Retrofit in intralogistics - what is important

One of the main reasons for modernizing existing systems is the discontinuation of software or hardware components from the existing system (68%). In extreme cases, a logistics system whose system control can no longer be maintained or supplied with spare parts will come to a standstill. Many companies want to counteract such an economic catastrophe at an early stage and cite the lack of further development of software solutions such as the warehouse management system as a further reason for a retrofit (37 percent). The warehouse management system is therefore being replaced more and more frequently in order to secure processes in the long term and drive forward the digital transformation.

The frequent occurrence of breakdowns (48%) also has a negative impact on plant productivity. Outdated safety technology also plays an important role due to legal requirements and with regard to the safety of their own employees (37 percent). Other reasons for the decision to retrofit include changed requirements for the company's own processes and systems (34%), a lack of compatibility with other systems (23%), a lack of support (18%) and ergonomic requirements (10%). In addition, there is the need to optimize material flow control in order to network existing systems more efficiently and avoid bottlenecks in intralogistics.

Control technology is the backbone of many industrial systems, as it monitors, controls and coordinates automated processes. This includes the control systems of individual system components, such as the storage and retrieval machine, as well as the higher-level control units. Modernization in this area was carried out by 41 percent of the study participants and, in addition to the replacement of obsolete components, is often associated with increased requirements. A retrofit often includes the replacement of position measuring systems, data transmission and safety technology - right through to the integration of Industry 4.0 technologies, such as IoT (Internet of Things).

The integration or renewal of automated storage and picking systems such as storage and retrieval machines, retrofit conveyor technology or pick-by-light systems can also be part of a retrofit in intralogistics. Material fatigue in moving or heavily used parts (e.g. the mast of a stacker crane) may require replacement. Adjustments in the area of mechanics can also include the introduction of robotics, automated guided vehicles (AGVs) and other automated solutions. For 31 percent of respondents, a retrofit included changes in this area.

In the area of control technology, 29% of respondents replaced their warehouse management system (WMS) in order to optimize the control and monitoring of all warehouse and material flow activities. Existing systems can also be optimized by renewing material flow control and visualization systems that enable user-friendly operation and monitoring of the systems. Interfaces to other IT systems in the company, such as ERP, MES or transport management software, play a decisive role in these optimizations. Compatibility with these systems can also be an important argument for a retrofit WMS.

Three main concerns emerged from the study. The majority of respondents (82%) are particularly concerned about a potential disruption to operations. If the plant has to be shut down during operation in order to carry out the modernization measures, downtime is unavoidable. At the same time, every second respondent (48 percent) fears longer downtimes due to the implementation of the project. It therefore makes sense for users and providers to carry out the changeover during a non-operational time window in order to minimize this risk.

A complete changeover within a short period of time (e.g. an extended weekend), also known as a "big bang", or during previously defined downtimes such as company vacations or the division of the changeover into several sub-projects are suitable for this.

In this context, the predictability of the project and the costs (29%) as well as adherence to the set schedule (33%) also play an important role for all respondents.

Important to know: For a third of those surveyed who had already carried out a retrofit, the fears did not subsequently materialize. Conversely, this means that for two thirds, one or the other fear was realized.

The reservations are therefore justified and require careful planning in advance and the selection of the right service provider for implementation. But which factors are decisive? And how can pitfalls be avoided?

The following three factors make it easy to recognize whether a service provider is a good fit for the upcoming project:

• At the beginning, an intensive inventory is carried out together to determine the modernization requirements.
• The partner's core competencies lie in the areas of IT, software and control technology, as these are usually the parts of the systems to be modernized.
• The existing references are suitable for the specific task.

Selecting a suitable provider is usually more challenging than for a new project. As most modernization projects in intralogistics focus on the control and instrumentation technology of the systems, it is obvious that the providers should have their own expertise in this specialist area.

Estimating the costs (as the basis for an offer) requires a great deal of time and communication on both sides, as not only the system itself but also the many interfaces of an intralogistics system are taken into consideration. Experience has shown that customers do not want to go through this process with many providers. An important factor when choosing a provider is therefore their references. On-site visits to comparable systems and an exchange of experiences with the respective operators help to get a feel for whether the provider is suitable for the customer's own requirements.

The Unitechnik study shows that the majority of the companies surveyed attach particular importance to trouble-free operation during modernization (65%) and high-quality implementation (60%). When it comes to soft factors, it is noticeable that high demands are placed on the personnel carrying out the work. Customers want fixed contact persons who are part of the provider's permanent staff, have a good understanding of the process and communicate transparently.

On the other hand, only just under a quarter of respondents (25%) classify a favorable price as an important requirement for the provider. The low weighting among the majority of study participants also shows the high economic importance of the success of the modernization measure for customers.

The automated warehouse is the central material flow hub in many companies. As a rule, it is not possible to take the entire logistics system out of operation for an extended period of time without jeopardizing the company's operations. For a retrofit, however, it is essential to shut down parts of the system temporarily. As previously mentioned, there are two possible courses of action: a "big bang", or splitting the changeover into several sub-projects.

The migration concept describes this intervention in the running system and the path from the old to the new (refurbished) system. This is of crucial importance for all parties involved in the measure. Many individual steps need to be verified and meticulously planned.

As the actual changeover in a retrofit project should be carried out as quickly as possible, the software and the interfaces to other systems must be thoroughly tested in advance. A digital twin of the system is created for this purpose. This so-called emulation behaves in exactly the same way as the physical system on site. The test environment enables the provider to simulate the live operation of the control software and warehouse management system. This allows the customer's employees to be trained in the operation of the software before the changeover.

It is important to ensure that the new components and technologies can be seamlessly integrated with the existing systems and installations. In addition to the compatibility of the software and the interfaces to other systems, there are other points that need to be considered when physically changing the existing system. This is because the new Machinery Regulation (EU) 2023/1230 was published in the Official Journal of the EU on June 29, 2023. It will apply in full from January 20, 2027 and will then repeal the existing Machinery Directive 2006/42/EC.

Under both the old directive and the new regulation, the operator is responsible for ensuring that the system complies with the statutory safety requirements. There is no grandfathering. In particular, it should be noted that the CE marking merely confirms that the system complied with the applicable regulations at the time it was placed on the market.

If a retrofit results in a "substantial modification" of the system within the meaning of the above-mentioned regulation, the CE marking expires. This in turn would mean that the system would have to be placed on the market again and a new CE marking would have to be carried out at immense expense. It is advisable to integrate a neutral safety expert into the retrofit project from the outset, who will advise the operator and provide the retrofit provider with specifications for the implementation.

For decades, the Swiss industrial company Georg Fischer (GF) worked with three different warehouse management systems at the GF Piping Systems division sites in Schaffhausen. With the aim of creating a future-proof solution from a single source, GF commissioned the German automation expert Unitechnik.

The challenge: The new warehouse management system had to replace a highly optimized system and map very complex logistics processes - without interrupting operations.

Key figures: 3 locations, 110 WMS workstations, connection of 3 automated areas (20 stacker cranes), interfaces to SAP ERP, Transporeon and various PLC protocols.

Further information: https://www.unitechnik.com/case-studies/georg-fischer.html

More about Replacement of a warehouse management system

Hans Turck GmbH & Co KG operates the central logistics center of the Turck Group in Mülheim an der Ruhr. From here, automation products such as connectors and cables, sensors, fieldbus solutions, control modules and RFID systems are shipped all over the world. The starting point for the modernization was a logistics facility from 1996 which, following several expansions, had a heterogeneous automation structure and an outdated warehouse management system .

The task was to modernize the existing technology and modify the entire material flow. The existing person-to-goods picking was converted to the goods-to-person principle. In a second expansion stage, the capacity and performance of the logistics center was doubled again. In this project, the complete changeover from the old to the new system took place over an extended weekend. The "all-time high" in order picking was achieved on the second day after the go-live.

Further information: https://www.unitechnik.com/case-studies/turck.html

The central buffer warehouse for the production of sheet metal housings for parking ticket machines and barrier systems is a 30-year-old sheet metal warehouse. All processing machines are supplied from here. Once the warehouse is up and running, so is production. The challenge was to carry out the conversion while production continued. In order to master this, Unitechnik decided, together with Scheidt & Bachmann, to carry out the conversion on several weekends without production.

First, Unitechnik converted the decentralized areas for feeding and unloading the sheet metal processing machines to the new technology. This was followed by the conversion of the storage and retrieval machines and the warehouse management system over an extended weekend. The entire control and management technology was replaced, including the position measuring system, data communication, frequency converters and, in some cases, the safety technology.

Further information: https://www.unitechnik.com/case-studies/scheidt-bachmann.html

1. The provider inspects the system and draws up a rough budget for the service based on the task and his experience.
2. The plant operator appoints an independent expert to assess the safety technology and determines how the plant needs to be converted or expanded from a safety point of view.
3. The retrofit provider draws up a detailed specification sheet describing all services and the migration concept and coordinating all interfaces.
4. Based on the specifications, the provider draws up a fixed price offer at which the plant operator can order the service.