{"id":1823,"date":"2026-09-09T07:07:11","date_gmt":"2026-09-09T07:07:11","guid":{"rendered":"https:\/\/metalite.net\/?post_type=product&p=1823"},"modified":"2026-09-09T07:16:51","modified_gmt":"2026-09-09T07:16:51","slug":"hcyy11112020-crawler-crane-frame-support-hydraulic-cylinder","status":"publish","type":"product","link":"https:\/\/metalite.net\/it\/prodotto\/hcyy11112020-crawler-crane-frame-support-hydraulic-cylinder\/","title":{"rendered":"Crawler Crane Frame Support Hydraulic Cylinder \u2013 Model HCYY11112020 | \u03a6170\u00d7\u03a6150\u00d7800, 30 MPa"},"content":{"rendered":"

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Model HCYY11112020<\/p>\n

Crawler Crane Frame Support Hydraulic Cylinder<\/h2>\n

\u03a6170 \u00d7 \u03a6150 \u00d7 800 mm \u00b7 30 MPa working pressure \u00b7 262 kg \u2014 The undercarriage stabilizer that keeps the entire crane level before a single tonne leaves the ground.<\/p>\n

\u03a6170 mm Bore<\/span>
\n800 mm Stroke<\/span>
\n30 MPa \/ 40 MPa<\/span>
\n262 kg<\/span><\/div>\n<\/div>\n

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\"HCYY11112020<\/p>\n

The Frame Support Cylinder: Why Every Crawler Crane Lift Starts at Ground Level<\/h2>\n

Before the boom goes up, before the hook comes out, before any load leaves the ground \u2014 the crawler crane frame support hydraulic cylinder<\/strong> has already done its job. The HCYY11112020 is the undercarriage stabilizer that sets the crane’s main frame to a precise level position on uneven or soft ground, creating the geometric foundation that every load chart calculation assumes is in place when the crane starts lifting.<\/p>\n

This is a shorter, lower-stroke cylinder than the boom hoist or anti-tip units \u2014 800 mm of travel from a 1140 mm installation distance \u2014 but what it lacks in reach it makes up for in load density. At \u03a6170 mm bore and 30 MPa, the crane leveling cylinder<\/strong> generates approximately 681 kN of force. It transmits that force directly into the crawler frame structure, bearing a share of the crane’s total weight plus lifted load while the machine is stationary on the pads. Unlike the boom cylinders, which cycle with every lift, the frame support cylinder is loaded continuously for the entire duration of the job \u2014 sometimes days at a time on large infrastructure projects.<\/p>\n

The HCYY11112020 also has the most extreme bore-to-rod ratio in this cylinder set: \u03a6170 bore with a \u03a6150 rod \u2014 a ratio of just 1.13:1. That near-equal sizing tells you immediately that this cylinder is designed to take compression load in both directions. Whether the frame is being pushed down against the ground or being pulled up as the frame flexes under lift load, the rod section needs to be stiff enough in both modes to prevent column buckling and maintain precise frame geometry.<\/p>\n

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Technical Specifications \u2014 HCYY11112020 Frame Support Hydraulic Cylinder<\/h2>\n

\"HCYY11112020<\/p>\n

\n\n\n\n\n\n\n\n\n\n\n\n
Parameter<\/th>\nValue<\/th>\nEngineering Context<\/th>\n<\/tr>\n<\/thead>\n
Model<\/td>\nHCYY11112020<\/td>\nCrawler crane undercarriage frame support series<\/td>\n<\/tr>\n
Bore \u00d7 Rod \u00d7 Stroke<\/td>\n\u03a6170 \u00d7 \u03a6150 \u00d7 800 mm<\/td>\n1.13:1 bore-to-rod ratio \u2014 tightest of the three crane cylinders; designed for bidirectional compressive rigidity<\/td>\n<\/tr>\n
Working Pressure<\/td>\n30 MPa<\/td>\nPush force \u2248 681 kN; pull force \u2248 504 kN at rated pressure<\/td>\n<\/tr>\n
Max Withstand Pressure<\/td>\n40 MPa<\/td>\n33% safety margin \u2014 highest ratio of the three crane cylinders<\/td>\n<\/tr>\n
Stroke (Trip)<\/td>\n800 mm<\/td>\nCovers typical site ground irregularity compensation range<\/td>\n<\/tr>\n
Installation Distance<\/td>\n1140 mm<\/td>\nCompact retracted length fits within the crawler undercarriage frame depth<\/td>\n<\/tr>\n
Weight<\/td>\n262 kg<\/td>\nLightest of the three crane cylinders; fits within undercarriage maintenance access envelope<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<\/div>\n

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681 kN<\/p>\n

Push force at 30 MPa<\/p>\n<\/div>\n

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1.13:1<\/p>\n

Bore-to-rod ratio (tightest of all 3)<\/p>\n<\/div>\n

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33%<\/p>\n

Safety margin (highest of all 3)<\/p>\n<\/div>\n

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40 MPa<\/p>\n

Max withstand pressure<\/p>\n<\/div>\n<\/div>\n

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\"HCYY11112020<\/h2>\n

Why the Frame Support Cylinder Has the Highest Pressure Safety Margin of the Three \u2014 and What That Tells You<\/h2>\n

The HCYY11112020 operates at 30 MPa working pressure \u2014 slightly lower than the 31.5 MPa of the boom cylinders \u2014 yet it shares the same 40 MPa withstand rating. That gives it a 33% safety margin<\/strong>, compared to 27% on the other two. This is not accidental over-engineering. It reflects the specific load character of the frame support position.<\/p>\n

A frame support cylinder on a crawler crane is subject to ground-transmitted shock loads that the boom cylinders simply don’t see. When the crane travels over uneven terrain with the frame supported on these cylinders, every bump, rut, and obstacle translates into a vertical impulse directly into the cylinder. On soft ground \u2014 clay, saturated fill, or prepared crane mats that compress unevenly \u2014 the cylinder load can shift suddenly as the mat yields in one corner while the others hold. These dynamic ground-reaction events generate pressure spikes that are faster, shorter, and potentially higher than anything seen in the controlled luffing or anti-tip circuits. The 10 MPa margin above working pressure is the buffer that absorbs those spikes without triggering the relief valve \u2014 which, if it fired during a lift, would allow the frame to shift and the boom geometry to change instantaneously.<\/p>\n

The 1.13:1 bore-to-rod ratio deserves another look here. With a \u03a6150 rod in a \u03a6170 bore, the annular area is only 2,749 mm\u00b2 compared to the cap-end area of 22,698 mm\u00b2. That makes the retraction force (pull) approximately 504 kN \u2014 meaningfully lower than the 681 kN push force. This asymmetry is intentional: the primary load direction is compressive (pushing the frame up against gravity and crane weight), and the cylinder is optimized for that direction. The pull force is sufficient for retraction against gravity alone \u2014 it doesn’t need to pull against an opposing load.<\/p>\n

The 800 mm stroke accommodates the typical ground level variation encountered on prepared crane pads \u2014 roughly equivalent to leveling a 300-tonne crawler crane across a site with up to 400 mm of cross-slope variation at the crawler centerline distance. Beyond that range, site preparation is required before the crane can be deployed safely, regardless of cylinder specification.<\/p>\n

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Where the Crawler Crane Leveling Cylinder Earns Its Keep<\/h2>\n

The HCYY11112020 is continuously loaded at every site where the crawler crane operates. The operating environments that stress it most:<\/p>\n

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  • Soft-ground construction sites<\/strong> \u2014 where crawler mats are used and consolidation settlement during the lift changes the effective cylinder load distribution between the support points<\/li>\n
  • Bridge and infrastructure construction<\/strong> \u2014 where the crane must be set up on prepared ground adjacent to excavations or embankments, often with a cross-slope that the frame support cylinders must compensate for<\/li>\n
  • Port and marine construction<\/strong> \u2014 where the crane operates on quaysides or barge decks subject to tidal settlement, deck deflection, or wave action that creates continuous low-amplitude dynamic loading<\/li>\n
  • Power plant and industrial construction<\/strong> \u2014 where the crane must be repositioned repeatedly between picks and the frame support cylinders extend and retract dozens of times per shift during a long job<\/li>\n
  • Cold-climate winter construction<\/strong> \u2014 where frozen ground thaws unevenly under the crane mats during a long lift, creating progressive settling that the frame support cylinders must accommodate in real time<\/li>\n<\/ul>\n

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    Construction Details \u2014 Short-Stroke, High-Load, Long-Duration<\/h2>\n
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    Cylinder Barrel<\/p>\n

    Seamless forged steel (27SiMn), thick-wall construction for 40 MPa burst with additional ground-shock load case in the design analysis. Bore honed to Ra \u2264 0.4 \u03bcm for low static-friction breakout \u2014 critical for precision leveling.<\/p>\n<\/div>\n

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    Heavy-Section Rod<\/p>\n

    \u03a6150 mm 42CrMo4, hard chrome \u2265 30 \u03bcm. The massive rod cross-section (vs. the 800 mm short stroke) gives an extremely favourable slenderness ratio \u2014 Euler buckling is not a concern even under eccentric ground reaction loads.<\/p>\n<\/div>\n

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    Static Seal Design<\/p>\n

    Seals optimized for long-duration static loading rather than high-cycle dynamic operation. PU piston seals with PTFE-lined backup rings maintain consistent leak-free performance under sustained pressure hold for 24\u201372+ hour lift operations.<\/p>\n<\/div>\n

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    Foot Pad Interface<\/p>\n

    Rod end fitted with a spherical-seat steel bearing pad, compatible with standard crane mat and timber cribbing interfaces. Pad diameter and contact pressure engineered to prevent punching through standard crane mat composites.<\/p>\n<\/div>\n

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    Load-Holding Valve<\/p>\n

    Pilot-operated check valve on the cap-end port prevents any frame settlement if the hydraulic supply is isolated or lost during a lift. The frame will not retract regardless of supply pressure \u2014 the load is held mechanically by the check valve.<\/p>\n<\/div>\n

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    Corrosion Protection<\/p>\n

    External barrel: epoxy primer + polyurethane topcoat, minimum 100 \u03bcm DFT \u2014 heavier than the boom cylinders because the frame support cylinder operates in ground contact and is routinely exposed to mud, standing water, and road-salt runoff during transport.<\/p>\n<\/div>\n<\/div>\n

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    Crawler Crane Hydraulic Cylinder Installation Positions<\/p>\n

    \"Installation<\/p>\n

    The frame support cylinders sit in the undercarriage structure, extending downward to level the main frame against uneven ground before and during lifting operations.<\/p>\n<\/div>\n

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    Installation, Leveling Procedure, and Field Maintenance Notes<\/h2>\n

    At 262 kg, the HCYY11112020 is the most field-serviceable cylinder in the crawler crane system. But “manageable weight” doesn’t mean “casual installation.” Key points:<\/p>\n