이동식 항만 크레인(MHC) 동력 전달 장치용 구동축

The Pulse of the Mobile Harbor Crane: Diesel-Hydraulic Integration

The Mobile Harbor Crane (MHC) represents the pinnacle of flexible stevedoring capability. In the versatile terminals of the 네덜란드—from the coal piles of the EMO Terminal to the breakbulk quays of Vlissingen—these machines (typically represented by the Liebherr LHM series 또는 Konecranes Gottwald Model 4/6/8) must perform with surgical precision while handling immense loads. Unlike the purely electric shore power of STS cranes, the MHC often relies on an onboard powerhouse: a massive diesel prime mover (MAN, MTU, or Cummins) driving a bank of hydraulic pumps or a large generator.

The critical link in this power chain is the Main Pump Drive Shaft. This component connects the diesel engine’s flywheel to the pump splitter box (distribution gear). This is an exceptionally punishing environment. The drive shaft must transmit 100% of the engine’s torque (often exceeding 3,000 kNm in larger models) while accommodating the inherent torsional vibration pulses of a large displacement diesel engine. Furthermore, because the engine is often soft-mounted to reduce noise, and the pump tower is rigidly mounted to the superstructure, the shaft must handle constant angular and axial misalignment.

Ever-Power’s engineering approach for MHC applications focuses on Torsional Resonance Isolation. A standard industrial cardan shaft is often too rigid for the sensitive swash plates of modern axial piston pumps. We engineer our shafts with integrated damping characteristics or pair them with highly elastic flywheel couplings (Centaflex or similar equivalents) to ensure that the firing frequencies of the engine do not excite the natural frequency of the hydraulic system. This prevents the dreaded “pump chatter” that leads to catastrophic hydraulic failure.

Technical Specifications: MHC Power Series

The table below details our “Series-MHC” configurations designed for the main engine-to-pump transmission. Custom lengths are manufactured to order based on the engine room layout.

Customer Success: Pump Drive Retrofit in Vlissingen

도전 과제: A stevedoring company in Vlissingen, specializing in aluminum ingot handling, reported repeated failures on the main hydraulic pump splitter box of their 10-year-old Mobile Harbor Crane. The input shaft seals were leaking, and the gearbox bearings were failing every 2,000 hours. Vibration analysis conducted by a local Dutch firm revealed severe torsional resonance occurring at 1,400 RPM—exactly the crane’s idle-up speed during hoisting.

에버파워 솔루션: We identified that the original drive shaft (supplied by a generalist manufacturer) had a torsional stiffness that, when combined with the aging engine mounts, shifted the natural frequency into the operating range.

1. Re-Engineering: We calculated a new required stiffness and manufactured a custom “Series-MHC-Damp” shaft with a larger tube diameter but thinner wall thickness to alter the mass moment of inertia.

2. Precision Balancing: The shaft was dynamically balanced to G 2.5 precision (turbine grade) to minimize centrifugal forces.

3. 설치: We supplied a new set of high-grade 12.9 mounting hardware and a specialized alignment tool.

결과: The vibration levels at the pump tower dropped by 65%. The gearbox has now run for over 8,000 hours without a seal failure, saving the client an estimated €45,000 in downtime and parts.

Factory Customization: The “Engine Room” Specialist

MHC engine rooms are tight, hot, and difficult to access. There is no “one size fits all.” A shaft for a Liebherr LHM 400 with a MAN engine will differ from one with an MTU engine. Ever-Power’s 18 years of experience means we hold the dimensional data for most common crane-engine combinations.

Our manufacturing facility allows for 신속 프로토타이핑. If you are upgrading a crane to a Stage V emission engine, the physical dimensions of the powertrain often change. We can manufacture a custom-length spacer shaft or a completely new telescopic drive shaft to bridge the new gap, ensuring your upgraded crane is back in service within days, not months. We insert heavy-duty Mechanics® or DIN style universal joints capable of handling the high start-up torque of modern diesel engines.