Nov 24, 2020
The high speeds and efficiencies of modern paper machines leave no time for unscheduled downtime. Roll-related problems can be avoided with a roll performance agreement with Valmet. Agreement based roll maintenance operations combines Valmet's latest roll technology and knowhow with the mill's experiences to solve roll performance challenges. This means more revenue, better asset management, less risk and lower life-cycle costs in your operations. A Valmet webinar on November 18th, 2020 reviewed the roll agreement concept including case studies of what mill's have achieved. The webinar can be viewed HERE. At this webinar, attendees learned:
The presenters were Mikko Viljamaa, and David Williams. Mikko is Valmet's Director, NA Service Agreements and Davis is Roll Cover and Maintenance Technology Unit Leader. The webinar was recorded and may be found HERE or by clicking on the Related Links section of this article.
Mikko started with an overview of aftermarket agreements with Valmet and their flexibilty and partnership objectives. David then continued with an overview of a Roll Cover and Maintenance Agreement, followed by case studies of results achieved at multiple mills and concluded with examples of possible roll modernizations.
At the end of the webinar there was a comprehensive Q&A session where Mikko and David answered several questions the attendees had submitted. A sampling of these questions and their answers is presented below...
Continuous Improvement is a program where when we come and visit your mill regularly we have experts and specialists that find savings or improvements from your projects. It's a comittment from Valmet that when we have an agreement together, we promise that we can find savings or improvements from any part of your process or the mill. Typically, these continuous improvements are related to KPIs such as the volume of business. So let's say that you do X amount of volume with Valmet, against that X we promise you an amount of savings or improvements back to you. So you know that we are commited - we're in this together and Valmet is here to help and support you.
One example is access to our proprietary program Valmet Asset Manager. We can also do troubleshooting where we send people to help you with certain issues. We also have several simulation programs that can help you determine what's the best cover type, what should be the dryness out of the press, etc. We have benchmark studies that we use to compare your machine to other machines and see where you are and recommend changes to make.
Scheduled maintenenace is in regards to working rolls, suction rolls and crown control rolls. When the roll is in the machine for a short interval, 12 -18 months, and the application uses oil rather than grease, we can often perform a scheduled maintenance where the wear items are replaced. For a suction roll this would include air tubes, seal strips, other seals, etc. But, going into the bearing assembly and completely inspecting bearings and bearing fits would be reserved for a recondition type maintenance.
When it comes to heat tolerance and heat generation. Polyurethane cannot resist as much heat as rubber but it generates substantially less heat. This drastically reduced heat generation is why high temperature polyurethanes are used in highly loaded presses. When it comes to chemical resistance, rubber often outperforms poly. This is definitely true in reference to chlorine and hypochlorite. Chlorine has detrimental affects on poly and it correlates with P&J. The softer the roll, the more susceptible it is to chemical attack. Rubber, especially, HNBR, or fully saturated NBR, is especially chemically inert.
Overall machine expertise can improve your result drastically and Valmet can bring that to the table. Also the tailored programs and flexible payment programs.
Process monitoring can be done with installed accelerometers or using Valmet's iRoll or iRoll temp. We are also working on other intelligent roll components. Monitoring roll program life cycles can be done with Valmet Asset Manager which is software used to manage roll movements (in and out of the machine), store parts details, and maintenance details. This could also be integrated with the industrial internet monitoring systems, as discussed by Mikko.
The answer is yes, we definitely can bundle and yes, it definitely makes sense to bundle. The more things we can tie together, the more benefits we can find for both the mill and Valmet. And we can definitely provide more benefits and services when our people are already regularly visiting the mill as part of an agreement.
For more information about improving the performance of your rolls, watch the webinar and contact your Valmet representative.