HH-YG45-220-V90 Combine Hydraulic Cylinder | 55mm Bore, 220mm Stroke

Model: HH-YG45_220-V90

HH-YG45_220-V90 Combine Hydraulic Cylinder

A precision-engineered combine hydraulic cylinder built for the mechanical demands of modern grain harvesting. With a 55 mm bore, 40 mm rod, and 220 mm stroke, the HH-YG45_220-V90 delivers controlled, repeatable force output in header lift and frame positioning applications where fractions of a millimetre matter to crop throughput.

Key Specifications

Bore Diameter55 mm
Rod Diameter40 mm
Stroke220 mm
Mounting Length385 mm

What the HH-YG45_220-V90 Agricultural Hydraulic Cylinder Is Designed to Do

Combine harvesters operate in conditions that would expose a mediocre hydraulic cylinder within a single season — high vibration from the threshing drum, contaminated fluid environments, and continuous duty cycles that run from sunrise to well past sunset during peak harvest. The HH-YG45_220-V90 is purpose-built for this environment, specifically for the actuation systems that control header position, reel height, and ancillary frame adjustments on mid-to-large-frame combines.

The 55 mm bore is the pivotal parameter here. At typical combine hydraulic system pressures of 140–180 bar, a 55 mm bore generates a push force in the range of 3,300–4,240 N. That’s more than sufficient to lift and hold a 15–20 ft grain header while the machine negotiates uneven field terrain without constant operator correction. The 40 mm rod diameter — a 73% rod-to-bore ratio — keeps buckling risk negligible across the full 220 mm stroke, even under lateral loading from header sway.

The V90 suffix designates the end-cap geometry and port orientation specific to this variant, ensuring that this cylinder integrates directly into OEM-compatible bracket and hose routing configurations without field modifications.

HH-YG45 220 V90 Combine Hydraulic Cylinder Specifications: Why Each Dimension Matters

Engineering data without context is just numbers. Here’s what each parameter of the HH-YG45_220-V90 means in practical combine operation:

• Bore Ø 55 mm: Sets the maximum push and pull force the cylinder can deliver. With a 55 mm piston area of approximately 23.75 cm², you get consistent lift capacity that handles header weight variation caused by mud, crop build-up, or wet straw loading — conditions common in late-season rice or wheat harvest.
• Rod Ø 40 mm: A larger-diameter rod increases column strength under compressive loading. In a header cylinder context, this matters during folding operations and when headers are locked in transport position — the rod must withstand sustained axial load without deflection.
• Stroke 220 mm: Dictates the range of header height adjustment available to the operator. 220 mm of travel maps precisely to the geometry of several major combine platforms, giving full bottom-to-top header travel without cylinder over-extension or dead-zone positioning.
• Mounting Length 385 mm (C–C): Pin-to-pin dimension. This closed-position mounting length is critical for matching the factory bracket geometry — deviating by even 5–10 mm would require bracket modification or introduce articulation angles that accelerate seal wear.

All four dimensions work together as a system. Altering any one of them changes the force delivery, the travel envelope, or the mechanical compatibility — which is why OEM-matched specifications like the HH-YG45_220-V90 exist as distinct part numbers rather than generic agricultural hydraulic cylinders.

Construction and Sealing: Built for Long-Season Field Reliability

The barrel of the HH-YG45_220-V90 is produced from precision-honed seamless tubing with a bore surface roughness of Ra ≤ 0.4 µm — the finish specification required for polyurethane and NBR piston seals to achieve full hydrodynamic lubrication without micro-stick-slip during slow controlled movements. Header auto-levelling systems, which make constant small corrections at low velocity, are particularly sensitive to this: a rough bore surface causes jerky response that the operator feels as hunting behaviour.

The chrome-plated piston rod achieves a minimum chrome thickness of 25 µm with a hardness of 850–1000 HV. In field conditions, rod surfaces contact airborne abrasive dust (typical in cereal grain harvest) and occasional droplet impingement from spray nozzles on self-propelled sprayers working adjacent rows. The hard chrome layer resists this abrasive wear cycle, protecting the rod wiper seal from premature failure — the most common point of leakage in combine cylinders used in sandy or silty soils.

End caps are machined from ductile iron or carbon steel, with port threads conforming to BSP or ORFS standards depending on the specific machine platform. Clevis and pin bore dimensions are machined to H7 tolerance, ensuring a fit that prevents bush slap and the fretting corrosion that causes bracket wear on high-cycle cylinders.

Compatible Applications and Replacement Scenarios for Harvest Cylinder Sourcing

The HH-YG45_220-V90 is designed as a direct-fit replacement or OEM-equivalent cylinder for combine platforms that share the 55/40/220/385 dimension set. Typical replacement scenarios include:

• End-of-season rebuild programmes — replacing cylinders with known mileage before the next harvest to avoid in-field failures during critical windows.
• Seal failure after contaminated fluid ingress — when a ruptured return filter allows particulate above 25 µm to reach cylinder seals, replacement is more economical than re-sealing in the field.
• Aftermarket parts sourcing — for fleet operators running multiple machines who need consistent specifications across their inventory rather than mixing OEM part numbers.
• Custom machine builds — agricultural machinery fabricators building combine attachments or header trailers who need a proven cylinder with a documented dimensional standard.

If you are uncertain whether this cylinder matches your combine platform, we can cross-reference against your machine model number, existing cylinder part number, or dimensional measurements taken from the installed cylinder.

Complete Technical Specifications