{"id":2235,"date":"2026-06-24T08:02:32","date_gmt":"2026-06-24T08:02:32","guid":{"rendered":"https:\/\/hydrauliccylindersprice.com\/?post_type=product&p=2235"},"modified":"2026-06-24T08:02:32","modified_gmt":"2026-06-24T08:02:32","slug":"oem-single-acting-forklift-hydraulic-cylinder","status":"publish","type":"product","link":"https:\/\/hydrauliccylindersprice.com\/th\/product\/oem-single-acting-forklift-hydraulic-cylinder\/","title":{"rendered":"OEM Single Acting Forklift Hydraulic Cylinder"},"content":{"rendered":"
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OEM Single Acting Forklift Hydraulic Cylinder<\/h2>\n
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Every lift function on a forklift \u2014 raising the forks, raising the mast, raising the carriage \u2014 uses a single acting hydraulic cylinder. Not because single-acting is cheaper (it is), and not because it is simpler (it is), but because single-acting provides an inherent safety characteristic that double-acting cannot: the cylinder cannot actively pull the load down. If the hydraulic hose, the pump, or the control valve fails while the forks are raised with a 2-tonne pallet overhead, a single acting cylinder holds that pallet in place. A double-acting cylinder, with its retract port open to drain, would allow the load to free-fall.<\/p>\n

Korea Ever-Power builds this single acting cylinder as an OEM product in the lightest configuration available: 8 components, 6 kg reference weight, steel ball check valve for load holding, and no sprocket, oil pipe, or chain drive hardware. This is the bare-essentials lift cylinder for applications where an external sheave handles the chain drive, where the lowering valve is in the control manifold, and where the cylinder’s only job is to push upward and hold.<\/p>\n<\/div>\n

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Action<\/span>Single-Acting<\/span><\/div>\n
Parts<\/span>8 Only<\/span><\/div>\n
Weight<\/span>6 kg<\/span><\/div>\n
Service<\/span>OEM Custom<\/span><\/div>\n
ISO 9001<\/span>
\nMOQ 1 pc<\/span><\/div>\n<\/div>\n<\/div>\n<\/div>\n<\/section>\n

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Why Every Forklift Lift Cylinder Is Single-Acting \u2014 The Safety Architecture<\/h2>\n

The choice between single-acting and double-acting is not a performance trade-off \u2014 it is a safety decision rooted in the physics of suspended loads. On any machine that lifts loads above ground level, the cylinder type determines what happens when the hydraulic system loses pressure.<\/p>\n

\n\n\n\n\n\n\n\n\n
Failure Scenario<\/th>\nSingle-Acting Lift<\/th>\nDouble-Acting Lift (if used)<\/th>\n<\/tr>\n<\/thead>\n
Hose rupture while load raised<\/td>\nLoad holds \u2014 check valve blocks return<\/td>\nLoad descends uncontrolled<\/td>\n<\/tr>\n
Pump failure while load raised<\/td>\nLoad holds indefinitely<\/td>\nLoad may creep down via internal leakage<\/td>\n<\/tr>\n
Lowering with engine off<\/td>\nControlled via manual lowering valve<\/td>\nMay require power for controlled retract<\/td>\n<\/tr>\n
Control valve stuck in retract<\/td>\nNo retract port \u2014 cannot force descent<\/td>\nCylinder actively retracts under pressure<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<\/div>\n
Engineering principle: <\/strong>
\nOn any forklift hydraulic cylinder<\/a> that lifts a load vertically, single-acting provides a fail-safe by design \u2014 the worst-case failure mode is “load stays up” rather than “load comes down.” This is why every major forklift standard (EN 1726, ASME B56, JIS D 6201) requires or strongly recommends single-acting cylinders for the lift function.<\/span><\/div>\n<\/section>\n

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8-Part vs 27-Part \u2014 Two Lift Cylinder Architectures, Different Applications<\/h2>\n

Korea Ever-Power offers two OEM single-acting lift cylinder architectures. This page covers the 8-component bare-essentials design. The choice between them depends on whether the chain drive and internal oil routing are handled inside the cylinder or externally by the machine.<\/p>\n

\"Hydraulic-Cylinder-feature\"<\/p>\n

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This Product: 8-Component Design<\/h3>\n
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What is included:<\/strong> Housing, piston rod, steel ball check valve, U-ring, back-ring, dust wiper, Du bush, O-ring \u2014 the minimal set needed for a sealed, load-holding, single-acting lift actuator.<\/p>\n

What is external:<\/strong> Chain sheave, oil pipe, sprocket, and lowering valve are all mounted separately on the machine frame.<\/p>\n

Use when:<\/strong> The machine already has an external sheave bracket and oil routing system \u2014 the cylinder’s only job is to push and hold. Typical for aftermarket replacement cylinders, simple lift tables, farm equipment lifts, and machines where the cylinder mounts in a space-constrained position where the sprocket would not fit.<\/p>\n<\/div>\n

6 kg \u00b7 8 parts<\/div>\n<\/div>\n
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Alternative: 27-Component Design<\/h3>\n
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What is included:<\/strong> Everything in the 8-part design, plus integrated oil pipe (internal flow routing), check valve with adjustable spring, chain sprocket seat and cover, grease nipple, and full mounting hardware.<\/p>\n

What is external:<\/strong> Only the chain and the lowering valve \u2014 everything else is self-contained inside the cylinder assembly.<\/p>\n

Use when:<\/strong> Building a new mast system or lift mechanism where you want the cylinder to arrive as a complete lift subsystem. Typical for forklift mast OEMs, car lift manufacturers, and new machine designs where the assembly simplicity of an integrated unit reduces production line labour.<\/p>\n<\/div>\n

45 kg \u00b7 27 parts<\/div>\n<\/div>\n<\/div>\n<\/section>\n

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Product Specification<\/h2>\n
\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n
Product Type<\/td>\nOEM single acting hydraulic lift cylinder (bare actuator)<\/td>\n<\/tr>\n
Acting Type<\/td>\nSingle-acting only<\/td>\n<\/tr>\n
Architecture<\/td>\n8 components \u2014 steel ball check valve included, no sprocket\/oil pipe<\/td>\n<\/tr>\n
Reference Weight<\/td>\n6 kg (varies by bore and stroke)<\/td>\n<\/tr>\n
Body Material<\/td>\n20# carbon steel \/ 45# medium carbon steel<\/td>\n<\/tr>\n
Seal Options<\/td>\nParker, NOK, Hallite, Busak Shamban<\/td>\n<\/tr>\n
Load Holding<\/td>\nInternal steel ball check valve \u2014 fail-safe, gravity-seated<\/td>\n<\/tr>\n
Certification<\/td>\nISO 9001:2015, ISO 14001, ISO 45003<\/td>\n<\/tr>\n
Quality<\/td>\n100% tested \u00b7 Video inspection \u00b7 Machinery test report<\/td>\n<\/tr>\n
Service \/ MOQ<\/td>\nOEM + ODM \/ 1 piece<\/td>\n<\/tr>\n
Industries<\/td>\nManufacturing, machinery repair, farms<\/td>\n<\/tr>\n
Shipping<\/td>\nCrate or pallet \u00b7 Port: Shanghai \/ Ningbo<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<\/div>\n<\/section>\n

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8 Components \u2014 Maximum Function, Minimum Complexity<\/h2>\n

Eight components perform three functions: sealing (U-ring, back-ring, O-ring, dust wiper), guiding (Du bush), and load holding (steel ball). The housing contains the bore and the port; the piston rod transmits the force. Nothing else is needed for a single-acting cylinder where the lowering valve and chain drive are external. This minimalist architecture means fewer seals to leak, fewer machined interfaces to hold tolerance, and a faster field rebuild \u2014 a technician can disassemble, inspect, reseal, and reassemble this cylinder in under 30 minutes.<\/p>\n

\"types-of-hydraulic-cylinders-3\"<\/p>\n

\n\n\n\n\n\n\n\n\n\n\n\n\n
#<\/th>\nComponent<\/th>\nFunction in Single-Acting Context<\/th>\n<\/tr>\n<\/thead>\n
1<\/td>\nCylinder Housing Assy<\/td>\nPressure vessel and port housing \u2014 single port (bore end only)<\/td>\n<\/tr>\n
2<\/td>\nU-Ring<\/td>\nPrimary rod seal \u2014 prevents oil escape past the extending rod<\/td>\n<\/tr>\n
3<\/td>\nBack-Ring<\/td>\nAnti-extrusion support for the U-ring under pressure<\/td>\n<\/tr>\n
4<\/td>\nDust Wiper<\/td>\nPrevents external contamination from entering the seal zone<\/td>\n<\/tr>\n
5<\/td>\nPiston Rod<\/td>\nLoad-bearing member \u2014 chrome-plated, induction-hardened<\/td>\n<\/tr>\n
6<\/td>\nSteel Ball \u25c6<\/td>\nCheck valve \u2014 seats on conical bore seat to block oil return under load<\/td>\n<\/tr>\n
7<\/td>\nDu Bush<\/td>\nPTFE-lined rod guide \u2014 carries side loads, prevents metal contact<\/td>\n<\/tr>\n
8<\/td>\nO-Ring<\/td>\nStatic seal between housing sections<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<\/div>\n

\u25c6 The steel ball is the load-holding safety device. It replaces the spring-loaded check valve of the 27-part architecture with a single gravity-seated component.<\/p>\n<\/section>\n

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Where the 8-Part Single Acting Cylinder Serves<\/h2>\n

\"Single<\/p>\n

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Forklift Mast \u2014 Replacement Cylinders<\/h3>\n

When an existing forklift’s lift cylinder fails and the mast already has external sheaves and oil plumbing, the replacement cylinder only needs to provide the bare actuator function. The 8-component design drops into the existing mast channel at a fraction of the weight and cost of the 27-component integrated cylinder. This is the most common application for this product \u2014 aftermarket replacement on forklifts where the original cylinder is no longer available from the vehicle manufacturer.<\/p>\n<\/div>\n

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Farm Equipment \u2014 Compact Lift Mechanisms<\/h3>\n

Livestock chute gates, grain bin unloading floors, seed hopper lids, and small agricultural platform lifts use single acting cylinders with steel ball check valves to hold position. The 6 kg weight and compact envelope fit the tight mounting spaces available on farm equipment where cylinder access for maintenance is limited and the service interval may extend to several years.<\/p>\n<\/div>\n

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Industrial Lift Tables and Positioning Systems<\/h3>\n

Small hydraulic lift tables<\/a>, tilt tables, and vertical positioning platforms in manufacturing plants use single acting cylinders where gravity provides the return force. The integrated steel ball check valve eliminates the need for an external check valve in the hydraulic circuit, simplifying the plumbing and reducing the total component count of the lift system.<\/p>\n<\/div>\n<\/div>\n<\/section>\n

<\/p>\n

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Single Acting OEM Cylinder \u2014 Technical Questions<\/h2>\n
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If single-acting only pushes up, how does the cylinder retract \u2014 does it have a return spring?<\/h3>\n

No spring. The load weight provides the return force. When the operator opens the lowering valve on the control manifold, gravity pushes the load and carriage downward, which pushes the piston rod into the cylinder, displacing the oil back through the lowering valve to the reservoir. The lowering valve is a metering needle valve that restricts the oil flow rate \u2014 this is what controls the descent speed. Without a lowering valve (or with the valve closed), the check valve holds the oil and the load stays at height indefinitely. The short description mentioning a “spring” is a simplification \u2014 forklift lift cylinders use gravity return, not spring return.<\/p>\n<\/div>\n

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How does this 8-part cylinder differ from the 8-part cart lift cylinder?<\/h3>\n

The architecture is identical \u2014 same 8 components, same steel ball check valve principle. The difference is application scope and dimensional range. The cart lift cylinder is produced in 4 fixed models with small bores (\u03a640\u2013\u03a645), short strokes (120\u2013155 mm), and high pressures (18\u201325 MPa) specifically for hand pallet trucks. This OEM single acting cylinder has no fixed models \u2014 bore, stroke, pressure, and mounting are custom-manufactured to your specification, covering applications from pallet truck size to large industrial platform size. If your application matches one of the 4 cart models exactly, order the standard cart cylinder. If any dimension deviates, order this OEM product.<\/p>\n<\/div>\n

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Can this cylinder be used horizontally rather than vertically?<\/h3>\n

The steel ball check valve relies on gravity to seat on the conical bore seat. In a vertical orientation (port at bottom), gravity assists the seating force \u2014 the ball drops onto the seat naturally. In a horizontal orientation, the ball may not seat reliably because gravity acts perpendicular to the seating axis. For horizontal applications, specify a spring-loaded check valve (available as an upgrade option) instead of the gravity-seated steel ball. Alternatively, mount an external pilot-operated check valve in the hydraulic line if the cylinder must remain in the 8-component configuration.<\/p>\n<\/div>\n

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What is the maximum bore and stroke available in the 8-component configuration?<\/h3>\n

The 8-component architecture is practical up to approximately \u03a680 bore and 1,200 mm stroke. Above \u03a680, the piston requires additional sealing elements (wear ring, piston seal) that are not part of the 8-component bill of materials \u2014 the cylinder transitions to the 25 or 27-component architecture to accommodate the larger bore’s sealing and guiding requirements. Contact Korea Ever-Power<\/a> with your bore and stroke specification for a recommendation on the optimal architecture.<\/p>\n<\/div>\n<\/div>\n<\/section>\n

<\/p>\n

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Other Lift Cylinder Options<\/h2>\n
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\"Standard<\/p>\n
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Standard Main Lift (5 Models)<\/h3>\n

Single-acting, \u03a656\u2013\u03a660, 1,500 mm stroke. Fixed specs for standard masts.<\/p>\n<\/div>\n<\/div>\n

\"Short<\/p>\n
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27-Part Integrated Lift (OEM)<\/h3>\n

With built-in check valve, oil pipe, and sprocket. 45 kg. For new mast designs<\/p>\n<\/div>\n<\/div>\n<\/div>\n<\/section>\n<\/div>","protected":false},"excerpt":{"rendered":"

Single-acting means hydraulic power in one direction only \u2014 the cylinder pushes the load up under oil pressure, and gravity brings it down when the oil is released through a metered lowering valve. This is not a limitation \u2014 it is a deliberate safety architecture. If the hydraulic supply fails, a single-acting lift cylinder cannot pull the load down; gravity is the only lowering force, and the steel ball check valve inside the cylinder blocks the oil return path, holding the load at height until the operator deliberately opens the lowering valve. Korea Ever-Power manufactures this OEM single acting cylinder in an ultra-light 8-component design at 6 kg \u2014 the simplest and lightest lift cylinder in the product range \u2014 custom-built to your bore, stroke, and mounting specification.<\/div>","protected":false},"featured_media":2217,"comment_status":"open","ping_status":"closed","template":"","meta":{"_et_pb_use_builder":"","_et_pb_old_content":"","_et_gb_content_width":""},"product_brand":[],"product_cat":[850],"product_tag":[],"class_list":["post-2235","product","type-product","status-publish","has-post-thumbnail","product_cat-forklift-hydraulic-cylinders","first","instock","shipping-taxable","product-type-simple"],"_links":{"self":[{"href":"https:\/\/hydrauliccylindersprice.com\/th\/wp-json\/wp\/v2\/product\/2235","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/hydrauliccylindersprice.com\/th\/wp-json\/wp\/v2\/product"}],"about":[{"href":"https:\/\/hydrauliccylindersprice.com\/th\/wp-json\/wp\/v2\/types\/product"}],"replies":[{"embeddable":true,"href":"https:\/\/hydrauliccylindersprice.com\/th\/wp-json\/wp\/v2\/comments?post=2235"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/hydrauliccylindersprice.com\/th\/wp-json\/wp\/v2\/media\/2217"}],"wp:attachment":[{"href":"https:\/\/hydrauliccylindersprice.com\/th\/wp-json\/wp\/v2\/media?parent=2235"}],"wp:term":[{"taxonomy":"product_brand","embeddable":true,"href":"https:\/\/hydrauliccylindersprice.com\/th\/wp-json\/wp\/v2\/product_brand?post=2235"},{"taxonomy":"product_cat","embeddable":true,"href":"https:\/\/hydrauliccylindersprice.com\/th\/wp-json\/wp\/v2\/product_cat?post=2235"},{"taxonomy":"product_tag","embeddable":true,"href":"https:\/\/hydrauliccylindersprice.com\/th\/wp-json\/wp\/v2\/product_tag?post=2235"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}