Repair of 6 PIV/MERGER reducers for an incineration plant
Express repair of 6 FRC1LD2 PIV / MERGER reducers for a major player in the environmental sector.
Following an incident at a plant converting household waste into energy, the urban heating company decided to contact us to assess their equipment and seek a rapid restart of their production.
In the middle of summer, we decided to accept this challenge and put in place a restoration strategy to accomplish the mission in record time.
Customer context: Incineration and district heating
1. Waste treatment process
The incineration plant produces electricity and heating from the treatment of the city's waste. This energy recovery makes it possible to combine the elimination of waste with the supply of heat and electricity to thousands of homes in an urban area.
It is therefore necessary for the company to have functional devices to maintain its daily activities.
Our reducers operate continuously in the heating company. They are coupled to the operation of the conveyor belt. The waste is thus handled as it is unloaded by the trucks.
PIV mechanical speed variators are fixed to the reducers to allow the speed of the belt to be varied.
In 2022, France has 122 incinerators in operation. These sites are operated directly by urban areas or very often on delegation by companies such as VEOLIA, SUEZ and their subsidiaries.
2. Gearboxes at a standstill: causes and consequences
A malfunction in the burners caused the interruption of the entire company's activity. In this case, the reducers and variators can no longer be used because they have been subjected to excessive heat. The event caused damage to a total of 6 devices.
The interruption of a key production line has major consequences. In our case, this translates into a daily loss of around €50 for the factory.
Each damaged conveyor belt equipment was carefully examined to identify the nature of the repairs required and the necessary corrective measures. In parallel, contingency plans are developed internally to mitigate delays and minimize the impact on the production line.
3. Hot – corrosive environment
Waste incineration involves breaking down material by gradually burning the waste brought in. In this environment, reducers and speed variators are faced with many temperature changes and high heat.
Speed reducers face deterioration of external parts due to the ambient environment: this can create corrosion on the devices. Fumes, dust: these emissions can degrade the devices, so it is necessary to plan their revision regularly to avoid the alteration of mechanical elements.
To learn more about the constraints on the environmental sector: https://merger.fr/environnement/
Refurbishment process: repaired 6 devices in record time
Visit by an agent on site
When the company contacted us to diagnose and repair their equipment, a MERGER agent first came on site to assess the mechanical condition of the machines. This visit allowed us to establish a quick diagnosis of the source of the problem and estimate the time it would take us to repair it in our workshop. Our goal in going on site is to minimize disruption to the company's operational process, to ensure a quick resumption of activities.
Reception of reducers and expertise
The reducers were sent to us at the workshop so that we could make a complete analysis of each reducer. Our teams proceeded to their reception and a detailed expertise.
Beforehand, a certain category of expertise was chosen to respond to the customer's problem and in view of the condition of its reducers. These expertises are supervised by the technicians and the MERGER design office. A complete file is established to highlight and explain each repair need.
Each device is carefully inspected as part of the appraisal to identify damage. We then determine the actions necessary to repair them. A complete file is given to our customers after each appraisal.
Implementation of a repair strategy
Before taking charge of the reducers at MERGER, a detailed action plan was established by the technicians and the design office in order to accelerate the revisions of the devices. We decided to proceed with a plan to recondition 3 reducers in 3 weeks and then to finalize the treatment of the other reducers once they were shipped to our customer. This approach allows the company to start from the 3nd week the reinstallation of half of its reducers and to partially resume its activity.
On-site revision and installation
After validation of the results of the expertise by our client, MERGER proceeds to repair the defective parts and overhaul the devices. In this case, this phase includes the replacement of rings, covers, shafts and gear pairs, complete cleaning of the housing as well as painting before returning to the customer.
Each reducer is subjected to tests and quality controls before being reinstalled on the customer site. Our team intervenes again to ensure that the installation is carried out efficiently and safely, saving time during a production shutdown.
Overhaul and Reconditioning: A Meticulous 7-Step Process
Complete disassembly of the casing: Careful dismantling of each device
This first step allows us to check the state of wear and potential damage to the external structure. The technician in charge of dismantling will first loosen the fasteners that allow the casing to be closed. He will then be able to separate the two parts of the casing using in particular the lifting jibs and overhead crane present in our factory.
Photos are taken at each stage of dismantling to detail the final assessment.
Complete cleaning and visual inspection: Deep cleaning, degreasing and thorough visual inspection of the kinematics
Visual inspection with measurements by control tools is an important step in the revision of a reducer. This allows in particular to identify signs of wear or breakage on the elements of the device. They can then be replaced and/or repaired to avoid an accentuation of the degradation of the operation of the device.
The person in charge of the reducer and variator will first remove the oil still present after draining. They will then clean each component with degreasers and solvents, to allow better visualization of potential damage.
Dimensional control: precise verification of dimensions to ensure conformity
The dimensional control phase is necessary to check the fit of each part. This must also ensure that the elements are put back in place during reassembly. Each part must respect the tolerances and dimensions established by the design office when designing the machine.
To do this, the MERGER technician will use measuring tools (micrometers, three-dimensional measurement, 3D scan, electronic caliper) to check the dimensions and compare them to the reference sizes.
We then record the results in our expert report in order to establish our recommendations. Depending on the conformity and the requested requirements, we establish our recommendations.
Expert report: Detailed documentation of the initial condition and the restoration steps
This document is given to each customer after an on-site or at-plant assessment MERGER. It lists all observations, decisions taken by technicians and engineers and interventions carried out on the devices. The file contains all photos, measurements and recommendations on the device.
Replacement of elements: Bearings, seals, screws, motorization, electronic control elements
For a typical overhaul of rotating machinery, it is recommended to at least change the seals, bearings, screws and sealing. In this case, we also had to replace the motor enabling the speed variation and the electronic control elements. These accessories had not withstood the heat encountered.
At this stage, the design office can also propose resizing certain elements of the kinematics. This makes it possible to optimize the strength and durability of the parts present in the speed variator and the mechanical reducer.
Quality control and testing process: Assembly steps, adjustments, checks of bearings and tooth clearances
Before the final installation of the reducer at the customer's premises, the team checks the work carried out by carrying out extended tests lasting several hours, with no-load operation or in the form of a simulation of the actual operating conditions of the device on the production line.
Quality control will check the adjustment of the bearings, the adjustment of the tooth clearances, in particular the "blue bearing" control. This crucial step in the adjustment of the gears makes it possible to validate the assembly by confirming power transmission on a majority of the gears.
Quality records are established for testing, blue range and shipping.
On-site start-up: Our technicians were present to verify proper operation and adjust the production line.
Before installing the device on the customer's production line, we plan the intervention according to the user's schedule. The dedicated "MERGER Service" team installs the device in direct connection with the production line. On-site tests are carried out before restarting the activity.
Once the final adjustments have been made to the device, our team provides the company with internal MERGER documentation to provide practical advice to ensure optimal operation of the reducer in the long term, ensuring its performance for many years.