What Are the Technical Requirements for Mobile Harbour Cranes (MHC)?

Mobile Harbour Cranes (MHC) are among the core handling equipment in modern port terminals. Mounted on rubber tyres, they can move flexibly along the quayside without the need for rail tracks, combining the lifting capacity of Fixed cranes with the mobility of mobile equipment. So, what are the technical requirements that a high-performance MHC must meet? Taking the industry benchmark Liebherr LHM 420 as an example, and referencing products from brands such as MAXTECH, this article provides a systematic analysis of the key technical specifications of MHC.

I. Lifting Capacity: The Core Hard Indicator of MHC

Lifting capacity is the most fundamental and important technical parameter of an MHC, typically measured by Safe Working Load (SWL). Different MHC models cover lifting capacities ranging from dozens to hundreds of tons, meeting diverse handling needs including containers, bulk cargo, and general cargo.

Taking the Liebherr LHM 420 as an example, its maximum lifting capacity reaches 124 tons. This capacity is reflected in a load curve that decreases with increasing working radius – at radii of 10.5 to 12 meters, it can lift 124 tons at full capacity; at 16 meters, the capacity decreases to 100.1 tons; and at 30 meters, it can still lift 50.6 tons. This load-radius curve is a key indicator for evaluating MHC performance, directly determining the operational coverage the crane can achieve.

In bulk operations, the LHM 420 using a four-rope grab can handle 90 tons of cargo at radii of 10.5 to 12 meters. In standard configuration, bulk handling capacity reaches 1,500 tons per hour, which can be increased to 2,000 tons per hour with the Pactivnic system.

In container operations, the LHM 420 is equipped with a fully automatic telescopic spreader (weighing 9 tons) or a twin-lift spreader (weighing 10.7 tons). Within a 16-meter radius, it can perform single-lift container handling of 41 tons or twin-lift handling of 50 tons. In standard configuration, it can complete 32 cycles per hour, which can be increased to 38 cycles with the Pactivnic® system.

MAXTECH's MHC products also cover a wide range of lifting capacities. Its mobile harbour cranes offer lifting capacities from 10 to 200 tons, with a working radius of up to 60 meters. In mainstream configurations, MAXTECH MHCs offer lifting capacities from 65 to 125 tons, with a maximum working radius of 36 meters. Their bulk handling efficiency can reach 1,100 tons per hour.

II. Working Range: The Synergy of Radius and Height

Working radius and lifting height together determine an MHC's operational coverage.

The LHM 420 has a minimum to maximum working radius of 11 to 48 meters, a boom fulcrum height of 17.8 meters, a tower cabin height (eye level) of 24.0 meters, and an overall height (top of tower) of 32.8 meters. At minimum radius, the lifting height reaches 45 meters; at the maximum radius of 48 meters, the lifting height still reaches 29 meters.

This working range enables it to serve vessels ranging from small coastal ships to Post-Panamax class vessels.

III. Undercarriage and Mobility: The Flexible Soul Without Rails

The most prominent advantage of tyre-mounted MHCs lies in their flexible mobility without the need for rails.

The LHM 420's undercarriage design demonstrates a high level of engineering. Its standard configuration features 16 axle sets, with an optional upgrade to 24 axle sets. The overall length is 20.0 meters, and the overall width is 6.0 meters. The hydraulic suspension system prevents overloading of individual wheel sets; each wheel set can be steered independently, achieving turning at any radius and even slewing on the spot. Standard tyres use readily available trailer tyres, making spare part procurement economical and time-saving.

This undercarriage design allows MHCs to move freely along the quayside and relocate quickly between different berths, greatly enhancing the port's operational flexibility.

IV. Modular Propping System: The "Safety Foundation" for the Quay

When operating, MHCs need to transfer huge lifting loads to the quay surface. The LHM 420 features a unique modular propping system:

• Cruciform support base: Directs the load path from the boom tip to the quay surface, minimising stress on the undercarriage

• Standard supporting base: 12.5 m × 12.5 m

• Standard pad dimensions: 5.5 m × 1.8 m, with a supporting area of 9.9 m²

• Expandable design: Additional axle sets can be installed to further reduce quay loads; support pad and base sizes can be adapted to the most stringent quay load restrictions

This design enables MHCs to adapt to quays with different load-bearing capacities, ensuring safe operation even on older quays or those with strict load limitations.

V. Hydraulic and Power Systems: The Power Source for Efficient Operation

An MHC's hydraulic system and power configuration directly determine its operational efficiency and reliability.

The LHM 420 employs hydrostatic transmission technology, paired with advanced Liebherr electronics, ensuring short and productive working cycles in bulk handling. Its hoisting/lowering speed reaches up to 120 m/min, slewing speed up to 1.6 rpm, average horizontal luffing speed up to 56 m/min, and travelling speed up to 5 km/h.

In terms of power, the LHM 420 is equipped with a Liebherr-built diesel engine with a power output of 750 kW (1,020 hp). The engine complies with EU Stage V or EPA Tier 4 final emission standards. Additionally, the LHM 420 offers optional electric drive with high or low voltage connection and HVO 100 certified drives (capable of using 100% renewable diesel).

MAXTECH's MHCs, on the other hand, adopt a hybrid drive system that combines the precision of electric drive with the robust power of hydraulics. This design ensures operational efficiency while also addressing energy optimisation and environmental requirements.

VI. Intelligent Systems: The Leap from "Mechanisation" to "Intelligence"

Modern MHCs are no longer purely mechanical equipment; they are complex systems integrating a wide range of intelligent technologies.

Liebherr offers a comprehensive range of optional intelligent features for the LHM 420:

• Pactivnic®: Accumulator and electronically controlled power system for enhanced operational efficiency

• SmartGrip: Intelligent grab control

• Anti-sway system: Ensures lifting precision

• Teach-In: Semi-automatic point-to-point positioning system

• Sycratronic®: Synchronised crane control system

• Vertical Line Finder: Prevents diagonal pulling

• Collision alert system: Provides collision warnings

• LiDAT® smartApp: Smart data monitoring application

• Economy software: Fuel consumption optimisation software

• Video monitoring system and radio remote control: Enhance operational safety and convenience

In terms of intelligence, MAXTECH is also at the forefront. Its MHC products can be equipped with the optional MAX-AI Intelligent System, which includes three core modules:

1. Wire Rope Online Monitoring System: Uses electromagnetic non-destructive testing technology to detect internal and external wire breaks, wear, and corrosion in real time, automatically issuing damage reports and alerts

2. Slewing Bearing Wear Detection System: Uses high-precision displacement sensors and PLC-based intelligent analysis to measure bearing settlement (wear) in real time, automatically calculating wear trends and triggering over-limit alarms

3. Anti-sway and Precision Positioning: Actively dampens load sway during slewing and luffing, equipped with fine positioning mode for precise load placement

Furthermore, MAXTECH is developing an AI-enabled intelligent lifting robot capable of optimising lifting paths, adapting to changing conditions, and supporting semi-automatic or fully automatic operations.

VII. Environmental Protection and Sustainability: An Imperative for Green Ports

As global ports transition toward green and low-carbon operations, the environmental performance of MHCs is receiving increasing attention.

The Liebherr LHM 420 offers multiple environmental options: it can use 100% renewable diesel (HVO 100) ; optional fully biodegradable hydraulic fluids are available; and electric drive versions achieve zero emissions at the worksite.

Its noise and vibration control also meet high standards: the emission sound pressure level in the cabin is 69.3 dB(A) , the guaranteed sound power level of the machine is 110 dB(A) , upper limb vibration of the operator is less than 2.5 m/s², and whole-body vibration is less than 0.5 m/s².

VIII. Selection Recommendations: How to Choose the Right MHC?

Based on the technical requirements above, port operators should focus on the following aspects when selecting an MHC:

1. Lifting capacity and working radius: Determine the required lifting capacity and working radius based on the vessel types and cargo types the terminal primarily handles. The LHM 420's 124-ton/48-meter configuration is suitable for handling Post-Panamax and smaller vessels.

2. Quay load-bearing capacity: Assess the quay's surface load limitations and select matching propping systems and axle configurations. The LHM 420's customisable propping solutions can adapt to the most stringent quay load restrictions.

3. Power and energy: Choose between diesel drive, electric drive, or hybrid drive based on the port's power supply conditions and environmental requirements.

4. Intelligence requirements: Evaluate whether intelligent features such as anti-sway, automatic positioning, and remote monitoring are needed, as these directly affect operational efficiency and safety.

5. Total lifecycle cost: Not only consider procurement cost, but also comprehensively evaluate long-term factors such as fuel/electricity consumption, maintenance expenses, and Spare Parts availability.

The technical requirements for mobile harbour cranes (MHCs) cover multiple dimensions including lifting capacity, working range, undercarriage mobility, propping systems, power and hydraulics, intelligent control, and environmental performance. Industry benchmark products such as the Liebherr LHM 420 demonstrate outstanding performance in terms of 124-ton lifting capacity, 48-meter working radius, and 120 m/min hoisting speed. Meanwhile, brands like MAXTECH offer diverse options for ports of different scales through flexible configurations ranging from 10 to 200 tons, the MAX-AI Intelligent System, and hybrid drive technology.

Whether it is a large hub port pursuing peak performance or a small to medium-sized terminal prioritising flexibility and cost-effectiveness, understanding the core technical requirements of MHCs is the first step in making the right selection decision. As ports accelerate their automation, intelligence, and green development, the technical requirements for MHCs will continue to evolve, injecting new momentum into improving global port handling efficiency.