{"id":1757,"date":"2026-09-08T03:59:06","date_gmt":"2026-09-08T03:59:06","guid":{"rendered":"https:\/\/ever-powers.com\/?post_type=product&p=1757"},"modified":"2026-09-08T04:00:09","modified_gmt":"2026-09-08T04:00:09","slug":"hcyy11112027-crane-rear-outrigger-support-hydraulic-cylinder","status":"publish","type":"product","link":"https:\/\/ever-powers.com\/fr\/product\/hcyy11112027-crane-rear-outrigger-support-hydraulic-cylinder\/","title":{"rendered":"HCYY11112027 Crane Rear Outrigger Support Hydraulic Cylinder \u2014 \u03a670\u00d7\u03a655\u00d7420 | 20 MPa"},"content":{"rendered":"
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SEO Keyword Strategy \u2014 HCYY11112027<\/h2>\n

Core Keyword:<\/strong> crane rear outrigger support hydraulic cylinder<\/p>\n

Related Keywords:<\/strong> rear outrigger jack cylinder for crane \u00b7 truck crane rear stabilizer cylinder \u00b7 hydraulic rear outrigger support actuator \u00b7 crane rear leg cylinder replacement<\/p>\n

Long-Tail Keywords:<\/strong> crane rear outrigger support hydraulic cylinder replacement \u00b7 truck crane rear stabilizer jack cylinder bore and stroke verification \u00b7 compact hydraulic rear jack cylinder for mobile crane leveling<\/p>\n<\/div>\n

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HCYY11112027 \u2014 Crane Rear Outrigger Support Hydraulic Cylinder for Rear Chassis Vertical Stabilization<\/h2>\n

The HCYY11112027 crane rear outrigger support hydraulic cylinder<\/strong> is a compact vertical jack actuator that completes the truck crane’s four-point ground contact stabilization system at the rear outrigger positions. With a 70 mm bore, a 55 mm piston rod, a 420 mm stroke, and a working pressure of 20 MPa, this cylinder extends downward from the end of the deployed rear outrigger beam to drive the outrigger foot pad into contact with the ground, transferring the crane’s rear reaction load safely into the supporting surface and holding the rear of the crane chassis firmly in its leveled position throughout every lifting operation.<\/p>\n

The HCYY11112027 is the final cylinder in this crane’s seven-piece hydraulic cylinder system, and its role completes the picture of how a truck crane establishes its operating platform. Without correct rear outrigger support, the crane cannot be leveled, cannot transfer its full operating weight from its road axles to the four outrigger contact points, and cannot operate to the load chart values that govern its safe lifting capacity. Engineers, maintenance managers, and procurement buyers evaluating this cylinder must approach it as a primary structural safety component of the crane \u2014 compact in geometry, but critical in function \u2014 and must apply the same dimensional verification discipline as would be applied to any larger structural cylinder in the same machine.<\/p>\n

Buyers should also note the distinct differences between the HCYY11112027 rear support cylinder and the HCYY11112026 rear extension cylinder reviewed on the preceding product page. These two cylinders share the same rear chassis location but perform opposite functions \u2014 the extension cylinder slides the beam horizontally into position, while the support cylinder extends vertically to bear load. They differ in bore, rod diameter, stroke, installation distance, working pressure, and weight, and must not be confused or interchanged during replacement procurement.<\/p>\n

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\"HCYY11112027<\/div>\n

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Compact Hydraulic Rear Jack Cylinder for Mobile Crane Leveling \u2014 Structural Role and Rear Load Distribution<\/h2>\n

In the crane’s outrigger deployment sequence, the HCYY11112027 acts after the rear extension cylinder (HCYY11112026) has positioned the rear outrigger beam at its working width. With the rear beam extended, the rear support cylinder extends vertically downward from its housing at the beam end, driving the outrigger pad to the ground and progressively unloading the crane’s rear road axles. When all four outrigger support cylinders \u2014 two front, two rear \u2014 have extended to their required positions and the crane has been leveled, the machine stands on its four outrigger pads, ready for lifting operations.<\/p>\n

The rear outrigger support cylinders carry a share of the crane’s total vertical reaction load that is determined by the crane’s weight distribution, the load being lifted, the lift radius, and the boom slewing angle. Unlike the front outrigger support cylinders, which tend to carry a larger share of the reaction load when the boom is pointing forward, the rear outrigger support cylinders carry proportionally more load when the crane is lifting to the rear \u2014 at slewing angles where the boom points toward or over the rear of the crane chassis. In long-radius lifting configurations \u2014 where the boom is extended to near its maximum reach and the load radius is at its greatest \u2014 the dynamic load on the rear outrigger support cylinders can be particularly significant, as the crane’s center of gravity shifts toward the rear of its tipping plane.<\/p>\n

This geometry explains why the HCYY11112027, despite its compact 420 mm stroke and relatively modest 70 mm bore, must be treated as a structurally important component. The short stroke reflects the rear chassis geometry \u2014 the rear of many truck crane chassis sits closer to the ground than the front, and the vertical travel required to unload the rear axles and accommodate rear site slope is shorter than at the front. The 70 mm bore and 20 MPa working pressure are sized to generate sufficient support force for the rear outrigger load share at this hydraulic pressure level. Each parameter is a deliberate engineering choice, not a default.<\/p>\n

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\"HCYY11112027<\/div>\n

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Truck Crane Rear Stabilizer Jack Cylinder Bore and Stroke Verification \u2014 Technical Specifications<\/h2>\n

The following specifications are the authoritative engineering data for the HCYY11112027. All parameters must be verified against the original crane OEM drawing and the measured existing cylinder before any replacement or production decision is finalized.<\/p>\n

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Cylinder Bore<\/p>\n

\u03a670 mm<\/p>\n

Piston bore \u2014 determines vertical support force at rear outrigger points; larger than the rear extension cylinder, sized for load-bearing duty<\/p>\n<\/div>\n

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Piston Rod Diameter<\/p>\n

\u03a655 mm<\/p>\n

Rod-to-bore ratio approximately 78.6% \u2014 robust rod for compressive vertical load stability over the 420mm stroke<\/p>\n<\/div>\n

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Stroke<\/p>\n

420 mm<\/p>\n

Compact vertical extension range \u2014 the shortest support stroke in this crane’s outrigger system, reflecting the rear chassis geometry<\/p>\n<\/div>\n

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Installation Distance<\/p>\n

640 mm<\/p>\n

Retracted pin-to-pin reference \u2014 must match the rear outrigger beam end housing mounting geometry precisely<\/p>\n<\/div>\n

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Working Pressure<\/p>\n

20 MPa<\/p>\n

Normal continuous operating pressure for the rear support circuit \u2014 between the extension circuit (12 MPa) and the main support circuit (30 MPa)<\/p>\n<\/div>\n

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Max. Withstand Pressure<\/p>\n

30 MPa<\/p>\n

Peak structural limit \u2014 1.5\u00d7 the working pressure; not the recommended continuous operating pressure<\/p>\n<\/div>\n

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Cylinder Weight<\/p>\n

24 kg<\/p>\n

Compact and manageable for field replacement with appropriate hydraulic safety precautions observed<\/p>\n<\/div>\n

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Specification Format<\/p>\n

\u03a670 \u00d7 \u03a655 \u00d7 420<\/p>\n

Bore \u00d7 Rod Diameter \u00d7 Stroke (mm)<\/p>\n<\/div>\n<\/div>\n

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\"HCYY11112027<\/div>\n

Fig. 1 \u2014 CAD dimensional drawing for HCYY11112027. All replacement orders must be verified against the original crane OEM engineering drawing and the measured existing cylinder before production is authorized.<\/p>\n

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Engineering Analysis \u2014 Compact Hydraulic Rear Jack Cylinder for Mobile Crane Leveling and Rear Load Bearing<\/h2>\n

The HCYY11112027 occupies a unique position within the crane’s seven-cylinder hydraulic system. It is the most compact of the four outrigger support cylinders, with the shortest stroke in the support cylinder sub-group, yet it operates at a working pressure that is intermediate between the extension circuit (12 MPa) and the main outrigger support circuit (30 MPa). Each parameter reflects specific engineering choices for the rear support position, and each carries a direct consequence for replacement selection.<\/p>\n

Bore: 70 mm \u2014 Rear Outrigger Vertical Support Force<\/h3>\n

At 20 MPa working pressure, the theoretical extension force generated by the 70 mm bore is:<\/p>\n

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Effective piston area (A):<\/strong><\/p>\n

A = \u03c0 \u00d7 (0.070 m)\u00b2 \/ 4 = \u03c0 \u00d7 0.0049 \/ 4 \u2248 0.003848 m\u00b2<\/p>\n

Theoretical extension force (F) at working pressure (20 MPa):<\/strong><\/p>\n

F = 20,000,000 Pa \u00d7 0.003848 m\u00b2 \u2248 76.9 kN (approximately 7.8 tonnes-force)<\/strong><\/p>\n

This is a theoretical hydraulic force only. Actual effective support force is lower due to seal friction, hydraulic losses, and system pressure drop under dynamic operating conditions. The actual rear outrigger reaction load at any given moment depends on the crane’s load weight, lift radius, slewing angle, and dynamic factors including load swing and slewing inertia.<\/p>\n<\/div>\n

Approximately 76.9 kN of theoretical support force per rear outrigger position is the hydraulic force budget available to hold the rear of the crane chassis elevated and level under the rear outrigger’s share of the total operating load. Comparing this with the other support cylinders in the system reveals the designed load distribution: the main outrigger support cylinder (HCY11112023) generates approximately 461.8 kN at 30 MPa, the front support cylinder (HCY11112025) generates approximately 90.5 kN at 18 MPa, and the rear support cylinder (HCYY11112027) generates approximately 76.9 kN at 20 MPa. This progression reflects the crane engineer’s assessment of the relative load shares at each outrigger position across the crane’s full operating envelope.<\/p>\n

Buyers should note that the 70 mm bore of the HCYY11112027 happens to be identical to the 70 mm bore of the outrigger extension cylinder (HCYY11112022). Despite sharing the same bore diameter, these two cylinders are completely different components \u2014 the extension cylinder has a 50 mm rod, a 1,237 mm stroke, a 140 mm installation distance, and a 20 MPa working pressure; the support cylinder has a 55 mm rod, a 420 mm stroke, a 640 mm installation distance, and the same 20 MPa working pressure. The bore coincidence is not a basis for interchangeability, and buyers must confirm all parameters \u2014 not just the bore \u2014 when selecting a replacement.<\/p>\n

Piston Rod Diameter: 55 mm \u2014 Column Stability for Compact Vertical Jack Duty<\/h3>\n

The 55 mm piston rod diameter in a 70 mm bore cylinder gives a rod-to-bore ratio of approximately 78.6%. For a vertical jack cylinder with a 420 mm stroke, this proportion provides solid resistance to column buckling under the compressive vertical reaction load. When the cylinder is extended and bearing its share of the crane’s operating weight, the piston rod acts as a structural column. The 420 mm stroke keeps the unsupported column length relatively short compared with the main outrigger support cylinder’s 640 mm stroke, which means the column stability concern is less severe at the rear position. However, the rod must still be appropriately sized \u2014 and the 55 mm diameter achieves this without over-engineering the component beyond what the rear outrigger position requires.<\/p>\n

The practical consequence for buyers is familiar by this point in the crane’s cylinder system: a replacement cylinder with a thinner piston rod \u2014 say 45 mm in an otherwise similar 70 mm bore cylinder \u2014 would have a lower column stability margin, a different retraction force characteristic, and different seal and guide bush interfaces. The rod diameter must match the original specification as precisely as the bore and stroke. The 55 mm rod is not a standard generic dimension that can be casually substituted; it is a component-specific parameter confirmed from the original engineering data.<\/p>\n

Stroke: 420 mm \u2014 The Shortest Support Stroke in the System, and Why<\/h3>\n

The 420 mm stroke of the HCYY11112027 is the shortest vertical travel in the crane’s entire outrigger support cylinder set \u2014 significantly shorter than the 640 mm stroke of the main outrigger support cylinder and the 790 mm stroke of the front outrigger support cylinder. This compact stroke is a consequence of the rear chassis geometry on this crane design. The rear of the truck crane chassis sits at a specific height above the ground that, combined with the outrigger beam end housing height at the deployed position, requires only 420 mm of vertical rod travel to lift the rear axles clear of the ground surface and to accommodate the expected range of rear site slope variation during crane setup.<\/p>\n

The short stroke makes the rear support cylinder compact and lightweight \u2014 contributing to the manageable 24 kg weight \u2014 but it also means there is less leveling margin available at the rear outrigger points. If the crane is set up on a site where the rear ground is significantly lower than the front ground \u2014 a site that slopes forward \u2014 the rear support cylinders must extend further to compensate, potentially consuming most of the available 420 mm stroke in leveling before the full axle-unloading travel is achieved. In such conditions, additional cribbing beneath the rear outrigger pads to reduce the height difference may be necessary to ensure adequate stroke is available for both leveling and axle unloading. The crane’s operating manual should specify the maximum site slope for which the outrigger system provides adequate leveling margin.<\/p>\n

As with all support cylinders in this system, a replacement with a shorter stroke than 420 mm reduces the available leveling and ground-clearance margin. A replacement with a longer stroke may cause the pad to be driven beyond the beam end housing’s mechanical travel limit, potentially damaging the housing structure or the cylinder’s lower end fitting. Stroke confirmation is mandatory before ordering.<\/p>\n

Installation Distance: 640 mm \u2014 Retracted Fit in the Rear Beam End Housing<\/h3>\n

The 640 mm installation distance is the pin-to-pin centre-to-centre dimension at the fully retracted position. This value defines exactly where the cylinder’s upper mounting pin and its lower pad connection pin must be located in the rear outrigger beam end housing when the cylinder is stowed. If a replacement cylinder has an incorrect installation distance \u2014 even by 20\u201330 mm \u2014 one of two problems will occur: either the upper pin cannot be inserted because the cylinder body is too short to bridge the gap between the two pin positions in the housing, or the cylinder body is too long and projects beyond the housing when fully retracted, preventing closure of any access cover or creating interference with adjacent rear chassis components. The installation distance is not a dimension that can be approximated \u2014 it must match the crane’s existing geometry exactly.<\/p>\n

Working Pressure: 20 MPa \u2014 Rear Support Circuit Architecture<\/h3>\n

The 20 MPa working pressure of the rear support cylinder places it at a circuit pressure level between the 12 MPa extension circuit and the 30 MPa main outrigger support circuit. This intermediate pressure reflects the intermediate force requirement of the rear support position. On most truck crane hydraulic systems, the rear support circuit is served from a dedicated circuit branch with its own pressure setting, separate from both the extension circuit and the main support circuit. Buyers replacing this cylinder must confirm the actual hydraulic pressure in the rear support circuit of their specific crane \u2014 a circuit that has been modified, rerouted, or has had its pressure-setting valve adjusted may operate at a pressure that differs from the original 20 MPa design value. A cylinder specified for 20 MPa working pressure and installed into a circuit that routinely operates at a higher pressure will experience accelerated seal wear and reduced service life.<\/p>\n

The 30 MPa maximum withstand pressure provides the 1.5\u00d7 structural safety margin above the working pressure. This withstand pressure is the peak the cylinder’s body, end caps, and seals are designed to tolerate without permanent deformation \u2014 it is not a recommended operating pressure, and the rear support circuit’s pressure-relief or pressure-reducing valve should be set and verified to maintain 20 MPa working pressure under all normal operating conditions.<\/p>\n

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Rear Outrigger Support Cylinder Installation Position \u2014 Crane Rear Chassis Vertical Jack Location and Mounting<\/h2>\n

The installation diagram below identifies the HCYY11112027 within the crane’s complete outrigger and lifting cylinder arrangement, showing the rear support cylinder positions at the ends of the deployed rear outrigger beams relative to the front outrigger positions and the rear extension cylinder positions.<\/p>\n

\"Truck<\/div>\n

Fig. 2 \u2014 Installation location diagram for HCYY11112027 and associated crane outrigger cylinders (Products 4\u20137). The rear outrigger support cylinder is identified at the rear outrigger beam end positions.<\/p>\n

The rear outrigger beam end housing that contains the HCYY11112027 is positioned at the outermost extremity of the deployed rear outrigger beam. In this location, the housing is surrounded by the rear chassis structure \u2014 counterweight brackets, slewing ring superstructure base plates, and rear hydraulic manifold components \u2014 which creates a constrained access environment for maintenance and replacement work. Field inspection of the rear support cylinder should be incorporated into the crane’s regular walk-around inspection routine, since the rear position makes it easy to overlook compared with the more visible front outrigger cylinders.<\/p>\n

The outrigger pad at the base of the HCYY11112027 makes direct contact with the ground surface at the rear outrigger point. The quality of this ground contact \u2014 the pad area, the pad condition, and the ground surface preparation beneath it \u2014 is as important to the rear support cylinder’s effective load transfer as the cylinder’s own hydraulic force generation. A damaged or missing pad, or a pad resting on an inadequately prepared surface, reduces the effective reaction load capacity at that outrigger point regardless of the cylinder’s hydraulic force. Pad condition and ground preparation should be assessed as part of every crane setup, not only during cylinder replacement or maintenance events.<\/p>\n

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Column Stability, Side Loading, and Rear Outrigger Pad Alignment<\/h2>\n

The HCYY11112027 is designed for axial compressive loading \u2014 the ground reaction force acting vertically upward through the outrigger pad and rod, balanced by the crane’s rear weight acting downward through the housing and beam. In this ideal loading condition, the 55 mm rod carries pure compression over its 420 mm extended length, and the guide bush and rod seal experience only the loads they were designed for.<\/p>\n

Several conditions introduce side loading at the rear outrigger support position, and maintenance engineers should be alert to all of them. Sloped ground beneath the rear outrigger pad produces a horizontal component in the ground reaction force \u2014 the steeper the slope, the larger the horizontal force transmitted upward into the cylinder rod through the pad connection. The rear outrigger beam end housing guide constrains the cylinder against this horizontal force, but as the guide surfaces wear, the guide bush within the cylinder head absorbs a progressively larger share of the side load. Rear outrigger guide housing wear should be assessed and corrected before installing a new support cylinder, to avoid imposing the same side-load conditions that may have contributed to the previous cylinder’s deterioration.<\/p>\n

Crane slewing dynamics at the rear outrigger position deserve specific mention. When the crane’s superstructure slews while carrying a load, the inertial force of the rotating load introduces a momentary lateral force component at each outrigger contact point. At the rear outrigger position, this slewing force has a component that acts in the direction along the rear outrigger beam \u2014 tending either to push or pull the beam in its guide channel \u2014 and a component perpendicular to the beam, acting laterally at the outrigger pad. The lateral component is transmitted into the support cylinder rod as a side load. On cranes used for frequent tandem lifts or high-speed slewing operations with heavy loads, the cumulative effect of these slewing side loads on the rear support cylinder rod seal and guide bush can be a significant contributor to cylinder wear over the machine’s service life.<\/p>\n

The rear outrigger pad’s swivel mechanism \u2014 if the pad design incorporates one \u2014 plays an important role in managing side loading. A swivel pad that tilts freely to match the ground surface converts what would otherwise be a tilted-contact side load into a clean axial reaction, keeping the force transmitted to the cylinder rod as close to vertical as possible. A seized or corroded swivel mechanism eliminates this benefit, effectively making a flat-pad geometry that transmits the full tilt angle as a side load into the rod. Swivel pad freedom of movement should be verified at every service interval.<\/p>\n

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Load Holding, Position Stability, and Rear Outrigger Circuit Safety During Long-Radius Lifts<\/h2>\n

During long-radius lifting operations \u2014 where the crane’s boom is extended near its maximum reach and the load moment on the crane is at or near its rated maximum \u2014 the rear outrigger support cylinders play a particularly critical load-holding role. At long radius, the crane’s tipping geometry places a high proportion of the total stabilizing reaction force at the rear outrigger points, and any retraction of the rear support cylinders during a long lift changes the crane’s actual tipping geometry in a way that reduces its real stability margin below the value assumed in the load chart.<\/p>\n

The hydraulic mechanism that prevents this retraction is the load-holding system in the rear support circuit \u2014 typically a pilot-operated check valve or a counterbalance valve mounted close to the cylinder’s cap-end port, which traps hydraulic pressure in the extension chamber and physically prevents the cylinder from retracting under load. The condition and correct setting of this load-holding valve is a safety-critical parameter that should be assessed and verified alongside the cylinder’s own condition at every maintenance interval. A new cylinder installed into a hydraulic circuit with a deteriorated or incorrectly adjusted load-holding valve will still exhibit position drift under load \u2014 the root cause is in the valve, not the cylinder, and both must be in correct condition for the rear support circuit to function as designed.<\/p>\n

Long duration lifts \u2014 those lasting many hours, as in bridge construction, industrial plant maintenance, or fixed-structure installation projects \u2014 present additional load-holding demands. Over several hours of hold time, even a very small rate of piston seal bypass accumulates into a measurable amount of rod retraction. Monitoring the crane’s level indicator during long hold operations provides a useful early indication of circuit drift that warrants investigation before the next planned lift. Any chassis level change of more than the crane manufacturer’s specified tolerance during a hold period should trigger a hydraulic circuit inspection before operations continue.<\/p>\n

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Inspection and Service Guidance for the Crane Rear Outrigger Support Hydraulic Cylinder<\/h2>\n

The HCYY11112027, like all support cylinders in this crane’s outrigger system, requires systematic inspection to maintain its structural integrity and load-holding reliability. The following inspection items should be incorporated into the crane’s scheduled maintenance programme.<\/p>\n

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  • Piston rod surface inspection:<\/strong> The rod surface in the wiper and rod-seal contact zone should be inspected for scoring, pitting, corrosion, and chrome layer condition. The rear chassis environment exposes the extended rod to ground-level contamination during setup \u2014 mud, road salt, grit, and moisture. A functional wiper seal is the primary defence against contamination ingress. If the wiper seal is deteriorated, replacing it promptly prevents the contamination-driven rod seal wear that typically follows.<\/li>\n
  • External seal leakage assessment:<\/strong> Visible oil accumulation around the rod seal, at port connections, or at cylinder body weld zones should be investigated immediately. Rod seal seepage at the rear support cylinder, even in small quantities, indicates seal degradation that will progress if untreated. Seepage also creates a slippery surface on the rod and housing that is a safety hazard during outrigger setup inspections.<\/li>\n
  • Piston seal condition \u2014 drift test:<\/strong> With the rear outrigger at full extension and the hydraulic control valve in neutral, observe the rear chassis level over a defined holding period as specified in the crane’s maintenance manual. Measurable chassis settlement at the rear indicates piston seal bypass, load-holding valve deterioration, or both. Both the cylinder piston seal and the load-holding valve must be assessed before returning the crane to service.<\/li>\n
  • Mounting pin and bushing condition:<\/strong> The mounting pins at the upper beam-end connection and the lower pad connection should be checked for diameter wear, surface condition, corrosion, and secure retention. Worn pins allow angular play that introduces side loading into the rod beyond what the guide housing structure can absorb. Replace worn pins and bushings before installing a replacement cylinder.<\/li>\n
  • Outrigger pad and swivel condition:<\/strong> The outrigger pad and, where fitted, its swivel mechanism should be checked for structural integrity, pad surface condition, and freedom of swivel movement. A structurally damaged pad that cannot bear the full reaction load uniformly, or a seized swivel that cannot tilt to match sloped ground, both impose abnormal loads on the support cylinder.<\/li>\n
  • Rear beam end housing guide surface condition:<\/strong> The guide surfaces within the beam end housing that constrain the cylinder against lateral movement should be inspected for wear, corrosion, and deformation. Excessive guide clearance increases the side load on the rod and guide bush. Restore guide surfaces to within the crane manufacturer’s specified clearance before fitting a replacement cylinder.<\/li>\n
  • Hydraulic line and port fitting inspection:<\/strong> The rear position exposes the cylinder’s hydraulic connections to vibration from the crane’s travel over rough terrain and from the dynamic forces of lifting operations. Check all hydraulic line connections, hose conditions, and port fittings at each service interval for signs of fatigue, leakage, or mechanical damage.<\/li>\n<\/ul>\n

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    OEM Integration and Aftermarket Procurement \u2014 Replacing the Rear Outrigger Support Cylinder Correctly<\/h2>\n

    At 24 kg, the HCYY11112027 is a physically manageable replacement unit, but it remains a hydraulic safety component whose replacement requires strict procedural compliance. The crane must be on firm, level ground with no load suspended. The rear outrigger beam must be positively secured \u2014 by its mechanical locking pin or by independent mechanical support \u2014 before the support cylinder is hydraulically isolated. The rear support circuit must be fully depressurized before hydraulic hose connections are broken, and any residual trapped pressure in the cylinder between the piston and a closed port must be released through the port fittings before the mounting pins are extracted. Failure to depressurize before disconnection risks high-pressure hydraulic fluid injection injury \u2014 a serious hazard even from a cylinder at 20 MPa.<\/p>\n

    For procurement managers overseeing fleet maintenance, the HCYY11112027 is worth holding as a stocked replacement item on high-utilization crane fleets, alongside the other outrigger support cylinders in the system. Because all four outrigger support cylinders on a crane \u2014 main, main, front-left, front-right, rear-left, rear-right \u2014 operate under similar duty cycles, they tend to require replacement at similar intervals. Planning a full outrigger cylinder replacement set for a scheduled major service interval, rather than replacing individual cylinders reactively as each fails, reduces total downtime cost and ensures consistent performance across the whole outrigger system.<\/p>\n

    OEM buyers integrating the HCYY11112027 into new crane production should provide the rear outrigger beam end housing drawing, the required mounting pin diameters and lug widths at both the upper and lower connections, the hydraulic port thread standard and positions, and the rear support circuit working pressure. A pre-production dimensional drawing exchange \u2014 issued by the cylinder manufacturer for buyer review and approval before manufacturing begins \u2014 is the recommended confirmation step for any new crane OEM integration project, ensuring dimensional traceability and providing a quality reference for incoming inspection of the first production batch.<\/p>\n

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    Technical Information Checklist \u2014 Crane Rear Outrigger Support Cylinder Inquiry<\/h2>\n

    Providing the following information enables accurate engineering review and prompt quotation for the HCYY11112027 or a compatible replacement cylinder:<\/p>\n

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    Crane make, model, and serial number<\/div>\n
    Original cylinder model number and nameplate photograph<\/div>\n
    Photographs of the existing cylinder installed in the rear outrigger beam end housing<\/div>\n
    Measured bore diameter and piston rod diameter<\/div>\n
    Measured stroke and retracted installation distance<\/div>\n
    Mounting pin diameter at upper beam-end mount and lower pad mount<\/div>\n
    Lug or clevis width at both end connections<\/div>\n
    Hydraulic port thread form, size, and positions<\/div>\n
    Confirmed hydraulic working pressure for the rear support circuit<\/div>\n
    Rear outrigger beam end housing internal dimensions (if available)<\/div>\n
    OEM engineering drawing (if available)<\/div>\n
    Required quantity and delivery schedule<\/div>\n<\/div>\n<\/div>\n

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    Frequently Asked Questions \u2014 Crane Rear Outrigger Support Hydraulic Cylinder Replacement<\/h2>\n
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    The HCYY11112027 has the same bore as the HCYY11112022 extension cylinder \u2014 can they be interchanged?<\/h3>\n

    No. Although both cylinders have a 70 mm bore, they are entirely different components with fundamentally different specifications and functions. The extension cylinder (HCYY11112022) has a 50 mm rod, a 1,237 mm stroke, and a 140 mm installation reference distance \u2014 it is a long-travel horizontal beam positioning actuator. The support cylinder (HCYY11112027) has a 55 mm rod, a 420 mm stroke, and a 640 mm installation distance \u2014 it is a compact vertical load-bearing jack. Bore diameter alone is never sufficient to identify a compatible hydraulic cylinder replacement. All parameters \u2014 bore, rod diameter, stroke, installation distance, pressure rating, and end-connection geometry \u2014 must be confirmed.<\/p>\n<\/div>\n

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    Why does the rear support cylinder have a shorter stroke than the front support cylinder?<\/h3>\n

    The stroke difference \u2014 420 mm at the rear versus 790 mm at the front \u2014 reflects the different chassis heights and ground-clearance requirements at each outrigger position. The rear of the truck crane chassis typically sits closer to the ground than the front, meaning less vertical travel is required to achieve full axle unloading at the rear. Additionally, the rear outrigger position may be designed to operate with less leveling range than the front, because the crane’s operating site is typically prepared to be reasonably level before setup, and extreme slope compensation at the rear position is less commonly required. Both stroke values are precision design parameters \u2014 neither can be substituted without engineering re-evaluation of the crane’s outrigger geometry.<\/p>\n<\/div>\n

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    My crane’s rear chassis settles slightly during long-radius lifts \u2014 is this a rear support cylinder problem?<\/h3>\n

    Rear chassis settlement during long-radius lifts is a condition that must be investigated systematically. It can result from piston seal bypass in the rear support cylinder, deterioration or incorrect setting of the load-holding valve in the rear support circuit, outrigger pad sinkage into soft ground under the high rear reaction loads typical of long-radius lifts, or a combination of these factors. The first diagnostic step is to determine whether the settlement is hydraulic \u2014 observable as a change in hydraulic circuit pressure at the rear support while the load is suspended \u2014 or mechanical, observable as pad movement into the ground surface. Hydraulic settlement requires cylinder and valve assessment; mechanical settlement requires ground preparation or larger outrigger pads. Do not substitute one diagnosis for the other without systematic testing.<\/p>\n<\/div>\n

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    Is the maximum withstand pressure of 30 MPa the same as the working pressure for the main outrigger support circuit on this crane?<\/h3>\n

    This is an important distinction. The HCYY11112027’s maximum withstand pressure of 30 MPa happens to be numerically equal to the working pressure of the main outrigger support cylinder (HCY11112023). These are entirely different values on different cylinders: the 30 MPa on the HCYY11112027 is its structural peak limit \u2014 the maximum pressure it can withstand without permanent damage \u2014 not its operating pressure. The HCYY11112027 operates at 20 MPa working pressure. If the rear support circuit were somehow pressurized to 30 MPa routinely, it would be operating at the cylinder’s withstand limit rather than its working pressure \u2014 an unsafe operating condition. The circuits for each cylinder type are independently set and must be confirmed individually.<\/p>\n<\/div>\n

    \n

    Should all four outrigger support cylinders be replaced at the same major service interval?<\/h3>\n

    On cranes with high accumulated duty cycles, replacing all four outrigger support cylinders \u2014 and assessing the extension cylinders at the same time \u2014 during a major planned service interval is often the most cost-effective approach. The four support cylinders operate under broadly similar duty conditions across a crane’s life, and if one has reached the point of seal deterioration or rod surface degradation, the others are typically approaching a similar condition. Planned simultaneous replacement eliminates the pattern of successive individual cylinder failures between major services that can otherwise result in multiple short-notice crane downtime events at commercially critical times.<\/p>\n<\/div>\n

    \n

    What is the safest way to remove the rear support cylinder from the beam end housing in the field?<\/h3>\n

    Safe removal requires the crane to be positioned on firm, level ground with no load suspended; the rear outrigger beam to be positively secured against vertical and horizontal movement \u2014 using the beam’s mechanical locking pin if fitted, supplemented by independent mechanical support if the locking pin alone is not sufficient; the rear support hydraulic circuit to be fully depressurized at the cylinder port level before any hose connections are broken; and the residual pressure trapped in the cylinder chamber between the piston and a closed port to be carefully released through the port fitting before the mounting pins are extracted. Consult the crane’s maintenance manual for the model-specific procedure and required tools before beginning the removal. Do not rely solely on the control valve closed position as hydraulic isolation \u2014 a dedicated hydraulic isolation valve or line blanking is required for safe working.<\/p>\n<\/div>\n<\/div>\n

    <\/p>\n

    \n

    Complete Crane Hydraulic Cylinder Series \u2014 System Overview<\/h3>\n

    The HCYY11112027 is the seventh and final cylinder in this truck crane’s hydraulic cylinder system. The table below summarizes the complete series for engineering reference and multi-cylinder procurement planning:<\/p>\n

    \n
    HCYY11112021<\/strong> \u2014 Main Boom Luffing | \u03a6280\u00d7\u03a6250\u00d73507 | 31.5 MPa | 1,155 kg<\/div>\n
    HCYY11112022<\/strong> \u2014 Outrigger Extension | \u03a670\u00d7\u03a650\u00d71237 | 20 MPa | 48 kg<\/div>\n
    HCY11112023<\/strong> \u2014 Outrigger Support | \u03a6140\u00d7\u03a6120\u00d7640 | 30 MPa | 123 kg<\/div>\n
    HCYY1112024<\/strong> \u2014 Front Extension | \u03a640\u00d7\u03a630\u00d71855 | 12 MPa | 24 kg<\/div>\n
    HCY11112025<\/strong> \u2014 Front Support | \u03a680\u00d7\u03a660\u00d7790 | 18 MPa | 45 kg<\/div>\n
    HCYY11112026<\/strong> \u2014 Rear Extension | \u03a640\u00d7\u03a625\u00d7635 | 12 MPa | 9 kg<\/div>\n
    HCYY11112027<\/strong> \u2014 Rear Support | \u03a670\u00d7\u03a655\u00d7420 | 20 MPa | 24 kg<\/div>\n<\/div>\n

    For multi-cylinder or complete-system procurement enquiries, please contact us with your crane model, serial number, and required quantity for each cylinder position.<\/p>\n<\/div>\n

    <\/p>\n

    \n

    Request Technical Evaluation \u2014 HCYY11112027 Crane Rear Outrigger Support Hydraulic Cylinder<\/p>\n

    Send your crane model and serial number, existing cylinder nameplate, measured dimensions, photographs, or OEM engineering drawing. Our engineering team will review your rear outrigger support cylinder replacement or integration requirements, provide a pre-production dimensional drawing for your approval, and issue a commercial quotation. Multi-cylinder and complete-system enquiries are welcome.<\/p>\n

    \n
    \ud83d\udcd0 Send OEM or Crane Drawing<\/div>\n
    \ud83d\udcf7 Send Cylinder and Housing Photos<\/div>\n
    \ud83d\udccb Request Pre-Production Drawing<\/div>\n
    \ud83d\udce6 Complete System \/ Fleet Orders<\/div>\n<\/div>\n

    Request a Quotation \u2192<\/a><\/p>\n

    Engineering review \u00b7 Pre-production dimensional drawing confirmation \u00b7 Single-cylinder, multi-cylinder, and complete outrigger system orders welcome<\/p>\n<\/div>\n<\/div>","protected":false},"excerpt":{"rendered":"

    Compact truck crane rear outrigger support jack hydraulic cylinder, \u03a670\u00d7\u03a655\u00d7420mm, 20MPa working pressure, 76.9kN theoretical force, 24kg. Rear vertical stabilizer jack for mobile crane leveling and rear-chassis load transfer. Request OEM drawing and quotation.<\/p>","protected":false},"featured_media":1719,"template":"","meta":{"_et_pb_use_builder":"","_et_pb_old_content":"","_et_gb_content_width":""},"product_brand":[],"product_cat":[114],"product_tag":[],"class_list":["post-1757","product","type-product","status-publish","has-post-thumbnail","product_cat-crane-hydraulic-cylinder","first","instock","shipping-taxable","product-type-simple"],"_links":{"self":[{"href":"https:\/\/ever-powers.com\/fr\/wp-json\/wp\/v2\/product\/1757","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/ever-powers.com\/fr\/wp-json\/wp\/v2\/product"}],"about":[{"href":"https:\/\/ever-powers.com\/fr\/wp-json\/wp\/v2\/types\/product"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/ever-powers.com\/fr\/wp-json\/wp\/v2\/media\/1719"}],"wp:attachment":[{"href":"https:\/\/ever-powers.com\/fr\/wp-json\/wp\/v2\/media?parent=1757"}],"wp:term":[{"taxonomy":"product_brand","embeddable":true,"href":"https:\/\/ever-powers.com\/fr\/wp-json\/wp\/v2\/product_brand?post=1757"},{"taxonomy":"product_cat","embeddable":true,"href":"https:\/\/ever-powers.com\/fr\/wp-json\/wp\/v2\/product_cat?post=1757"},{"taxonomy":"product_tag","embeddable":true,"href":"https:\/\/ever-powers.com\/fr\/wp-json\/wp\/v2\/product_tag?post=1757"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}