High-volume pulp drying is one of the toughest challenges a production manager can face. The pulp – a watery gloop – goes into one end of a huge, hot, noisy machine, and emerges at the other end as a pristine product such as paper. The combination of a fragile biological material, speed, moisture, and heat is a breakdown just waiting to happen. And when there is a breakdown, the lost production is expensive.
Breakdowns cost €20,000+ per hour
“We run this process at 25-28 tonnes/h,” says Ludwig Gustafsson, Maintenance Engineer at Ahlström-Munksjö. “At €2500 per tonne, that means downtime is very costly. But with our materials and operating conditions, it is almost inevitable. We can go for months without interruption, then suffer two stops in a week.”
Older machines – some can have been running for 30 years – were designed at a time when safety had a lower priority than productivity. “Safety rightly comes first now, and it is our focus when we make improvements to our breakdown handling. That is where our new VPG service platforms come in,” says Ludwig.
Henrik Niklasson, Operations Engineer at the Aspabruk plant, explains what happens when there is a breakdown: “Quite simply, you have to remove all the pulp being processed from the machine. The pulp line is 3.5 m wide, so access into the machine is a big problem. We use traveling service platforms that can carry up to six people. The job used to involve reaching into the machine to grab the pulp, with the obvious risk of trap and crush injuries from the cylinders.”
A safer and more ergonomic solution
“Our new platforms have made a massive improvement to safety. First, they allow the process to be mechanized, which eliminates the obvious physical risks for the workers. Second, these smooth-running platforms give more space to work, and with a more stable, upright posture,” Henrik continues. “So, alongside the improved safety, we also have better ergonomics.”
“It has been a tough project,” he says. “But now we have improved safety, we are starting to look at increasing the speed of the platform. Our team is already identifying potential areas for improvement.”
Camilla Olofsson is Project Manager, Pulp & Paper Services at Andritz (Växjö, Sweden), the manufacturer of the pulp drying machines. “These huge machines are so big that they usually have a building constructed around them, rather than being housed in existing premises. Space is always a challenge. In this case, we had to install the new VPG service platforms using a special crane – and down through a temporary hole in the roof!”
Looking to implement worldwide
“It has all been worth it, however. We worked closely with Christer Martinelle, KAM at VPG, which led to carefully thought-out and positioned barriers and gates on the platforms, The devices only open when it is safe, which has dramatically reduced the risk of workers falling and getting trapped or crushed. Our customer is very happy with VPG’s safe, precise, and quiet solution – and so am I.” For Andritz, this particular solution is only the start. “We have another 60 machines worldwide where we can apply these ideas and really make a difference in safety and performance for our customers,” concludes Camilla.
For more information about safety in the pulp and paper industry, contact key account manager Christer Martinelle, VPG: Christer.Martinelle@vpgab.com +46 (0)11 36 87 56Elevators – Mast Driven