The project is an overall commitment on Jernbro’s part, that started with Jernbro dismantling the gearbox on site. A job that included the marking of details so that even the assembly would go smoothly in the end. It is especially important when the time frame is tight. After disassembly, the somewhat complicated lifting of the large gearbox onto a truck for transport to Jernbro’s machine shop began.
− Once in place in the Avesta, we took apart the gearbox. We inspect, lift out axles step by step and measure. During the measurement, we see that the bearing positions of the gearbox are worn out in some positions. It was difficult or impossible to pull the layers off the shoulders. Unfortunately, we had to cut off the layers that cannot be dismantled. Large logs can otherwise be profitable to renovate and use in future renovations. Because of this, we describe the problem and discuss proposed measures with Alleima, says Fredrik Naess, Mechanical Technician at Jernbro in Avesta.
− To fix the problem, we measure old sleeves, draw new ones in CAD and investigate suitable material for new sleeves to put around the bearings. When the correct tolerances in sleeves and bearing positions have been determined, turning of new sleeves begins. When assembly of bearings and fitting of new sleeves is complete, the gearbox housing is put together with the sleeves for processing in the arbor mill, continues Fredrik.
Then assembly of axles, gears and couplings remain as well as checks before the gearbox can be transported back to Alleima. After cleaning the site in Sandviken, as well as various lubrication, the gearbox is lifted back into place and assembly can begin.
− During the work, we discovered some other minor problems. But by being solution-oriented, we also solved these within the time frame. My impression is that the Alleima is satisfied, especially considering that we have received more gearboxes to repair, says Fredrik.
− I am very satisfied with Jernbro’s effort, who has taken an overall responsibility for the renovation. It is professionally done. The service report, which was made after the job was done, shows that everything has been done to make the gearbox as good as possible. It is clear that Jernbro’s employees go the extra mile to ensure a good result, concludes Martin.
Alleima Tube AB is a leading manufacturer of highly refined products in advanced stainless steel and special alloys, as well as products for industrial heating.