Rebuilds require experience, planning and more planning.
Ensuring that a mill is competitive means keeping up with customer demands, market trends and embracing the potential for new technology to drive the company forward. Yet for all the possibilities offered by rebuilds, there appear to be no easy answers when it comes to actually getting the work done.
As Jaakko Poyry Consultant Arto Lintari points out, every job has its challenges, but whether a rebuild is large or small, there is little room for error. "Rebuilds are much more difficult than greenfield jobs and when you know this you know that you have to pay more attention to all features. All phases are critical on a rebuild."
Of course, as regular readers will be well aware, a successful rebuild is about far more than nuts and bolts engineering. The process starts long before anyone starts work on a single drawing. Today's successes and failures are measured in dollars and euros--not tons produced or machine speeds.
Underlining this point, Kari Knuts, senior vice president of research, development and technology at Stora Enso, Helsinki, Finland explained, "The most important thing is the financial outcome. That's the only way to judge whether a rebuild has been successful. You've got to find out what the outcome is for the competitiveness of the production line."
For Knuts, companies see a smaller degree of relative risk in the engineering element, because a rebuild is ultimately about getting a payback on investment. "First of all, you must start from where things most often go wrong. That could involve questions like how do we see the market after next year or product pricing trends. We have to be able to look ahead and it's there that I've found people in general to be far too optimistic."
As a result, Stora Enso, like many of its competitors, runs rigorous selection criteria and market analyses before it gives any project the green light. But as Knuts is keen to stress, it's also important to work with suppliers that can show they are in touch with the market as well.
"Price comes into it, of course, but you want the supplier of a rebuild to show that they really understand the rebuild in terms of the quality of the product and the competition," he said. "It's not about a certain part of the project or what the equipment can do. It's a question whether they have really understood everything about your business."
To be able to understand the whole process, of course, you need a vast array of experience. And that is precisely where the big machine suppliers such as Metso and Voith believe they can offer mills the best deal on a rebuild--peace of mind and reassurance that the people doing the work will have covered all the angles. But there is slightly more to it even than that.
According to Josef Janzer, manager for application engineering rebuilds at Voith Paper, the key to a successful rebuild lies in helping the customer clarify what is possible. "The first thing is to clarify the problems and be really clear about the goal of the rebuild," he explained.
Janzer pointed out that the process often starts long before the first formal meeting because the customer will usually have discussed a range of options with a potential supplier regarding the scale of the project and the different engineering concepts that can be applied to any particular solution.
"It's important to analyze their problems to find out what they really mean and then help determine what the customers want," he said. "For example, we could be looking at quality or efficiency or especially safety, as it is becoming more important as a trigger for investment these days."
At this point, the supplier may not even have a concrete proposal to work on. The mill team may well just be examining their options before they put in a proposal to senior management.
"We help them find the 'sweet spot' for that rebuild. We sit down with the customer and work through everything," Janzer said. "For example, if we're doing a shoe press rebuild, that will probably have an impact on felt life, steam use and so on, or we could even look at the furnish, switching to a different pulp. We have to investigate everything. It's also important to look at where the investment costs jump. Say the machine could go faster until a certain speed where we can say the rolls are good up to this point, but then we're looking at changing 65 rolls. We have to see where the investment jumps are and then develop a sweet spot for the customer so they can stay below a certain level or find out whether it makes sense to go to a bigger rebuild."
Sakari Hayrynen, vice president of rebuilds at Metso Paper, is also adamant that goal setting is key and urges prospective clients to ensure that the machine suppliers are on board at the very earliest stages of any project.
"Each job is a unique challenge because the conditions are so different at each mill and in each paper machine, so I recommend that customers discuss the issues with the experts and take enough time to plan a rebuild project," he explained.
Hayrynen pointed out that a pre-study is essential to define the technology and concept alternatives that will meet quality and production targets for the rebuild. Pilot trials may also be needed at this stage to verify the chosen concept. Even as Janzer noted, factors such as the furnish should also be examined closely, since these will have a major impact on the quality achieved (e.g. print results), runnability, and final production cost.
"A pre-study requires a lot of expertise. Much of the project's success and project execution costs are defined in the pre-study stage," Hayrynen stated. "In the case of rebuilds, it is even more important to take pre-engineering to a very detailed level. There are so many interfaces between existing and new equipment, automation, processes, etc. that without proper pre-engineering it is almost impossible to define an accurate project budget. The risk of missing equipment or bottlenecks in existing equipment is also higher."
One of the main targets in a rebuild will often be an increase in machine speed. Normally, pre-engineering will include a series of surveys on the existing equipment. If the target machine speed is significantly higher than the current speed, then machine analysis becomes an even more crucial success factor. In such cases, the supplier will closely examine the condition of the existing equipment, carry out speed-up tests to determine future speed capability, and study vibration profiles.
"You can't have anything go wrong once you've started the rebuild, so you need to know everything about the machine before you start," Janzer explained. "That means, for example, an extensive on-site investigation is needed before we start anything."
Hayrynen also believes in detailed planning for large and small rebuilds, because, as he explained, without due attention there are a host of pitfalls waiting to snare the unwary. Without adequate preparation, typical problems can include:
* all the necessary equipment is not included in the scope of the rebuild due to insufficient pre-engineering
* the interface between new and old equipment requires more work than expected
* the condition of the existing equipment is not as good as expected
* the shutdown plan is not detailed enough.
However, Hayrynen cites additional factors that he believes are also important--namely, ensuring that the check-up and commissioning times are not too short and emphasizing the importance of training, as this is often not understood or adequately taken into account. As such, he has clear ideas on factors that can ensure a positive outcome on any rebuild (see box at right).
Hannu Miettinen, technical director of UPM's Jamsankoski and Kaipola mills, also believes that attention to detail is a key factor. "You have to be very aware of certain things," he said. "For example, you have to be absolutely sure that everything fits. It might sound obvious, but even if you have the original drawings, you still need to check simply because something may have been altered slightly over the years."
Miettinen is currently in the middle of tacking the rebuild of Jamsankoski PM 6, which involves renewing the forming, press, and drying sections as well as installing a new control system for the winders. He is acutely aware of the necessity of getting the practical things right. And, as he pointed out, attention to detail is not going to be enough unless it is backed up by close cooperation between all the partners involved.
"Communication is vital. Everyone must agree who is responsible for what, including meeting rules," Miettinen said. "You will always make local modifications, so it's important to have a good network of contacts throughout the mill to make sure you've covered everything that might be affected by the rebuild. In the shutdown, you also have to be careful about shutting down common systems like the steam system. If you don't get that right, you won't be making many friends around the mill."
For UPM and others, any successful rebuild involves managing and minimizing risk factors at every stage. So even if every rebuild is technically unique, approaching each job in a systematic and cautious manner will reap dividends in the end. Unfortunately, time pressures will always play a part in any project; but with the right planning, checking and communication among team members, risks can be minimized.
Ultimately, there is one element that everyone appears to agree is crucial to every successful project. Put simply, there is no substitute for experience.
SAKARI HAYRYNEN'S TIPS FOR A SUCCESSFUL REBUILD
* Allocate enough expertise and resources to a pre-study of the project and contact machine suppliers at the earliest stage
* Define clear, realistic targets for quality and production, and define machine concept and scope according to them
* Do pre-engineering on a detailed level to define final scope and budget
* Nominate project organization with clear responsibilities and empowerment--ensure that the resources needed are available
* Emphasize importance of training before, during, and after the startup
* Prepare a detailed shutdown plan together with the machine supplier
* Reserve enough time for check-up and commissioning
* Ensure the best resources are available at the startup of the rebuild.
WHAT YOU WILL LEARN:
* The crucial factors to watch out for in a rebuild.
* The reasons why some rebuilds go wrong.
* Some "checkpoints" that will help avoid mistakes.
* "Optimization strategies determine the future," by Jim Kenny, Solutions!, February 2005. To access this article, enter the following Product Code in the search field on www.tappi.org: 05FEBS025.
JIM KENNY, CONTRIBUTING EDITOR/EUROPE
ABOUT THE AUTHOR
Jim Kenny is contributing editor/Europe for Solutions! magazine, and is based in Brussels, Belgium. He is the former vice president of editorial for Paperloop and today heads his own company, DSI. Contact him by phone at +32 2 534 4960, or by email at firstname.lastname@example.org.
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|Title Annotation:||PAPER MACHINERY|
|Publication:||Solutions - for People, Processes and Paper|
|Article Type:||Cover Story|
|Date:||Mar 1, 2005|
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