{"id":2265,"date":"2026-06-25T08:59:18","date_gmt":"2026-06-25T08:59:18","guid":{"rendered":"https:\/\/hydrauliccylindersprice.com\/?post_type=product&p=2265"},"modified":"2026-06-25T08:59:18","modified_gmt":"2026-06-25T08:59:18","slug":"hcyy11112005-main-boom-angle-cylinder-for-aerial-work-vehicles","status":"publish","type":"product","link":"https:\/\/hydrauliccylindersprice.com\/ceb\/product\/hcyy11112005-main-boom-angle-cylinder-for-aerial-work-vehicles\/","title":{"rendered":"HCYY11112005 Main Boom Angle Cylinder for Aerial Work Vehicles"},"content":{"rendered":"
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<\/p>\n

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<\/div>\n
Main Boom Angle \u00b7 Column Load Design \u00b7 0.91 Rod Ratio \u00b7 HCYY Series<\/div>\n

HCYY11112005 Main Boom Angle Cylinder
\nfor Aerial Work Vehicles<\/h2>\n

The main boom angle cylinder determines how high the aerial work platform reaches. It controls the angular position of the main boom \u2014 extending to raise the boom and retracting to lower it. What makes the HCYY11112005 immediately distinctive is its rod: at \u03a650, the rod is only 5 mm narrower than the \u03a655 bore. This is not a standard hydraulic cylinder proportion \u2014 it is a structural design where the rod serves as a load-bearing column, supporting the weight of the boom and platform at elevation for extended periods while personnel work overhead. The oversized rod sacrifices retract-side area (and therefore retract speed) in exchange for exceptional buckling resistance under sustained compressive loading.<\/p>\n

\n
\n
\u03a655\u00d7\u03a650<\/div>\n
Bore \u00d7 Rod<\/div>\n<\/div>\n
\n
0.91<\/div>\n
Rod-to-Bore Ratio<\/div>\n<\/div>\n
\n
506<\/div>\n
Stroke (mm)<\/div>\n<\/div>\n
\n
21 \/ 26.5<\/div>\n
MPa Work \/ Max<\/div>\n<\/div>\n
\n
32 kg<\/div>\n
Weight<\/div>\n<\/div>\n<\/div>\n<\/div>\n<\/section>\n

<\/p>\n

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Technical Specification \u2014 HCYY11112005<\/h2>\n
\n\n\n\n\n\n
Cylinder Model<\/th>\nSpecifications<\/th>\nWorking Pressure<\/th>\nMax Withstand Pressure<\/th>\nTrip<\/th>\nInstallation Distance<\/th>\nWeight<\/th>\n<\/tr>\n<\/thead>\n
HCYY11112005<\/td>\n\u03a655\u00d7\u03a650\u00d7506<\/td>\n21 MPa<\/td>\n26.5 MPa<\/td>\n506<\/td>\n1259.7<\/td>\n32 kg<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<\/div>\n
\n\n\n\n\n\n\n\n\n\n\n\n
Product Type<\/td>\nMain boom angle hydraulic cylinder for aerial work vehicle<\/td>\n<\/tr>\n
Acting Type<\/td>\nDouble-acting<\/td>\n<\/tr>\n
Function<\/td>\nMain boom elevation angle control<\/td>\n<\/tr>\n
Rod-to-Bore Ratio<\/td>\n0.91 \u2014 highest in the AWV cylinder range<\/td>\n<\/tr>\n
Body Material<\/td>\n20# \/ 45# steel<\/td>\n<\/tr>\n
Seal Options<\/td>\nParker, NOK, Hallite, Busak Shamban<\/td>\n<\/tr>\n
Certification<\/td>\nISO 9001:2015, ISO 14001, ISO 45003<\/td>\n<\/tr>\n
Quality<\/td>\n100% proof pressure tested (26.5 MPa) + leakage test<\/td>\n<\/tr>\n
MOQ \/ Warranty<\/td>\n1 piece \/ 1 year<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<\/div>\n<\/section>\n

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The 0.91 Rod-to-Bore Ratio \u2014 Why the Rod Is Nearly as Wide as the Bore<\/h2>\n

A standard hydraulic cylinder has a rod-to-bore ratio of 0.5 to 0.7 \u2014 meaning the rod is roughly half to two-thirds the diameter of the bore. The HCYY11112005 main boom angle cylinder has a ratio of 0.91 \u2014 the rod is 91% of the bore diameter. This is not a general-purpose cylinder; it is a hydraulic actuator that doubles as a structural column.<\/p>\n

\"HCYY11112004<\/p>\n

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Extend Side \u2014 Full Bore Area<\/h3>\n

The full bore area of the \u03a655 piston is 2,376 mm\u00b2. At 21 MPa, this produces approximately 49.9 kN of extension force \u2014 sufficient to push the main boom upward through its elevation arc. This is the primary working stroke: raising the boom from stowed to operating angle.<\/p>\n

Bore area: 2,376 mm\u00b2 \u00b7 Force: ~49.9 kN<\/div>\n<\/div>\n
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Retract Side \u2014 Minimal Annular Area<\/h3>\n

The annular area (bore minus rod) is only 412 mm\u00b2 \u2014 just 17% of the full bore area. At 21 MPa, the retract force is approximately 8.7 kN. This small retract force is acceptable because boom lowering is gravity-assisted: the boom’s own weight drives the descent, and the cylinder’s retract circuit primarily controls the descent speed through metering rather than providing pulling force.<\/p>\n

Annular area: 412 mm\u00b2 (17% of bore) \u00b7 Force: ~8.7 kN<\/div>\n<\/div>\n<\/div>\n
Why accept such low retract force? <\/strong>
\nBecause the primary engineering concern for the main boom angle cylinder is not force symmetry \u2014 it is buckling resistance. The cylinder must hold the boom at elevation for hours at a time, acting as a structural column under sustained compressive load. The \u03a650 rod provides the second moment of area (I = \u03c0d\u2074\/64) needed to resist Euler buckling at the 506 mm stroke extension, while the extend force (49.9 kN) provides more than adequate boom-raising capability.<\/span><\/div>\n<\/section>\n

<\/p>\n

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Rod-to-Bore Ratio Across the HCYY AWV Range<\/h2>\n

Every cylinder in the aerial work vehicle cylinder range<\/a> has a different rod-to-bore ratio \u2014 and that ratio directly reflects the cylinder’s primary engineering priority. The HCYY11112005 main boom angle cylinder sits at the extreme end of this spectrum.<\/p>\n

\n\n\n\n\n\n\n\n
Cylinder<\/th>\nBore \u00d7 Rod<\/th>\nRatio<\/th>\nDesign Priority<\/th>\n<\/tr>\n<\/thead>\n
HCYY11112004 Steering<\/td>\n\u03a640\u00d7\u03a620<\/td>\n0.50<\/td>\nBalanced extend\/retract for bidirectional steering<\/td>\n<\/tr>\n
HCYY11112003 Lifting<\/td>\n\u03a665\u00d7\u03a645<\/td>\n0.69<\/td>\nModerate rod strength for vertical lift function<\/td>\n<\/tr>\n
HCYY11112005 Main Boom Angle<\/td>\n\u03a655\u00d7\u03a650<\/td>\n0.91<\/td>\nExtreme column load \u2014 structural element<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<\/div>\n<\/section>\n

\"types-of-hydraulic-cylinders-2\"<\/p>\n

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What the Main Boom Angle Cylinder Does<\/h2>\n

The main boom angle cylinder is mounted between the turntable structure and the main boom section. When it extends, the boom rotates upward around its pivot point, increasing the boom elevation angle and raising the platform toward the working height. When it retracts, the boom rotates downward, lowering the platform. The 506 mm stroke of the HCYY11112005 translates through the boom pivot geometry into the angular range of the boom \u2014 the exact angular range depends on the specific AWV platform’s pivot arm length and mounting geometry.<\/p>\n

\"Main<\/p>\n

The 1,259.7 mm installation distance (pin-centre to pin-centre when retracted) positions the main boom angle cylinder deep within the turntable-to-boom space. This long installation distance relative to the 506 mm stroke means the cylinder operates through a relatively small percentage of its total length \u2014 approximately 40% extension ratio. This conservative extension ratio keeps the rod well-supported by the guide bush throughout the operating range, reducing the free (unsupported) rod length and further enhancing buckling resistance.<\/p>\n<\/section>\n

<\/p>\n

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Two Main Boom Angle Variants in the HCYY AWV Range<\/h2>\n

The HCYY AWV range includes two main boom angle cylinder part numbers \u2014 serving different AWV platforms with different dimensional requirements.<\/p>\n

\"hydraulic-cylinder-structure-4\"<\/p>\n

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HCYY11112005 \u2014 This Product<\/h3>\n

\u03a655\u00d7\u03a650\u00d7506, 21 MPa working \/ 26.5 MPa max, 1259.7 mm installation distance, 32 kg. Extreme 0.91 rod-to-bore ratio for column-load applications on specific AWV platforms.<\/p>\n<\/div>\n

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HCYY11112010 \u2014 Variant<\/h3>\n

A different main boom angle cylinder for a different AWV platform \u2014 different bore, rod, stroke, and mounting dimensions. Not interchangeable with the HCYY11112005. Always verify the part number on the cylinder you are replacing.<\/p>\n<\/div>\n<\/div>\n

Also in the HCYY AWV range: <\/strong>
\nHCYY11112011 \u2014 Folding Boom Angle Cylinder. This is a separate cylinder that controls the folding boom section (jib articulation), not the main boom elevation. Different function, different dimensions, different part number. See the complete HCYY cylinder catalogue<\/a> for all available part numbers.<\/span><\/div>\n<\/section>\n

<\/p>\n

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HCYY11112005 Main Boom Angle Cylinder \u2014 Technical Questions<\/h2>\n
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Why is the rod-to-bore ratio 0.91 \u2014 doesn’t that leave almost no retract force?<\/h3>\n

The annular area (\u03a655 bore minus \u03a650 rod) is only 412 mm\u00b2, producing approximately 8.7 kN of retract force at 21 MPa. This is intentionally low. The main boom angle cylinder does not need to actively pull the boom down \u2014 gravity does that work. The retract circuit primarily controls the descent speed by metering the oil flow back to the tank. The engineering priority is the rod’s second moment of area (resistance to buckling), which increases with the fourth power of diameter. The \u03a650 rod provides the structural rigidity needed to hold the boom at working elevation as a loaded column.<\/p>\n<\/div>\n

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The boom lowers faster than it rises \u2014 is this the cylinder or the valve?<\/h3>\n

The asymmetric speed is normal for this main boom angle cylinder and is a direct consequence of the 0.91 rod-to-bore ratio. At the same pump flow rate, the retract stroke moves approximately 5.8\u00d7 faster than the extend stroke because the same volume of oil fills a much smaller annular area. Combined with gravity assistance during boom lowering, the descent is noticeably faster than the ascent. This is a designed characteristic. However, if the descent speed has increased compared to when the machine was newer, the counterbalance valve may need adjustment, or the cylinder may have developed internal seal bypass.<\/p>\n<\/div>\n

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Can I use a standard \u03a655 cylinder with a \u03a635 rod as a replacement?<\/h3>\n

No. A \u03a635 rod (standard ratio 0.64) would have inadequate buckling resistance for the column loading this main boom angle cylinder sustains. The \u03a650 rod has approximately 4.2\u00d7 the second moment of area of a \u03a635 rod \u2014 directly translating to 4.2\u00d7 the critical buckling load. Using a thinner rod risks catastrophic rod buckling under sustained boom-hold loading, which could cause uncontrolled boom descent with personnel on the platform. Always match the exact bore and rod specification: \u03a655\u00d7\u03a650.<\/p>\n<\/div>\n

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Why is the maximum withstand pressure 26.5 MPa rather than the typical 1.5\u00d7 (31.5 MPa)?<\/h3>\n

The 26.5 MPa max withstand pressure represents a 1.26\u00d7 ratio over the 21 MPa working pressure. The exact test ratio is determined by the AWV platform manufacturer’s design specification \u2014 not all aerial work vehicles use the standard 1.5\u00d7 ratio. The oversized \u03a650 rod provides additional structural margin that partially compensates for the lower proof ratio, as the rod itself absorbs a significant portion of the compressive load independently of the hydraulic pressure. Every HCYY11112005 is proof-tested at 26.5 MPa before shipment. Contact Korea Ever-Power<\/a> for a replacement quotation.<\/p>\n<\/div>\n<\/div>\n<\/section>\n

\"why-choose-us-1\"<\/p>\n

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Customer Reviews<\/h2>\n
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David T.<\/strong>
\nVerified Purchase \u00b7 May 2025<\/span><\/div>\n
\u2605\u2605\u2605\u2605\u2605<\/div>\n

Replaced the main boom angle cylinder on our AWV \u2014 the original had developed internal bypass that caused the boom to slowly settle under load. The \u03a650 rod on this HCYY11112005 is noticeably thicker than what I’d expect on a \u03a655 bore cylinder \u2014 when I first saw it I thought it was the wrong part. But the specs matched perfectly: \u03a655\u00d7\u03a650\u00d7506, 1259.7 mm pin centres, everything aligned. Boom now holds steady at any angle with zero drift during our 30-minute hold test. Excellent product.<\/p>\n<\/div>\n

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ProLift Equipment Services<\/strong>
\nVerified Purchase \u00b7 March 2025<\/span><\/div>\n
\u2605\u2605\u2605\u2605\u2605<\/div>\n

We ordered the HCYY11112005 (boom angle) together with the HCYY11112003 (lifting) and HCYY11112004 (steering) for a complete AWV cylinder overhaul. All three arrived in one shipment, individually packaged with test certificates showing the correct proof pressures \u2014 26.5 MPa for the boom angle, 27 MPa for the lifting, 30 MPa for the steering. Our technician installed all three in one day. The machine is back in service and performing at OEM standard. Total cost for all three was roughly 45% of the OEM channel quote for just the boom angle cylinder.<\/p>\n<\/div>\n

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Murat K.<\/strong>
\nVerified Purchase \u00b7 January 2025<\/span><\/div>\n
\u2605\u2605\u2605\u2605\u2606<\/div>\n

Cylinder works well, correct dimensions. The installation was more challenging than expected \u2014 at 32 kg and 1,259 mm long (retracted), it’s awkward to manoeuvre into the turntable space without a second pair of hands. The pin alignment at both ends took some patience. Once installed, the boom angle control is smooth and precise. The boom descends noticeably faster than it rises \u2014 I initially thought this was a fault, but I understand now it’s the design of the \u03a650 rod annular area. Four stars for the difficult installation, not for the cylinder quality.<\/p>\n<\/div>\n

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Renato S.<\/strong>
\nVerified Purchase<\/span><\/div>\n
\u2605\u2605\u2605\u2605\u2605<\/div>\n

Second main boom angle cylinder we’ve purchased from Ever-Power. Same quality as the first. The \u03a650 rod chrome is flawless \u2014 critical because this rod is under compression for hours at a time when the boom is holding position. Any surface defect that initiates a corrosion site would compromise the structural integrity. Delivery was 22 days to Brazil. No complaints. Will order again when the next AWV in our fleet reaches its service interval.<\/p>\n<\/div>\n<\/div>\n<\/section>\n

<\/p>\n

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Related HCYY AWV Cylinders<\/h2>\n
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\"HCYY<\/p>\n

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HCYY11112003 Lifting<\/h3>\n

\u03a665\u00d7\u03a645\u00d7840, 18\/27 MPa, 27 kg. Primary platform lift.<\/p>\n<\/div>\n<\/div>\n

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\"HCYY<\/p>\n

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HCYY11112004 Steering<\/h3>\n

\u03a640\u00d7\u03a620\u00d7125, 20\/30 MPa, 2.8 kg. Platform steering.<\/p>\n<\/div>\n<\/div>\n

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\"HCYY<\/p>\n

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HCYY Levelling & Folding<\/h3>\n

008 levelling, 011 folding boom angle \u2014 complete boom set.<\/p>\n<\/div>\n<\/div>\n<\/div>\n<\/section>\n<\/div>","protected":false},"excerpt":{"rendered":"

HCYY11112005 is the OEM part number for the main boom angle cylinder on specific aerial work vehicle platforms. This cylinder controls the angular position of the main boom \u2014 the primary elevation actuator that determines the platform’s working height and reach. At \u03a655 bore with a \u03a650 rod, the HCYY11112005 has a rod-to-bore ratio of 0.91 \u2014 the highest in the entire Korea Ever-Power AWV cylinder range. This extreme ratio means the rod occupies 83% of the bore cross-section, leaving only 17% as annular area. The design prioritises structural rigidity: the massively oversized rod resists buckling under the compressive column loads that the boom angle cylinder sustains when holding the boom at working elevation. 506 mm stroke, 21 MPa working pressure, 26.5 MPa maximum withstand pressure, 32 kg.<\/div>","protected":false},"featured_media":2264,"comment_status":"open","ping_status":"closed","template":"","meta":{"_et_pb_use_builder":"","_et_pb_old_content":"","_et_gb_content_width":""},"product_brand":[],"product_cat":[849],"product_tag":[],"class_list":["post-2265","product","type-product","status-publish","has-post-thumbnail","product_cat-aerial-work-vehicle-hydraulic-cylinders","first","instock","shipping-taxable","product-type-simple"],"_links":{"self":[{"href":"https:\/\/hydrauliccylindersprice.com\/ceb\/wp-json\/wp\/v2\/product\/2265","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/hydrauliccylindersprice.com\/ceb\/wp-json\/wp\/v2\/product"}],"about":[{"href":"https:\/\/hydrauliccylindersprice.com\/ceb\/wp-json\/wp\/v2\/types\/product"}],"replies":[{"embeddable":true,"href":"https:\/\/hydrauliccylindersprice.com\/ceb\/wp-json\/wp\/v2\/comments?post=2265"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/hydrauliccylindersprice.com\/ceb\/wp-json\/wp\/v2\/media\/2264"}],"wp:attachment":[{"href":"https:\/\/hydrauliccylindersprice.com\/ceb\/wp-json\/wp\/v2\/media?parent=2265"}],"wp:term":[{"taxonomy":"product_brand","embeddable":true,"href":"https:\/\/hydrauliccylindersprice.com\/ceb\/wp-json\/wp\/v2\/product_brand?post=2265"},{"taxonomy":"product_cat","embeddable":true,"href":"https:\/\/hydrauliccylindersprice.com\/ceb\/wp-json\/wp\/v2\/product_cat?post=2265"},{"taxonomy":"product_tag","embeddable":true,"href":"https:\/\/hydrauliccylindersprice.com\/ceb\/wp-json\/wp\/v2\/product_tag?post=2265"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}