Rossi EP Winch: a new approach to winch gearbox design
Developed for marine, construction, and mining applications, EP Winch combines a rotating housing, advanced simulations, and experimental validations to offer a compact, reliable solution that is easily integrated into customer applications.
Compactness, load capacity, reliability, and ease of integration are currently some of the main requirements in the design of gearboxes intended for winches in strategic sectors.
In addition to these requirements, there is a need to ensure reliability in the most demanding work cycles, ease of assembly, and the ability to adapt the product to the characteristics of the specific application.
From these premises comes EP Winch, the new planetary gearbox with a rotating housing developed by Rossi for winches.
The product expands a range that has represented one of the company's distinctive competencies for decades and introduces a solution designed to meet complex application needs through compactness, robustness, and customization possibilities.
"With EP Winch, we didn't just want to add a new product to our range," explains Davide Ferrari, R&D Manager for Planetary Gearboxes and Deputy CTO at Rossi. "The goal was to put our know-how at the service of the customer, developing a solution capable of better integrating into their applications and evolving along with their needs."
A rotating housing to integrate the gearbox into the drum
The distinctive feature of EP Winch is the rotating housing configuration, which allows the gearbox to be incorporated directly into the winch drum.
This solution helps contain dimensions and addresses one of the most frequent constraints in marine, mining, and construction applications, where space availability can influence the design of the entire machine.
Integrating the gearbox into the drum offers manufacturers greater design freedom and allows for optimized configurations without sacrificing the load capacity and robustness required in heavy-duty applications.
The design therefore involved every component of the transmission, with the goal of fully exploiting the structural capabilities of the system while maintaining the safety margins required by lifting and handling systems.
The gear configurations ensure high load capacity, strength, and a reduction in noise and vibration during operation.
FEM and CFD to verify structure, lubrication, and heat exchange
Alongside FEM structural analyses, used to verify the behavior of components under load, Rossi used CFD (Computational Fluid Dynamics) simulations dedicated to studying internal lubricant flows.
The analyses allowed for the optimization of the gearbox geometries and the verification of correct oil distribution under different operating conditions. One of the most delicate aspects, in fact, concerns operation at high speeds, which is required especially during no-load rope recovery, when the winch must complete the movement in the shortest possible time.
As the rotation speed increases, lubricant management becomes more complex: it is necessary to ensure that the oil correctly reaches the moving parts and, at the same time, limit the temperature increase during operation.
Through simulations, it was possible to study how much oil could circulate inside the gearbox, verify the input of fresh lubricant, and facilitate the recovery of the heated oil. The analyses therefore allowed for the identification of configurations capable of ensuring adequate lubrication even at the highest speeds expected during use.
The joint work on structure, fluid dynamics, and thermal behavior contributed to defining the gearbox's operating limits with greater precision and to improving the product's efficiency, durability, and reliability.
Testing torque and rope pull together
After numerical simulations, EP Winch was subjected to an experimental validation program in Rossi's test rooms.
A prototype with characteristics similar to those of the production gearbox was built, and test benches capable of reproducing the stresses typical of the application were prepared.
During the tests, the gearbox was operated by simultaneously applying the transmitted torque and the radial load that simulates the pull exerted by the rope on the winch. This configuration allowed for the evaluation of the product's behavior in conditions close to real ones and for the verification of multiple parameters within the same test runs.
The tests confirmed the robustness of the solutions adopted and provided the data necessary for dialogue with DNV, an international certification body particularly relevant to the marine sector.
To obtain the DNV Type Approval Certificate, Rossi did not limit itself to an internal verification conducted based on international standards, but applied specific tests and criteria required by the certifying body.
The certification thus strengthens the suitability of EP Winch for applications where documented compliance and reliability are essential requirements.
The work carried out during validation also contributed to the definition of an analysis methodology related to planetary gearboxes, which will be presented as part of an important international technical update promoted by AGMA to be held in Chicago in October 2026.
An installation designed to reduce time and risks
Ease of installation was considered from the very first design phases.
The connections to the main motors available on the market were developed to allow for motor coupling without having to disassemble structural elements of the gearbox, as can happen with other configurations.
The advantage for the customer is not just about reducing assembly times. Avoiding the disassembly of flanges or internal components limits the risk of oil leaks, contamination, and incorrect assembly, making all operations simpler and safer even when performed by non-specialized personnel.
The adopted configuration therefore facilitates both the initial mounting on the winch and subsequent maintenance activities, helping to reduce operational complexity and downtime.
From product range to application solution
EP Winch fits into Rossi's ability to start from a broad catalog and consolidated expertise in transmissions to identify the most effective configuration in relation to the application and requirements.
The evaluation does not concern only the individual gearbox; operating conditions, duty cycles, durability requirements, motorization, dimensions, and integration methods are analyzed as parts of a single system.
This expertise also allows for combining different gearboxes and technologies when the most effective configuration requires a non-standard solution.
“Partnerships with customers represent a fundamental part of our way of working,” emphasizes Stefano Cioffi, Head of Segments Marine and Construction. “Engaging with them from the early stages allows us to develop products based on real application needs and to transform every project into an opportunity for mutual improvement.”
Dialogue with the market also accompanied the initial development of EP Winch. The gearbox was, in fact, used by some Spanish charter customers in the marine sector, who were involved in a pilot project launched in 2025. Field applications allowed for the collection of concrete feedback and the verification of the product within real operating conditions.
The first projects following the launch also confirm the possibility of using EP Winch not only for new applications but also for rethinking existing systems.
In one case, the new gearbox was proposed to a customer who was using a previous configuration and had the need to reduce the costs of the installed solution. Starting from the system's operating conditions, Rossi replaced the previous configuration with a customized solution based on EP Winch, maintaining focus on the required performance and improving the overall economic sustainability of the project.
A new piece in the Rossi planetary range
EP Winch will be produced in Rossi's Lecce plants, using components sourced from the Italian and European markets.
With the new rotating housing gearbox, the company expands its offering for winches and consolidates an expertise that combines mechanical design, numerical simulation, testing, and customization capabilities.
The result is a product conceived to reduce dimensions, withstand heavy operating conditions, simplify installation, and adapt to the needs of manufacturers. A gearbox that stems from concrete application requirements and that, for this very reason, can become the basis for different solutions, developed together with the customer.
