Keeping the presses moving

It goes without saying that for a wood-based panels plant to be operating efficiently then all its components have to be working well to minimise downtime and the associated lost production output and costs.

The lubricating oil used by continuous presses is not a component that easily catches the headlines, but the humble ingredient is nevertheless crucial to keep production running.

UK-based industrial lubricating oil manufacturer Metalube has been increasingly promoting its expertise to the wood-based panel manufacturing audience in Europe

Its Metachain range of fully synthetic, high-temperature chain oils created for wood-based panel presses has been introduced onto five new presses in Europe in recent months and is now the lubricant market leader for wood panel presses across South America.

The products have been used on both Siempelkamp and Dieffenbacher presses, helping machines run cleaner with improved operational efficiency.

The Metachain range has been formulated using the latest synthetic base oils, anti[1]oxidants and anti-wear additives to meet the specific demands of chain applications in high-temperature processes, such as wood panel presses, where conventional oils fail to perform.

“To be market leader, across the whole of South America, in such a short time, is indeed an accolade for Metachain,” said Matthew Buffin, commercial manager of Metalube.

“Customers using our range of products are seeing benefits from maximising efficiency, to reduced downtime and cost savings.

“Traditionally, manufacturers of sustainable timber construction panels use specialised belt, roller, chain, and rod lubrication for their continuous presses, but these also create costly issues such as carbon deposits left by lubricants and wear on bending rods.

Mr Buffin said that many of Metalube’s customers had previously been using the same lubricants for decades.

HAMBURG SYMPOSIUM

Metalube exhibited and presented at the European Panel Federation / Fraunhofer WKI Symposium in Hamburg in October, 2022, with a stated goal to raise its profile with panel producers.

Metalube senior development chemist Emma Pates tackled the subject of evaluating chain and belt oil lubricants.

Ms Pates outlined potential issues that can arise with continuous press lubrication – a lubricant viscosity increase, formation of organic acids/varnish/sludge/deposits, plus base oil breakdown and additive depletion.

She said faster, hotter production puts more pressure on presses, with the choice of lubricant becoming all the more important. Sludge composition with wood fibre and dust merged into the lubricant can be a fire risk and costly and time-consuming to rectify.

Metalube estimated annual bending rod replacement to be about £60,000, while the annual labour required to drill rollers is about £6,000. Over-consumption of oil can be as much as £55,000. Poor quality lubricating oil thus leads to reduced lubricant life, decreased overall output and plant efficiency and higher insurance premiums. 

Ms Pates highlighted Metachain’s thermal stability, low volatility, oxidation resistance, deposit control (improved cleanliness and reduced downtime) as advantages.

Metalube uses analytical techniques such as use of the Mettler Toledo HP-DSC to assess oxidation resistance and the Mettler Toledo TGA (volatility behaviour).

In an oil aging analysis with the isothermal method at 230OC, samples were inspected and photographed at 6, 22 and 46 hours to indicate likelihood of deposit/varnish/sludge formation. The Metalube product performed well against comparative oils.

At 230OC, the oxidation rate is twice that of 220OC. “A small increase in the oil temperature can have a big impact in the oil performance,” said Ms Pates.

Metalube’s oil products are designed for operation at under 230OC to lessen oxidation. Current market performance of oil lubricants in testing gave between 2-23min resistance before the onset of oxidation.

Metalube’s next generation Metachain CB-310 and CB-633 products recorded a performance of 47.5min and 57.7min before the onset of oxidation.

In test and comparison trials, Metalube says it could achieve a 735 litres per month reduction compared to a competitor’s oil in a 70m-long press operating over 18 months.

Benefits are reduced downtime, less replacement of metal parts and less oil used.

Ms Pates said it was rare to find very high performance at a low price, with the biggest influence on cost being the base fluid.

Meanwhile, the trend to replace formaldehyde-based resins in order to reduce emissions has led to demand for pMDI resins, which is a high strength, low-temperature curing adhesive heavily utilised in OSB production.

PMDI resins are highly reactive, have enhanced stability and moisture resistance and a lower dosage is required. On the flip side they are more expensive, adhere strongly to metal surfaces and their performance is highly dependent on release agents – which means they are prone to deposit build-up.

So the release agent choice needs to be optimised (soap vs wax), aiming for synergy between products so there is no reaction with either pMDI or the release agent; helping to solubilise deposit build-up (keep components fluid).

Case studies of Metachain use at wood[1]based panels plants include a project to supply Metachain CB-100 to a large Siempelkamp press in South America. The company says annual savings of £125,000 in volume reduction alone were realised.

The customer experienced issues with the previous lubricant boiling-off and leaving the steel band dry and carbonised.

To overcome this, the dosage was significantly increased to keep the belt lubricated. The result of this over-lubrication was the collection of approximately 1,000 litres of waste oil per month, which needed to be disposed of. Metalube inspected the press and recommended Metachain CB-100 as an alternative to this application.

In another case study, which involved Metachain CB-100 and CB-200 used for three years on two Dieffenbacher continuous presses, the Metalube customer realised significant savings equating to over £60,000/ year in avoided maintenance and a 2% increase in output and plant efficiency.

The manufacturer of sustainable timber construction panels had historically used specialised belt, roller, chain and rod lubrication for its continuous presses but had encountered issues including high carbon deposits left by lubricants, and excessive wear on bending rods. To improve efficiency and optimise machine performance, Metalube recommended a trial of Metachain CB-100 for the steel belts, with Metachain CB-200 specified for the chain and roller rod system.

“Previously, when we used other ranges of wood panel lubricants, we experienced issues with high levels of carbon build up in the rollers meaning a constant requirement to drill out the residue to prevent alignment problems,” the customer said.

“Since switching to Metachain this highly labour-intensive task has been eliminated, allowing us to focus our maintenance team on other key tasks during the time-restricted shut-down periods. Wear rates on the bending rods is minimal and we are on target to reduce our annual spend on replacement rods by a minimum of 25%.”

Metalube uses German partner, Plastic Vision to market Metachain in Europe and make significant inroads into the market.

“Metachain is a relatively new lubricant but is now fully tried and tested with fantastic results,” concluded Metalube’s Matthew Buffin.