Description
QJ1254??31??021 Hydraulic Cylinder
65mm Bore ?? 36mm Rod ?? 260mm Stroke
Ever-power presents the QJ1254??31??021 ?? a high-performance hydraulic cylinder featuring a precisely machined 65mm bore, a corrosion-resistant 36mm rod, and an optimized 260mm stroke length for seamless integration into OEM steering assemblies.
QJ1254??31??021
65 mm
36 mm
260 mm
650 mm
Ever-power has established itself as a premier industrial hydraulic cylinders through consistent quality and responsive support.
Product Overview
The QJ1254??31??021 optimizes the 65mm bore area and 36mm rod annulus relationship. This geometry produces predictable force in both extension and retraction, eliminating jerky motion. The multi-lip seal ?? PTFE-bronze wiper, PU U-cup, and nitrile O-ring ?? maintains leak-free operation from arctic cold to tropical yards. The substantial 65mm bore handles large-capacity forklifts and container handlers.
Maintenance intervals depend on duty cycle severity. Under normal warehouse conditions with clean fluid, inspect rod surface and wiper seal condition every 500 operating hours. Replace seal kit proactively at 4,000 hours to prevent unplanned downtime during critical operations.
Key Features
Balanced Force Geometry
The 65mm ?? 36mm bore-to-rod ratio is optimized to produce predictable push and pull force characteristics. This eliminates jerky steering response during rapid pressure transients when navigating tight warehouse aisles or maneuvering in congested loading dock areas.
Induction-Hardened Core
The 36mm rod core achieves HRC 28-32 through induction hardening prior to chrome deposition. This substrate hardness supports the chrome layer against denting from impact loads during dock operations, pothole traversal, and rough terrain encountered in outdoor yard applications.
Cleanroom Assembly
Pistons and seals are installed in a controlled environment maintaining particle counts below Class 1000 levels. This prevents airborne contamination from causing internal scoring of precision-honed surfaces and premature seal degradation during initial break-in period.
CMM Verification
Coordinate Measuring Machine inspection confirms all critical dimensions including bore diameter, rod concentricity, stroke length accuracy within ??0.5mm, and mounting hole positional tolerances before release from quality hold.
This demonstrates why Ever-power is preferred for custom hydraulic cylinders among fleet operators.
Technical Specifications
| Parameter | Value |
|---|---|
| Model | QJ1254??31??021 |
| Bore | 65.0 mm |
| Rod | 36.0 mm |
| Stroke | 260.0 mm |
| Mount | 650.0 mm |
| Work Pressure | 25 MPa |
| Test Pressure | 37.5 MPa |
| Burst | 62.5+ MPa |
| Temp Range | -30??C to +100??C |
| Fluid | Mineral Oil |
| Barrel | 27SiMn Seamless |
| Rod Surface | Hard Chrome 20+??m |
| Mounts | Pin Eye / Clevis |
| Ports | G1/4 or M14x1.5 |
Working Principle
Through Pascal’s principle, pressurized oil from the gear pump enters the QJ1254??31??021’s 65mm bore. At 16-21 MPa typical for forklifts, pressure acts on the piston face creating force proportional to the bore area. The 36mm rod emerges, pivoting the steering linkage through an arc from 260mm stroke and lever geometry. Reversing the wheel switches valve position, pressurizing the rod-side chamber. The differential area means extension force exceeds retraction force.
Applications
The QJ1254??31??021 is purpose-built for forklift steering systems where precise angular control and rapid response are non-negotiable. Its 65mm bore generates torque to pivot steer wheels through full arc, even when stationary and loaded. Narrow-aisle warehouses benefit from consistent steering feel reducing operator fatigue during long shifts. The unit also suits AGVs where repeatability determines navigation accuracy along defined paths. Marine terminal operations and cold storage facilities particularly value the responsive steering and low-temperature seal performance.
Brand Compatibility
Engineered for interchangeability, this unit matches mounting envelope, port geometry, and force characteristics of factory cylinders on Linde material handling equipment. Pin-eye and clevis dimensions conform to OEM specifications used by Crown and Clark, allowing direct bolt-on replacement without adapters or bracket modifications. Aftermarket distributors stock this as a universal solution for Doosan forklift families commonly found in rental and leasing fleets requiring rapid turnaround.
Visit our hydraulic cylinder manufacturer page for documentation and troubleshooting guides.
Customization Options
Ever-power’s program addresses that no two OEM installations are identical. Whether non-standard 65mm bore, specialized rod end, or alternative sealing, our engineers develop cost-effective solutions.
Material
Stainless barrel for corrosion, alloy upgrades for 36mm rod.
Surface
Nickel-chrome duplex, ceramic, phosphate, marine paint.
Temp
Low-temp NBR to -40??C, Viton to +150??C.
Testing
Extended cycling, salt spray, custom acceptance criteria.
Manufacturing & Quality
Lean workflow through machining, finishing, assembly, test. Seamless tubing CNC-turned. Diamond abrasives achieve cross-hatch on 65mm bore. Rods centerless ground, chrome-plated, eddy-current inspected. Torque-monitored assembly. Static hold, dynamic cycling, over-pressure verification.
Steel In
27SiMn, 520MPa cert
Turning
65mm bore, H8 finish
Surface
Hard chrome, 20??m+
Build
Seals, PTFE bands
Verify
Pressure, zero leak
Measure
CMM all critical dims
How to Select the Right Hydraulic Cylinder
Selecting a replacement cylinder involves evaluation of multiple interdependent parameters. Use this framework to confirm the 65mm ?? 36mm ?? 260mm unit with 650mm mounting suits your equipment. Each parameter affects performance, installation compatibility, and service life in your specific operating environment.
- Check Mounting Dimensions
Center-to-center between pins must match 650mm ??2mm. Verify pin diameter compatibility. Check hose and fitting clearance at full extension without interference. - Pressure Compatibility
Confirm system operates at ??25 MPa with this 65mm bore. Verify pump flow produces acceptable extension/retraction speed for your steering response requirements. - Specify Seal Material
Standard NBR suits mineral oil at -30??C to +100??C. Select Viton for synthetic fluids or temps above 100??C. Specify PU for water-glycol mixtures at order time.
Structural Components
The 65mm barrel is the largest structural element, thick-wall seamless steel containing 25 MPa with 4:1 safety factor. The cap-end houses the inlet port and rear mounting ?? pin-eye or clevis lug machined integrally. The piston incorporates seal grooves and wear bands centering it within the 65mm bore. The 36mm rod resists axial tension and compression; hard chrome seals against the gland and withstands environmental exposure. The threaded rod gland integrates sealing, bearing, and retention in a replaceable cartridge.
Piston Rod
36mm hard chrome plated, HV??900, Ra 0.4??m
Piston
Ductile iron with PTFE wear bands
Gland
Threaded cartridge: seal, bearing, retention
End Caps
Steel forgings, CNC-machined, ported
Ever-power Technical Deep Dive
Smart Manufacturing
The 65mm bore production line uses OPC-UA connected MES with real-time OEE dashboards. AGVs move WIP between stations. Machine vision inspects at 50??m resolution. Predictive maintenance reduced downtime 45% and improved Cpk from 1.33 to 1.67.
Frequently Asked Questions
How to measure for QJ1254??31??021?
Measure: extended pin-to-pin, retracted length, 65mm bore, 36mm rod, pin diameter. Stroke = extended ? retracted. Match within ??2mm.
What causes external leaks?
Rod leaks: wiper/rod seal failure or heat damage. Port leaks: loose fittings. Barrel leaks: O-ring wear. Most fixed with seal kit. Persistent leaks need exchange.
Technical drawings available?
PDF and STEP formats at no charge. Includes all dimensions, ports, mounts, weight, torque specs. Contact technical support with your request.
Delivery time?
Standard 36mm rod, 260mm stroke: 10-15 business days. Express: 5-7 days at 20% premium. Volume orders: phased delivery. Regional stock may ship immediately.
Get Your Quote Today
Get QJ1254??31??021 quotation within 24 hours. We cross-reference OEM part numbers. Bulk pricing and JIT programs available. Export documentation included.
Ever-power Hydraulics | ISO Certified | Export Worldwide | Ref: QJ1254??31??021
