Split-Type Tractor Steering Cylinder for Ningbo Axle | 487mm C-C

Split-Type Tractor Steering Cylinder for Ningbo Axle — 50 mm Bore × 130 mm Stroke Short-Travel Dual-Body Hydraulic Ram

Product Type	Split-Type (Dual Cylinder Body)
Bore Diameter	50 mm
Rod Diameter	25 mm
Stroke (per body)	130 mm
Mounting Distance (C-C)	487 mm
Axle Compatibility	Ningbo-Standard Front Axle
Cylinder Configuration	Double-Acting, Split-Mount
Seal Material	PU Primary + NBR Backup

Request Matched-Pair Pricing

Ningbo axle fitment verified · Sold in pairs · FOB Ningbo

Engineering Overview: Short-Stroke 130 mm Split-Type Tractor Steering Cylinder Variant for Narrow Ningbo Axle Track Configurations

The Split-Type Tractor Steering Cylinder for Ningbo Axle with a 130 mm stroke per body is closely related to Product 3’s 135 mm stroke Ningbo-axle variant but is dimensionally distinct in two key parameters: the stroke is 5 mm shorter per body (130 mm vs. 135 mm), and the C-C mounting distance is 8 mm shorter (487 mm vs. 495 mm). These differences, while small in absolute terms, reflect a different sub-variant of the Ningbo front axle platform—one with a slightly narrower bracket span and a reduced steering arm sweep requirement. Procurement engineers maintaining parts records for fleets containing multiple Ningbo-axle tractor variants must not treat these two cylinders as interchangeable: a 5 mm stroke difference alters the maximum wheel lock angle by a measurable amount, and an 8 mm C-C difference means the retracted cylinder either cannot reach the bracket pin bore or introduces compressive pre-load on the clevis when installed on a mismatched axle.

The 50 mm bore and 25 mm rod specification matches the Product 3 variant exactly, confirming that the Ningbo axle platform uses a common bore-and-rod standard across multiple C-C and stroke sub-variants. This standardisation simplifies seal kit inventory—a single PU seal kit covers both the 130 mm and 135 mm stroke variants—but the cylinder bodies themselves are not interchangeable due to the barrel length and C-C differences. This distinction is a common source of ordering errors in multi-machine fleet environments: a technician who successfully used Product 3 on one tractor model may incorrectly assume it fits another Ningbo-axle model in the same fleet, producing a cylinder that is 5 mm too long in the retracted position and cannot be pinned into the bracket without forcing the clevis off-centre.

Primary applications include compact two-wheel-drive tractors in the 35–55 hp range built on the narrow-bracket Ningbo axle sub-variant, distributed across South and Southeast Asian markets and increasingly in South American agricultural regions where Chinese compact tractors have established strong market penetration. The 487 mm C-C is also found on certain YTO-derived front axle variants produced under licence, so technicians encountering YTO-platform machines should measure the existing C-C before assuming Product 3 or Product 7 is the correct match.

Hydraulic Performance: Dual-Body Force Balance, Fluid Volume per Stroke, and Seal Configuration for the 50 mm × 130 mm Split-Mount Hydraulic Steering Ram

Each cylinder body has a bore area of 1,963 mm² and a rod area of 491 mm². At 12 MPa operating pressure, each body produces 23.6 kN extension and 17.7 kN retract force. The combined two-body system delivers 47.2 kN extension and 35.4 kN retract—identical to Product 3’s force output, since both share the same bore and rod specification. The hydraulic fluid volume per full stroke is 255 cm³ per body on extension (1,963 mm² × 130 mm), slightly less than the 265 cm³ of the 135 mm variant, reducing the circuit’s total flow demand marginally. For a 2.0-second lock time, the minimum required pump flow rate is approximately 7.7 L/min combined for both bodies—within the standard tractor gear pump operating range at mid-idle speed.

Barrel material is 20# seamless precision steel, bore honed to Ra ≤ 0.4 µm. The 130 mm stroke is short enough that honing taper risk is low, but batch dimensional inspection still verifies bore diameter at three axial positions using a 50 mm air plug gauge. The 25 mm rod is 45# carbon steel, induction hardened to 55–60 HRC, chrome plated to 20–25 µm, and ground to h6 tolerance. Seal kit per body: PU piston U-ring, NBR O-ring piston secondary, PU rod U-seal, and PU wiper seal. As with Product 3, both bodies within a matched pair should be re-sealed using seal kits from the same production batch to maintain consistent inter-body leakage balance and avoid asymmetric steering effort developing over time.

Fitment Verification: 487 mm C-C vs. 495 mm Distinguishing the Two Ningbo Axle Split-Type Hydraulic Power Steering Cylinder Variants

The definitive distinguishing measurement between this cylinder and the Product 3 variant is the retracted C-C distance: 487 mm here vs. 495 mm on Product 3. To measure correctly, place a digital vernier calliper between the centre of the barrel-end clevis pin and the centre of the rod-end clevis pin with the cylinder fully retracted. If the measurement is 487 ± 2 mm, this is the correct cylinder. If it is 495 ± 2 mm, Product 3 applies. Clevis pin bore diameter on this variant is 22 mm H7 at both ends, identical to Product 3. The five-parameter verification set is: 50 mm bore, 25 mm rod, 130 mm stroke, 487 mm C-C, 22 mm clevis pin. Do not rely on visual appearance alone—the external envelope of the two variants is nearly identical, and incorrect ordering based on visual matching is a documented field-support issue for distributors stocking both Ningbo-axle variants.

For distributors serving markets with mixed Ningbo-axle tractor populations, maintaining separate SKUs for the 130 mm (487 mm C-C) and 135 mm (495 mm C-C) variants—with clear dimensional labelling on the carton—is the most effective way to prevent field installation errors. Stocking 5 pairs of each variant provides coverage for the typical seasonal maintenance demand without committing excessive capital to slow-moving inventory. Both variants use the same seal kit, simplifying the aftermarket consumables inventory to a single SKU for both cylinder body sizes.

Installation, Simultaneous Replacement Protocol, and Maintenance Intervals for the 130 mm Stroke Ningbo Axle Split-Type Steering Cylinder

Replace both cylinder bodies simultaneously. Measure and record the existing C-C distance on both the left-hand and right-hand cylinder before removal to confirm both are the 487 mm variant—occasionally a previous technician may have fitted mismatched bodies from the two variants, producing a subtle steering pull that is difficult to diagnose without this measurement. Remove both cylinders, clean and inspect all bracket pin bores for ovality, and rebush any bore measuring beyond 22.15 mm before fitting the new units. Torque clevis pin retention fasteners to 35–40 N·m. Use M14×1.5 port fittings with new copper sealing washers; torque to 30–35 N·m. Bleed the circuit with five full lock-to-lock cycles at low idle. After bleeding, verify that both rods extend and retract at equal speed during the same steering input; any speed differential indicates a flow restriction or air pocket in one circuit branch. Seal inspection at 500-hour intervals; full seal kit replacement at 2,000 hours in clean conditions or 1,200 hours in high-dust environments.

Quality Control, Matched-Pair Testing, and B2B Procurement for the 50 mm × 130 mm Ningbo Axle Tractor Steering Cylinder

Factory QC follows the matched-pair protocol identical to Product 3: both bodies from a pair are tested sequentially on the same rig within the same shift, at the same fluid temperature and ambient conditions. Proof test: 21 MPa static for 5 minutes per stroke direction; 10 dynamic cycles at rated pressure. Internal leakage acceptance: ≤2 mL/min per body, with a matched-pair leakage differential of ≤0.5 mL/min between the two bodies. Chrome rod batches are subjected to 240-hour ASTM B117 salt spray testing. Export packaging is one pair per corrugated carton with VCI poly wrap and foam end-cap inserts. MOQ: 5 pairs (10 bodies). Standard pallet: 20 pairs (40 bodies). Lead time: 7–12 working days FOB Ningbo. Custom options: modified C-C in 5 mm increments for non-standard Ningbo sub-variants, BSP or NPT port threads, FKM seal upgrades. OEM white-label documentation available in English, Spanish, and Portuguese.