- Email: [email protected]
Guide to marine seals renewed
NEWS contribution to Nicholsons ongoing drive to improve part quality and process control.
and International Shipsuppliers & Services Association (ISSA) references for easy identification.
Contact: Nicholsons Sealing Technologies Ltd, Amos Drive, Greencroft Industrial Park, Stanley, Co. Durham DH9 7YE, UK. Tel: +44 1207 523010, Fax: +44 1207 523011, Email: [email protected], Web: www.nicholsons.co.uk
Contact: James Walker & Co Ltd, Marine Industry Support Team, 1 Millennium Gate, Westmere Drive, Crewe, Cheshire CW1 6AY, UK. Tel: +44 1270 536000, Fax: +44 1270 536100, Email: [email protected], Web: www.jameswalker.biz
Conformal coating coats complex products
Latest diesel needs special gaskets
G
reene, Tweed has introduced an exclusive, proprietary, conformal, PTFE coating capability, Enduro LF10. This coating is intended for use on complex semiconductor components where it can potentially enhance performance. It can be applied to elastomeric, thermoplastic or metal substrates and can help reduce friction and wear. The coating is deposited on component surfaces in a low-temperature environment, allowing the coating of delicate structures, nonplanar surfaces and temperature-sensitive materials. It has good adhesion, high purity and high conformality, thereby reducing the friction or sticking force between two components. Test results indicate that reductions of up to 70% are possible. Coating thickness can vary from 1 to 10 μm depending on whether the material is a solid substrate or flexible such as elastomer.
Contact: Greene, Tweed and Co, 2075 Detwiler Road, PO Box 305, Kulpsville, PA 19443-0305, USA. Tel: +1 215 256 9521, Fax: +1 215 256 0189, Email: [email protected], Web: www.gtweed.com
Guide to marine seals renewed
T
he new edition of James Walker’s sealing guide to marine applications is now available worldwide. This guide describes the wide ranges of products and services supplied to marine operators and shipbuilders, and gives contact details for James Walker’s official marine distributors around the globe. A quick reference chart provides performance data and recommended duties for the most popular products, followed by expanded entries with International Marine Purchasing Association (IMPA)
February 2009
T
he new four-cylinder diesel engines from Mercedes-Benz are intended to set new standards in consumption and exhaust emissions and will rely on gasket technology from Victor Reinz. In addition to the cylinder-head gaskets, a multi-layer steel gasket with wave stopper design, the company is supplying heat shields and special gaskets for the exhaust gas recirculation path in the innovative diesel engine. The new powertrain with two-stage turbocharging and fourth-generation common-rail technology features up to 150 kW, 204 hp, output with a displacement of 2143 cc. The maximum ignition pressure is 200 bar, which has presented the developers with a special challenge: to design a durable and economical cylinder-head gasket that can be used in an entire generation of engines. ‘The cylinder-head gasket for the new OM 651 diesel engine from Mercedes-Benz is a multi-layer steel gasket with stainless-steel cover and bottom and a full-surface fluoroelastomer coating. In combination with the plastic/elastic behavior of the wavestopper, this gasket achieves optimal results in all operating conditions,’ explained project manager Thomas Eberle of Victor Reinz in Neu-Ulm. ‘The engine will be used in the future in many model lines, up to and including the Sprinter. That’s why it was important to us to present a solution from the start that matched the development potential of this diesel engine.’ The exhaust gas recirculation path uses metal beaded gaskets with an elastomer coating. These are partially preassembled at Victor Reinz in Neu-Ulm, Germany, and delivered as a module directly to the assembly line.
Contact: Reinz-Dichtungs-GmbH, Reinzstrasse 3–7, D-89233 Neu-Ulm, Germany. Tel: +49 731 7046 369, Fax: +49 731 7046 400, Email: [email protected], Web: www.reinz.com
BOB’S BIT The Donald Julius Groen Prize Lecture at the Institution of Mechanical Engineers in London on 3 December was presented by Ian Taylor from Shell Global Solutions who spoke about the contribution of lubricants to energy efficiency. He reminded us that the Jost Report in the 1960s estimated that 10% of GNP was spent overcoming friction and wear and around 1.5% of GNP could be saved by optimal selection of lubricants. The majority of the talk demonstrated the significant savings in friction that have proved possible in the automotive industry by the adoption of modern lubricants. These tend to be of much lower viscosity than their predecessors and also have considerable improved viscosity index. Even apparently very small savings in powertrain friction could translate into significant annual savings for operators of large truck fleets. A relatively short section at the end of the talk discussed the contribution of the hydraulic fluid to circuit power consumption. It was suggested, or we were reminded, that the major friction loss in a hydraulic system is pipe friction. Figures presented showed power consumption savings of 25% on a forklift truck used in a cold environment by changing from conventional straight oil to a high viscosity index oil of the same ISO 32 grade. Having made the serious mistake with one test rig I designed of neglecting the hydraulic pipe pressure drop this set me thinking. When I first got involved with hydraulic systems the standard oil seemed to be what would now be an ISO 37 grade. There seems to have been a general trend to adopt ISO 46 fluid. For those not familiar with ISO grading of oils, the number represents the viscosity in cSt at 40°C. My fluid mechanics is a bit rusty, but I think that as a first approximation the friction for laminar flow in a pipe will be roughly proportional to viscosity, so changing from a 46 grade oil to 32 would reduce pipe friction losses by 30%. This is very likely to be a massive saving compared with specifying low friction seals even though the difference will decrease as temperature increases. But, it may introduce some interesting seal development problems with the reduced viscosity. It sounds to me as if it is something that should be looked at seriously with regard to energy saving. Bob Flitney
Sealing Technology
3
and International Shipsuppliers & Services Association (ISSA) references for easy identification.
Contact: Nicholsons Sealing Technologies Ltd, Amos Drive, Greencroft Industrial Park, Stanley, Co. Durham DH9 7YE, UK. Tel: +44 1207 523010, Fax: +44 1207 523011, Email: [email protected], Web: www.nicholsons.co.uk
Contact: James Walker & Co Ltd, Marine Industry Support Team, 1 Millennium Gate, Westmere Drive, Crewe, Cheshire CW1 6AY, UK. Tel: +44 1270 536000, Fax: +44 1270 536100, Email: [email protected], Web: www.jameswalker.biz
Conformal coating coats complex products
Latest diesel needs special gaskets
G
reene, Tweed has introduced an exclusive, proprietary, conformal, PTFE coating capability, Enduro LF10. This coating is intended for use on complex semiconductor components where it can potentially enhance performance. It can be applied to elastomeric, thermoplastic or metal substrates and can help reduce friction and wear. The coating is deposited on component surfaces in a low-temperature environment, allowing the coating of delicate structures, nonplanar surfaces and temperature-sensitive materials. It has good adhesion, high purity and high conformality, thereby reducing the friction or sticking force between two components. Test results indicate that reductions of up to 70% are possible. Coating thickness can vary from 1 to 10 μm depending on whether the material is a solid substrate or flexible such as elastomer.
Contact: Greene, Tweed and Co, 2075 Detwiler Road, PO Box 305, Kulpsville, PA 19443-0305, USA. Tel: +1 215 256 9521, Fax: +1 215 256 0189, Email: [email protected], Web: www.gtweed.com
Guide to marine seals renewed
T
he new edition of James Walker’s sealing guide to marine applications is now available worldwide. This guide describes the wide ranges of products and services supplied to marine operators and shipbuilders, and gives contact details for James Walker’s official marine distributors around the globe. A quick reference chart provides performance data and recommended duties for the most popular products, followed by expanded entries with International Marine Purchasing Association (IMPA)
February 2009
T
he new four-cylinder diesel engines from Mercedes-Benz are intended to set new standards in consumption and exhaust emissions and will rely on gasket technology from Victor Reinz. In addition to the cylinder-head gaskets, a multi-layer steel gasket with wave stopper design, the company is supplying heat shields and special gaskets for the exhaust gas recirculation path in the innovative diesel engine. The new powertrain with two-stage turbocharging and fourth-generation common-rail technology features up to 150 kW, 204 hp, output with a displacement of 2143 cc. The maximum ignition pressure is 200 bar, which has presented the developers with a special challenge: to design a durable and economical cylinder-head gasket that can be used in an entire generation of engines. ‘The cylinder-head gasket for the new OM 651 diesel engine from Mercedes-Benz is a multi-layer steel gasket with stainless-steel cover and bottom and a full-surface fluoroelastomer coating. In combination with the plastic/elastic behavior of the wavestopper, this gasket achieves optimal results in all operating conditions,’ explained project manager Thomas Eberle of Victor Reinz in Neu-Ulm. ‘The engine will be used in the future in many model lines, up to and including the Sprinter. That’s why it was important to us to present a solution from the start that matched the development potential of this diesel engine.’ The exhaust gas recirculation path uses metal beaded gaskets with an elastomer coating. These are partially preassembled at Victor Reinz in Neu-Ulm, Germany, and delivered as a module directly to the assembly line.
Contact: Reinz-Dichtungs-GmbH, Reinzstrasse 3–7, D-89233 Neu-Ulm, Germany. Tel: +49 731 7046 369, Fax: +49 731 7046 400, Email: [email protected], Web: www.reinz.com
BOB’S BIT The Donald Julius Groen Prize Lecture at the Institution of Mechanical Engineers in London on 3 December was presented by Ian Taylor from Shell Global Solutions who spoke about the contribution of lubricants to energy efficiency. He reminded us that the Jost Report in the 1960s estimated that 10% of GNP was spent overcoming friction and wear and around 1.5% of GNP could be saved by optimal selection of lubricants. The majority of the talk demonstrated the significant savings in friction that have proved possible in the automotive industry by the adoption of modern lubricants. These tend to be of much lower viscosity than their predecessors and also have considerable improved viscosity index. Even apparently very small savings in powertrain friction could translate into significant annual savings for operators of large truck fleets. A relatively short section at the end of the talk discussed the contribution of the hydraulic fluid to circuit power consumption. It was suggested, or we were reminded, that the major friction loss in a hydraulic system is pipe friction. Figures presented showed power consumption savings of 25% on a forklift truck used in a cold environment by changing from conventional straight oil to a high viscosity index oil of the same ISO 32 grade. Having made the serious mistake with one test rig I designed of neglecting the hydraulic pipe pressure drop this set me thinking. When I first got involved with hydraulic systems the standard oil seemed to be what would now be an ISO 37 grade. There seems to have been a general trend to adopt ISO 46 fluid. For those not familiar with ISO grading of oils, the number represents the viscosity in cSt at 40°C. My fluid mechanics is a bit rusty, but I think that as a first approximation the friction for laminar flow in a pipe will be roughly proportional to viscosity, so changing from a 46 grade oil to 32 would reduce pipe friction losses by 30%. This is very likely to be a massive saving compared with specifying low friction seals even though the difference will decrease as temperature increases. But, it may introduce some interesting seal development problems with the reduced viscosity. It sounds to me as if it is something that should be looked at seriously with regard to energy saving. Bob Flitney
Sealing Technology
3