Safely "under power"

Conductix Wampfler, manufacturer of systems for energy and data transmission to mobile consumers, has successfully completed a project to electrify rubber-tired gantry cranes (RTGs). At the TCBuen container port of the Spanish Grup TCB in Buenaventura, Colombia, the company modernized seven diesel-powered RTGs of Shanghai Zhenhua Port Machinery (ZPMC) and also supplied six Drive-In L units for new RTGs to Konecranes as part of the terminal expansion. Conductix-Wampfler was also responsible for the steel construction and installation of conductor rails with a total length of 10,400 meters.

Ten-kilometer-long conductor rail system

Andreas Burkart, project manager at Conductix-Wampfler: "In total, we equipped 25 blocks with block lengths of between 100 and 130 meters with the E-RTG Drive-In L solution as a single-side and back-to-back installation - that means over ten kilometers of conductor rails, 50 drive-in zones and 25 feed-in modules over a total system length of 2,900 meters." In order to convert the 440 V voltage to the 400 V of the ZPMC RTGs, it was necessary to install two transformers per RTG. In addition to the installation of the drive-in L-units, the switchover cabinet, control system, autosteering system and structural reinforcement in the sill beam to accommodate the drive-in L-units and transformers also had to be installed.

Thanks to its compact design, Drive-In L can be installed on both sides under the RTG's sill beam, making it "the most flexible solution of its kind on the market today". The entry or exit time of the RTG with Drive-In L is less than 20 seconds. The short drive-in zone also makes it possible to operate the RTG with power from the first row of containers.

In addition, compensation is ensured for tolerances that occur while the RTG is moving into the container block or during lifting and lowering. Coupling into the conductor rail with Drive-In-L is fully automatic and is controlled exclusively from the cab of the RTG. No ground personnel are required to change the block, which also increases safety in the terminal.

Assembled energy chain systems

RTG crane converted for electrification in the container port of TCBuen. Image: Conductix Wampfler

At igus, the term "readychain" stands for pre-assembled, customized energy chain systems. With the new readychain Basic, Standard, Standard Plus and Premium, the motion plastics specialist now has four variants of "high-performance plastics for moving applications" in its range. These provide customers with everything from a simple combination of "e-chain" and cable to fully assembled and fitted energy chain systems from a single source.

In addition to energy chains and cables for moving applications, igus also offers pre-assembled complete systems. Especially for long travel distances and heavily loaded multi-axis systems, these save time during assembly and installation and offer users predictable costs. All moving components have been developed, tested and coordinated by igus in a test laboratory. With "readychain", users receive a pre-assembled complete system from a single source directly from the manufacturer.

More than 4,000 drive cables to choose from

Project managers from igus accompany the readychain systems through all phases of the project. For example, interfaces, delivery status, assembly process and routes at the customer are taken into account just as much as the product itself. Depending on the degree of assembly, the customer can choose whether to use unassembled chainflex cables (under the sales name readychain Basic) or pre-assembled readycable cables in the e-chain (under the name readychain Standard). This is also available as a ready-to-install multi-axis system with metal sheets, which reduces the number of connection points and optimizes the connection and interfaces (readychain Standard Plus). There is an extensive readycable range with more than 4,000 different drive cables in seven quality classes. "We manufacture the pre-assembled cables, including connectors, to the exact length required," says Christian Stremlau, Head of the readychain and readycable business unit at igus.

260-meter-long cable carrier system for port crane

"A robust cable carrier system including a cable package with a particularly long travel path for a new crane system in the company's own port": This was the tender issued by the Indonesian fertilizer manufacturer Pupuk Kaltim for a new crane in the company's own port, which was to be equipped with a cable carrier including special cables on the longitudinal travel over 260 metres. Tsubaki Kabelschlepp successfully completed the project as part of an international team. An RSC (Roller Supported Chain) system based on the MC1300 energy guiding chain was used, which is fitted with "Traxline" drag chain cables.

"For the customer, the most important factor was that we were able to supply the cable drag chain and cable from a single source," says Dipl.-Ing. Winfried Sambale, Cable Product Specialist at Kabelschlepp. "Only a few suppliers can do this, especially as special medium-voltage cables were to be used here," namely highly flexible 10,000 volt drag chain cables specially designed for long travel distances, which are optimized in terms of weight and performance. This is because the lighter the electric cables are, the less drive power is required. In addition, the use of special individual cores reduces the chain radius and thus keeps the overall height of the entire cable carrier system low.

The right cable drag chain for the high-performance cable package was quickly found: "Due to the required travel length in combination with the associated performance package, we immediately opted for a rolling chain application," says Thorsten Serapinas. Manager Project Engineering at Tsubaki Kabelschlepp: "Our innovative RSC system and the chain-traxline endurance tests on the company's own outdoor test rig convinced Pupuk Kaltim".

Obertrum and Untertrum do not touch each other

Roller Supported Chains are ideal for higher additional loads with long travel distances. The upper run of the RSC system from Tsubaki Kabelschlepp never touches the lower run. The upper run of the cable drag chain runs on a guide profile with ball-bearing mounted, maintenance-free rollers. This reduces wear, prevents additional load and, due to the low tractive/push forces, the required drive force and therefore also the performance of the drives can be further reduced.

The basis for all RSC systems are standard cable carriers from Tsubaki Kabelschlepp in combination with Traxline E cables. The MC1300 was chosen for the project, a multivariable cable carrier specially designed for crane applications, which is characterized by seawater-resistant aluminium stays for extremely high stability.

For high availability and minimal wear

The requirements for conductor rails in intralogistics storage systems are diverse. High availability, long maintenance intervals and minimal wear with the smallest possible space requirement are a must, especially for fully automated systems such as those used in high-bay warehouses. Vahle has developed a universal solution specifically for this area of application with the "Vahle Multi-Träger" (VMT): Several different standard conductor rail systems can be integrated into the support profile made of galvanized sheet steel, so that an individual assignment for the different requirements in storage technology is possible.

The use of four-pole U25 busbars from Vahle is an interesting option that represents an alternative to copper conductors thanks to the use of aluminum/stainless steel conductors. During the manufacture of the conductors, a stainless steel running surface is firmly rolled into the aluminum. This combination of materials has been tried and tested for many years and is used successfully in port technology, which is susceptible to corrosion.

The U25 conductor rail is available with two different aluminum/stainless steel conductors for continuous currents of 230 and 320 A (maximum). This enables both the electrical supply of powerful storage and retrieval machines and the implementation of long storage aisles with just one power supply.

Installation using plug-in and clamping technology

With the Vahle multi girder, large suspension distances of up to 3.5 meters can be achieved. "This is sufficient for almost all applications," says the company. The steel profile of the VMT provides the necessary load-bearing capacity over this distance. Assembly using plug-in and clamping technology facilitates handling of the support profiles: Only the brackets for the VMT profile are screwed to the uprights of the shelving system, the VMT itself is then simply plugged into the brackets and clamped with spring elements. The support profiles are joined together in the same way. The compact holders for the respective conductor rail system are also simply screwed into the support profile and the conductor rails are then easily pressed into place. If necessary, the spring clamping technology enables replacement in a short time and without special tools.

Reinhard Irrgang