors and combines, where reliable power for lifting, pushing, and actuating implements is essential.
• Construction Equipment: Small to medium-sized excavators, skid-steer loaders, trenchers, and other machinery requiring precise and powerful hydraulic functions.
• Material Handling: Forklifts, lift gates, and conveyor systems that demand robust and consistent hydraulic power for lifting and moving heavy loads.
• Industrial Power Units: Supplying hydraulic power for a variety of fixed industrial applications, including presses, machine tools, and automation systems where reliability and durability are paramount.

The bi-directional nature and flexible mounting options further enhance its appeal for OEM and aftermarket installations, providing a single solution for varied rotational inputs and integration challenges.

Maintenance and Longevity Considerations

The design of the H21 Series Hydraulic Gear Pump emphasizes low maintenance and long service life. The inherent wear resistance of cast iron, coupled with the friction-reducing properties of Teflon-coated bronze thrust plates and the durability of the heavy-duty bearing, ensures sustained performance over extended operating periods. Regular maintenance, such as ensuring clean hydraulic fluid and proper system filtration, remains critical to maximizing the pump's lifespan. Hydraulic fluid acts as both a power transmission medium and a lubricant, and its quality directly impacts the wear rate of internal components. Adherence to recommended fluid specifications and filtration standards will preserve the precision internal tolerances and prevent premature failure due to contamination-induced wear.

Conclusion

The H21 Series Hydraulic Gear Pump with a 1-inch keyed shaft and 2-inch diameter gear from Buyers Products stands as a testament to engineering excellence in hydraulic fluid power. Its robust cast iron construction, augmented by Teflon-coated bronze thrust plates and precision doweling, ensures exceptional durability and structural integrity. The heavy-duty bearing supporting the 1-inch keyed shaft guarantees efficient and reliable power transmission. With a 4 cubic inch displacement, consistent flow rates up to 31.5 GPM at 2100 RPM, and a maximum pressure capability of 2500 PSI, this bi-directional pump offers outstanding performance. Coupled with its versatile SAE B 2/4 bolt mounting and multi-port options, the H21 Series is an indispensable component for a wide array of demanding mobile and industrial hydraulic applications, promising reliability, efficiency, and prolonged operational life.