<\/p>\n
YM4P.83.04b \u00b7 Corn Harvester Series<\/p>\n
4-Row Corn Hopper Dump Cylinder<\/h2>\n
Mid-stroke, high-force tipping actuator for grain hopper discharge on 4-row self-propelled corn harvesters \u2014 engineered for controlled, full-load dump cycles under continuous seasonal use.<\/p>\n
\nRod 40 mm<\/span>
\nStroke 695 mm<\/span>
\nC\/C 1200 mm<\/span>
\nPart No. YM4P.83.04b<\/span><\/div>\n<\/div>\n
![\"YM4P.83.04b](\"https:\/\/ever-powers.com\/wp-content\/uploads\/2026\/08\/YM4P.83.04b-4-Row-Corn-Hopper-Dump-Cylinder.webp\" "\\"\\"")
<\/div>\n<\/div>\n<\/p>\n
Full Specification at a Glance<\/p>\n
Bore Diameter<\/p>\n
63 mm<\/span><\/p>\n Push force \u2248 49.8 kN @ 160 bar \u2014 full-load dump capable<\/p>\n<\/div>\n Rod Diameter<\/p>\n 40 mm<\/span><\/p>\n Euler buckling SF 3.1:1 at full 695 mm extension<\/p>\n<\/div>\n Stroke<\/p>\n 695 mm<\/span><\/p>\n Full hopper tilt angle \u2014 typically 45\u201355\u00b0 pivot arc on 4-row platforms<\/p>\n<\/div>\n Mounting Distance<\/p>\n 1200 mm<\/span><\/p>\n C\/C retracted. Extended C\/C: 1895 mm.<\/p>\n<\/div>\n Rated Pressure<\/p>\n 160 bar<\/span><\/p>\n Continuous working pressure \u2014 standard ag circuit<\/p>\n<\/div>\n Surge Pressure<\/p>\n 210 bar<\/span><\/p>\n End-of-stroke impact rating \u2014 proof tested per unit<\/p>\n<\/div>\n Rod Chrome<\/p>\n 25\u201330 \u00b5m<\/span><\/p>\n Hard chrome HV 800+, eddy-current verified full length<\/p>\n<\/div>\n Oil Volume (extend)<\/p>\n 2.17 L<\/span><\/p>\n At 20 L\/min circuit flow \u2014 full dump completes in \u2248 6.5 s<\/p>\n<\/div>\n Seal System<\/p>\n PU Quad-ring \u221225 \u00b0C to +100 \u00b0C, mineral oil & HETG compatible<\/p>\n<\/div>\n Mounting Style<\/p>\n Clevis \u00d7 2<\/p>\n \u00d825 mm pin bore both ends, sintered bronze bush<\/p>\n<\/div>\n<\/div>\n <\/p>\n Push Force (Tip)<\/p>\n 49.8 kN<\/p>\n F = 160 bar \u00d7 \u03c0\/4 \u00d7 63\u00b2<\/p>\n<\/div>\n Pull Force (Return)<\/p>\n 29.7 kN<\/p>\n F = 160 bar \u00d7 \u03c0\/4 \u00d7 (63\u00b2\u221240\u00b2)<\/p>\n<\/div>\n Buckling SF<\/p>\n 3.1 : 1<\/p>\n F_cr \u2248 154 kN vs 49.8 kN push \u2014 comfortably above ISO 6020\/2 minimum 2.5:1<\/p>\n<\/div>\n Full Dump Cycle<\/p>\n \u2248 13 s<\/p>\n Extend + retract at 20 L\/min circuit flow \u2014 matched to operator unloading workflow<\/p>\n<\/div>\n<\/div>\n <\/p>\n The YM4P.83.04b corn hopper dump cylinder<\/strong> controls the most visually dramatic and mechanically loaded movement in the harvest cycle: tipping a grain hopper loaded with up to 800\u20131,200 kg of shelled corn through a 45\u201355\u00b0 arc to discharge into a waiting trailer or pit. It happens dozens to hundreds of times per season, always under full load, always in a timeframe the operator expects to be fast, and always with the full weight of the grain working against \u2014 then with \u2014 the cylinder as the hopper passes through its tipping axis.<\/p>\n This is not a positioning cylinder. It is a power-stroke actuator where force, speed, and end-of-stroke control determine both cycle efficiency and structural longevity of the entire hopper pivot system. The 63 mm bore, 40 mm rod, 695 mm stroke specification is the product of calculating the force-moment curve across the full tipping arc and selecting a cylinder that keeps system pressure below 140 bar at the worst-case geometry \u2014 the first 30\u00b0 of tip where the moment arm is shortest and the required cylinder force is highest.<\/p>\n <\/p>\n Every hopper dump cycle places the full grain load moment on the cylinder \u2014 force and geometry must be correctly matched across the entire tipping arc<\/p>\n<\/div>\n <\/p>\n <\/p>\n Why does the required cylinder force change as the hopper tips \u2014 and how does the 63mm bore address this?<\/p>\n A hopper dump mechanism is a rotating lever, not a linear slide. The cylinder force required to tip the hopper is determined by the moment equation: F_cyl \u00d7 L_cyl_arm = M_load \u00d7 L_load_arm. Both moment arms change continuously as the hopper rotates through its arc, and they do not change in proportion to each other. On a 4-row platform, the geometry typically produces a worst case at approximately 20\u201330\u00b0 of tilt \u2014 early in the dump \u2014 where the load moment arm is long but the cylinder moment arm is still short. This is the peak force point, and it is what sizes the bore.<\/p>\n For a 1,000 kg hopper load with a 0.6 m load moment arm at worst-case geometry, the required tip force approaches 44 kN. The 63 mm bore at 160 bar delivers 49.8 kN \u2014 providing an 13% force margin above the worst-case geometry point without requiring circuit pressure above the standard 160 bar working limit. A 56 mm bore would produce only 39.4 kN, requiring either a pressure increase to 175\u2013180 bar or accepting that the system will stall on a heavily loaded hopper at the worst-case geometry. Neither outcome is acceptable in production.<\/p>\n<\/div>\n<\/div>\n <\/p>\n The hopper passes through its tipping axis during discharge \u2014 what happens to the cylinder load at that point?<\/p>\n This is the most mechanically interesting moment in the dump cycle, and the one most often overlooked in cylinder selection. Once the hopper centre of gravity crosses the pivot axis \u2014 typically at 50\u201360\u00b0 of tilt \u2014 the load reverses: the hopper now wants to continue tipping under gravity, and the cylinder transitions from a pushing actuator to a restraining actuator. The retract side of the circuit (rod side, 29.7 kN capacity) must now control the rate of descent as the grain slides out and the empty hopper returns. If the retract force is insufficient, or if the circuit relief valve on the rod side is incorrectly set, the hopper will snap to full extension uncontrolled \u2014 a structural shock event that damages both the cylinder mount and the hopper pivot bearings.<\/p>\n The 63\/40 geometry gives 29.7 kN retract capacity \u2014 adequate to control the return of an empty hopper (typically 150\u2013250 kg) at any descent rate achievable within the circuit flow rate. Machines that have had the original cylinder replaced with a thinner-rod substitute commonly show accelerated wear at the hopper pivot pin and bracket \u2014 the consequence of under-controlled return cycles.<\/p>\n<\/div>\n<\/div>\n <\/p>\n Why is end-of-stroke cushioning relevant on a hopper dump cylinder, when most agricultural cylinders run without it?<\/p>\n On a short-stroke engagement or chopper cylinder, the kinetic energy at end-of-stroke is low \u2014 the piston mass is small and the stroke is short. On a 695 mm stroke cylinder moving a 63 mm piston at a flow-rate-limited velocity of approximately 107 mm\/s (at 20 L\/min), the kinetic energy of the moving assembly at end-of-stroke approaches a level where a hard stop generates a pressure spike in the 80\u2013120 bar range above circuit pressure. Repeated over hundreds of dump cycles per season, this compressive fatigue at the piston-end-cap contact face is a known failure initiator in dump-duty cylinders.<\/p>\n The YM4P.83.04b is available with an adjustable bore-side end-of-stroke cushion as a factory option \u2014 a tapered spear on the piston that progressively throttles return oil over the last 30\u201340 mm of stroke, decelerating the piston before contact. For OEM integrators specifying this cylinder on new platform builds, the cushion option is recommended wherever the full-extend position is a hard mechanical stop rather than a load-controlled resting position.<\/p>\n<\/div>\n<\/div>\n <\/p>\n How does the dump cylinder’s contamination environment differ from other cylinders on the same machine?<\/p>\n The hopper dump cylinder operates in a uniquely challenging contamination zone. During the dump cycle, shelled corn, husks, and fine starch dust are actively airborne around the cylinder position. More critically, the return stroke retracts a rod that may have grain dust adhered to it from the dump phase \u2014 a fine, mildly hygroscopic particulate that packs into the wiper seal gap and, over repeated cycles, acts as a mild abrasive against the chrome rod surface.<\/p>\n The dual-lip wiper fitted to this cylinder \u2014 an outer polyurethane scraper lip plus a secondary exclusion lip \u2014 is specifically designed to handle particulate contamination during retract. The outer lip removes bulk material; the secondary lip maintains a film of hydraulic oil on the rod surface during the final 10 mm of retract, providing lubrication for the inner rod seal rather than allowing the rod to enter the seal contact dry. This is not standard on all cylinder designs and is a meaningful durability differentiator in this application.<\/p>\n<\/div>\n<\/div>\n <\/p>\n Cylinder Tube<\/p>\n E355 cold-drawn seamless, 63 mm bore \u00d7 9 mm wall. Honed Ra \u2264 0.4 \u00b5m. External finish: zinc phosphate + PU topcoat, 80 \u00b5m DFT minimum, 500-hour salt spray tested.<\/p>\n<\/div>\n Chromstange<\/p>\n Ck45 steel, ground Ra \u2264 0.2 \u00b5m. Hard chrome 25\u201330 \u00b5m, HV 800+. Post-chrome ground h6. At 695 mm stroke, rod straightness verified \u2264 0.2 mm total \u2014 rejects above this threshold before chrome.<\/p>\n<\/div>\n Wiper \/ Seal Pack<\/p>\n Dual-lip PU wiper (outer scraper + secondary film-retention lip). Inner: dual-lip PU rod seal. Piston: quad-ring PU primary + PTFE backup. Full seal kit catalogued as separate spare.<\/p>\n<\/div>\n End Fixings<\/p>\n Clevis both ends, \u00d825 mm pin bore, sintered bronze self-lubricating bush, grease nipple. Clevis wall 15 mm machined steel. Cushion option: adjustable tapered spear, bore-side, factory-fit.<\/p>\n<\/div>\n QC Protocol<\/p>\n Hydrostatic proof 210 bar \u00d7 60 s per unit. Full-stroke \u00d7 5 cycles under rated load. External leakage check both ports. Dimensional audit: C\/C, stroke, pin bore. Batch records available to OEM.<\/p>\n<\/div>\n<\/div>\n <\/p>\n A full hopper dump at peak harvest \u2014 the cylinder manages the entire load moment from first tilt to empty return, every cycle<\/p>\n<\/div>\n <\/p>\n Procurement teams sourcing this cylinder for a service network should understand the actual cycle loading it faces over a season. On a 4-row self-propelled corn harvester operating at typical field capacity, the hopper fills in 15\u201325 minutes of harvesting. Over a 10\u201312 hour harvest day, the operator performs 25\u201340 full dump cycles. Across a 30-day harvest season, this totals 750\u20131,200 full extend-retract cycles, every one under full grain load on extension and controlled empty-hopper return on retraction.<\/p>\n Cycles per Season<\/p>\n 750\u20131,200<\/p>\n Full load extend + controlled retract. Seal design validated to 5,000 cycles minimum in laboratory endurance testing.<\/p>\n<\/div>\n Recommended Inspection<\/p>\n End of season<\/p>\n Check rod chrome, inspect wiper for corn-dust compaction, grease pin bushes. Replace seal kit if any weeping present.<\/p>\n<\/div>\n Seal Kit Lead Time<\/p>\n < 5 days<\/p>\n Seal kit stocked and catalogued separately. Field replacement time \u2248 60 min with standard C-spanner tooling.<\/p>\n<\/div>\n Pin Bush Service<\/p>\n 2\u20133 seasons<\/p>\n Sintered bronze self-lubricating. Replace when radial play exceeds 0.8 mm \u2014 excessive pin play accelerates rod scoring.<\/p>\n<\/div>\n<\/div>\n <\/p>\n Standard YM4P.83.04b ships from stock. Integrators developing proprietary hopper systems can modify the following parameters without tooling surcharge at qualifying volumes:<\/p>\n All custom configurations supplied with 2D dimensional drawing, Euler buckling safety factor report, and STEP file on request \u2014 before production confirmation. Standard lead time 7\u201315 business days ex-works; custom 20\u201335 business days depending on volume and specification.<\/p>\n <\/p>\n Ready to Source or Specify?<\/p>\n Request Drawings, Buckling Report, OEM Pricing, or Custom Dump Cylinder Engineering<\/p>\n Hopper dump cylinders carry full grain load on every cycle. Our technical team provides force-moment curve analysis, Euler buckling calculations, 2D\/3D drawings, and material certifications \u2014 standard for all OEM and distribution enquiries on this product.<\/p>\n
\n+ PTFE guide<\/span><\/p>\n![\"4-row](\"https:\/\/ever-powers.com\/wp-content\/uploads\/2026\/08\/Corn-harvester.webp\" "\\"\\"")
<\/p>\n4-Row Corn Hopper Dump Cylinder 63mm Bore 695mm Stroke \u2014 The Engineering Behind Every Tipping Cycle<\/h2>\n
Combine Harvester Hopper Actuator OEM Construction \u2014 Materials and Process Standards<\/h2>\n
![\"Corn](\"https:\/\/ever-powers.com\/wp-content\/uploads\/2026\/08\/Corn.webp\" "\\"\\"")
<\/p>\nHydraulic Cylinder for Corn Harvester Grain Hopper Tipping \u2014 Service Life Under Realistic Seasonal Load<\/h2>\n
Combine Harvester Hopper Unloading Cylinder \u2014 OEM Custom Configurations and Batch Supply<\/h2>\n
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