- Email: [email protected]
Spring-energised seal extends service life of syringe pumps
NEWS
Kaco engineers reduced-friction sealing system
BOB’S BIT
I
K
aco GmbH + Co Kg has engineered a friction-reducing sealing system. Called Fred – where the ‘‘F’’ in the acronym stands for friction and ‘‘red’’ for reduced – it is designed to be used in truck engines. The mechanical efficiency of drive-unit components is a point of focus in the development of engines and drive-trains. The company says that it is focusing on ways of further developing the sealing system for its application in vehicles.
Contact: Kaco GmbH + Co Kg, Rosenbergstrasse 22, D-74072 Heilbronn, Germany. Tel: +49 7131 6360, Fax: +49 7131 636386, Web: www.kaco.de.
Wireless unit transmits leak detection data to the desktop
H
alma Water Management is now offering the PermaNet system, a wireless unit that transmits leak detection data, collected from Permalog+ loggers, directly to an office computer via network radio or an SMS repeater. The loggers ‘listen’ for the noise made by water leaking from pipes and when a potential leak is detected they enter an alarm state and transmit a radio signal to indicate a ‘‘leak’’ condition. Loggers can be quickly deployed and used repeatedly, with no disruption to the surrounding area or to the water supply, and the precise location of each logger can be recorded as it is put into the ground by GPS mapping software. Each logger is immersion-tested to IP68, enabling it to operate continuously, even in flooded chambers. They are powered by low-cost, replaceable batteries. The location and leak status of each logger is displayed directly and accurately on a map of the area, with further information available at the click of a button.
Contact: Halma Water Management, Ty Coch House, Llantarnam Park Way, Cwmbran NP44 3AW, UK. Tel: +44 1633 489 479, Fax: +44 1633 877 857, Email: [email protected], Web: www.hwm-water.com.
Editor’s comment: This appears to be aimed predominantly at the management of water mains, but it could be of potential interest to plant operators.
May 2010
The Permalog+ instrument can now transmit leak detection data directly to a desktop computer using the PermaNet wireless system.
Guide helps aerospace engineers specify seals
T
relleborg Sealing Solutions has introduced a new publication on designing sealing systems for aerospace applications. The ‘Aerospace Product Catalog and Engineering Guide’ includes details of services, standards, specially developed materials and industry-specific sealing products, along with guidance on hardware and installation procedures. It incorporates numerous engineering drawings and is designed to be easy-to-use with a lot of practical information, says the company. ‘This is more of an engineering guide than a catalogue,’ commented Torben Andersen, who heads up global aerospace business development. ‘The publication has been a couple of years in the making and involved a large number of our company’s aerospace experts. Seeing the finished version, I think it has been well worth all the hard work and I am sure that it will make the life of aerospace engineers easier when they are specifying seals.’
Contact: Trelleborg Sealing Solutions, Global Marketing & Communications, Handwerkstrasse 5–7, D-70565 Stuttgart, Germany. Tel: +49 711 78640, Fax: +49 711 7864 344, Email: [email protected], Web: www.tss.trelleborg.com.
Spring-energised seal extends service life of syringe pumps
T
relleborg Sealing Solutions has been working with TriContinent Scientific on a way of sealing syringe pumps that avoids premature seal failure and eliminates instrument down time.
f you have not already seen the back page of this issue, we have a news item reporting the publication of a new guide from the European Sealing Association (ESA). This guide, aimed at fault diagnosis – and through that, improved future reliability – of elastomer seals is the result of a collaborative effort by the members of the ESA Elastomer and Polymeric Seals Division that has lasted some two years. It is certainly one of the most thorough guides I have seen and it has benefited from a sensible use of computer-based techniques by being interactive. This makes it easy and convenient to use. A further significant factor is that it is produced by the seal manufacturing industry in an attempt to promote improved seal reliability. The more astute companies realise that if a customer experiences repeated seal problems, the result may be loss of sales to a competitor, but of concern to the whole industry is that it may persuade that customer to investigate an approach or technology that can eliminate seals altogether. The pump industry has experience of this with the seal-less pump debate. There is a thought that perhaps I should be concerned about this new publication – as a competitor for sealing handbooks, courses and the odd bit of consultancy. But, my current experience is that there are enough questions, and requirements for reliability enhancements, to keep plenty of us busy. As we have mentioned before, it is often a requirement for a reliable seal that can prevent a technology progressing. At the time of writing, I am at various stages of involvement with three very different applications where achieving a suitable seal is a considerable stumbling block. These vary from high-value one-off equipment through commercial manufacturing to a low-cost, almost disposable item, which still presents a considerable sealing challenge. Another is a good technical idea that has been around for a long time, but has failed to make much market penetration because it depends on some high-integrity dynamic sealing. And the third is, perhaps, even more challenging, and may well be beyond any sensible, commercial seal’s capability. In this case, it could be a matter of adopting an alternative technology to achieve the required objective using a process that will depend on rather more benign sealing duties. But, if the customer achieves the required objectives, future developments should create further challenges. Bob Flitney
Sealing Technology
3
NEWS Sealing used in syringe pumps can be challenging. Plastic-type plungers made of a variety of materials act as pistons that ride in bores generally made of glass or ceramic. Seals are often incorporated into the tips of the plungers, sometimes resulting in one-piece components. Trelleborg supplies an integrated springenergised seal to syringe pump manufacturer TriContinent Scientific. The two companies have worked together on the development of a novel seal design for a pump platform, to solve a problem for one of TriContinent Scientific’s customers. The final design provides a more consistent sealing force on the sealing lip, resulting in extended seal life and eliminating instrument down time. The seal was failing prematurely because reagents were adhering to a ceramic piston and causing the seals to deteriorate. Using TriContinent Scientific’s own patented seal design, engineers at Trelleborg were able to modify the seal and offer a solution to this problem. This involved an integrated polymer dynamic seal with a HiMod 550 custom-shaped energiser within a custom, ultra-high molecular weight polyethylene (UHMWPE) jacket. HiMod is a glass- fibre reinforced thermoplastic material and avoids any issues associated with the use of a metal energiser.
‘The success of this syringe pump design hinged on finding the perfect seal material and configuration,’ explained Mik Bajka, Engineering Manager, TriContinent Scientific. Contact: Trelleborg Sealing Solutions, Global Marketing & Communications, Handwerkstrasse 5–7, D-70565 Stuttgart, Germany. Tel: +49 711 78640, Fax: +49 711 7864 344, Email: [email protected], Web: www.tss.trelleborg.com.
Low-temperature FKM grades introduced
P
recix Inc has extended its range of speciality grades of fluoroelastomer compounds. The company says that it now has three compounds that are intended for applications involving low temperatures. They are designated -30, -35 and –40 (Solvay). The compound material codes are F119, F122 and F103, respectively. It is also interesting to note that the company provides a cost comparison for the grades. For instance, F103 is 8.5 times the cost of a standard FKM A-type grade.
Contact: Precix Inc, 744 Belleville Avenue, New Bedford, MA 02745, USA. Tel: +1 508 998 4000, Fax: +1 508 998 4100, Email: [email protected], Web: www.precixinc.com.
Heat-resistant sealing materials target automotive applications
N
Trelleborg Sealing Solutions has been working with TriContinent Scientific to develop an integrated spring-energised seal for a syringe pump.
4
Sealing Technology
itrile butadiene rubber (NBR) and polyacrylate rubber (ACM) materials for high-temperature applications have been developed by Freudenberg Dichtungs- und Schwingungstechnik (FDS). They are targeted at automotive applications, such as engines, gears, steering mechanisms and brakes. Optimised use of space, highly efficient engines and increased encapsulation result in higher radiated temperatures and accumulated heat in the engine compartments of cars and commercial vehicles. By modifying NBR and
ACM, Freudenberg has succeeded in enabling these materials, which are widely used and approved for use in the automotive industry, to meet increased temperature requirements. The heat resistance of these materials has been achieved by changing the way in which they are formulated. The focus was on the different fields of application – in engines, gears, steering mechanisms and pneumatic brakes. All of these areas have a number of things in common – namely the fact that the media come in contact with air, ‘oily air’ and different oils containing additives. As illustrated in the paragraphs that follow, the new HT-NBR and HT-ACM sealing materials can be amended to meet the temperature requirements of specific applications. The first example concerns the use of HT-NBR in steering systems and pneumatic brakes. NBR is the classic material for seals that come into contact with oil or oily air. Up until now, seals made from this material only could be used permanently at temperatures up to 110°C. A modification in the formulation means that they now can be used over a broader temperature range. Through the use of nitrosamine-free sulphur cross-linking, which was chosen for reasons of maximum cost-efficiency, the ageing resistance of this material has been optimised for shortterm peak temperatures of up to 125°C. In addition, the new HT-NBR material 75 NBR 233407 still demonstrates elastomeric resilience after being stored for 1008 hours (42 days) at 110°C. A cold-modified compound, 70 NBR 234154, also has been developed. This has a glass transition temperature (Tg) of -50°C (with the Tg calculated by means of differential scanning calorimetry). In the past, ACM materials, which are based on sulphur/soap cross-linking, were not suitable for use at temperatures of up to 175°C – such as those that occur in dualclutch gearboxes. For this reason, Freudenberg developed high-temperature ACM materials (HT-ACM) that now feature amine cross-linking and, consequently, are capable of withstanding these temperatures. These offer not only cost benefits but also clear performance advantages over FKM in those applications where resistance to transmission oils, containing a high proportion of additives, is required. Contact: Freudenberg Dichtungs- und Schwingungstechnik, D-69465 Weinheim, Germany. Tel: +49 6201 803631, Fax: +49 6201 883631, Email: [email protected], Web: www.freudenberg-ds.de.
May 2010
Kaco engineers reduced-friction sealing system
BOB’S BIT
I
K
aco GmbH + Co Kg has engineered a friction-reducing sealing system. Called Fred – where the ‘‘F’’ in the acronym stands for friction and ‘‘red’’ for reduced – it is designed to be used in truck engines. The mechanical efficiency of drive-unit components is a point of focus in the development of engines and drive-trains. The company says that it is focusing on ways of further developing the sealing system for its application in vehicles.
Contact: Kaco GmbH + Co Kg, Rosenbergstrasse 22, D-74072 Heilbronn, Germany. Tel: +49 7131 6360, Fax: +49 7131 636386, Web: www.kaco.de.
Wireless unit transmits leak detection data to the desktop
H
alma Water Management is now offering the PermaNet system, a wireless unit that transmits leak detection data, collected from Permalog+ loggers, directly to an office computer via network radio or an SMS repeater. The loggers ‘listen’ for the noise made by water leaking from pipes and when a potential leak is detected they enter an alarm state and transmit a radio signal to indicate a ‘‘leak’’ condition. Loggers can be quickly deployed and used repeatedly, with no disruption to the surrounding area or to the water supply, and the precise location of each logger can be recorded as it is put into the ground by GPS mapping software. Each logger is immersion-tested to IP68, enabling it to operate continuously, even in flooded chambers. They are powered by low-cost, replaceable batteries. The location and leak status of each logger is displayed directly and accurately on a map of the area, with further information available at the click of a button.
Contact: Halma Water Management, Ty Coch House, Llantarnam Park Way, Cwmbran NP44 3AW, UK. Tel: +44 1633 489 479, Fax: +44 1633 877 857, Email: [email protected], Web: www.hwm-water.com.
Editor’s comment: This appears to be aimed predominantly at the management of water mains, but it could be of potential interest to plant operators.
May 2010
The Permalog+ instrument can now transmit leak detection data directly to a desktop computer using the PermaNet wireless system.
Guide helps aerospace engineers specify seals
T
relleborg Sealing Solutions has introduced a new publication on designing sealing systems for aerospace applications. The ‘Aerospace Product Catalog and Engineering Guide’ includes details of services, standards, specially developed materials and industry-specific sealing products, along with guidance on hardware and installation procedures. It incorporates numerous engineering drawings and is designed to be easy-to-use with a lot of practical information, says the company. ‘This is more of an engineering guide than a catalogue,’ commented Torben Andersen, who heads up global aerospace business development. ‘The publication has been a couple of years in the making and involved a large number of our company’s aerospace experts. Seeing the finished version, I think it has been well worth all the hard work and I am sure that it will make the life of aerospace engineers easier when they are specifying seals.’
Contact: Trelleborg Sealing Solutions, Global Marketing & Communications, Handwerkstrasse 5–7, D-70565 Stuttgart, Germany. Tel: +49 711 78640, Fax: +49 711 7864 344, Email: [email protected], Web: www.tss.trelleborg.com.
Spring-energised seal extends service life of syringe pumps
T
relleborg Sealing Solutions has been working with TriContinent Scientific on a way of sealing syringe pumps that avoids premature seal failure and eliminates instrument down time.
f you have not already seen the back page of this issue, we have a news item reporting the publication of a new guide from the European Sealing Association (ESA). This guide, aimed at fault diagnosis – and through that, improved future reliability – of elastomer seals is the result of a collaborative effort by the members of the ESA Elastomer and Polymeric Seals Division that has lasted some two years. It is certainly one of the most thorough guides I have seen and it has benefited from a sensible use of computer-based techniques by being interactive. This makes it easy and convenient to use. A further significant factor is that it is produced by the seal manufacturing industry in an attempt to promote improved seal reliability. The more astute companies realise that if a customer experiences repeated seal problems, the result may be loss of sales to a competitor, but of concern to the whole industry is that it may persuade that customer to investigate an approach or technology that can eliminate seals altogether. The pump industry has experience of this with the seal-less pump debate. There is a thought that perhaps I should be concerned about this new publication – as a competitor for sealing handbooks, courses and the odd bit of consultancy. But, my current experience is that there are enough questions, and requirements for reliability enhancements, to keep plenty of us busy. As we have mentioned before, it is often a requirement for a reliable seal that can prevent a technology progressing. At the time of writing, I am at various stages of involvement with three very different applications where achieving a suitable seal is a considerable stumbling block. These vary from high-value one-off equipment through commercial manufacturing to a low-cost, almost disposable item, which still presents a considerable sealing challenge. Another is a good technical idea that has been around for a long time, but has failed to make much market penetration because it depends on some high-integrity dynamic sealing. And the third is, perhaps, even more challenging, and may well be beyond any sensible, commercial seal’s capability. In this case, it could be a matter of adopting an alternative technology to achieve the required objective using a process that will depend on rather more benign sealing duties. But, if the customer achieves the required objectives, future developments should create further challenges. Bob Flitney
Sealing Technology
3
NEWS Sealing used in syringe pumps can be challenging. Plastic-type plungers made of a variety of materials act as pistons that ride in bores generally made of glass or ceramic. Seals are often incorporated into the tips of the plungers, sometimes resulting in one-piece components. Trelleborg supplies an integrated springenergised seal to syringe pump manufacturer TriContinent Scientific. The two companies have worked together on the development of a novel seal design for a pump platform, to solve a problem for one of TriContinent Scientific’s customers. The final design provides a more consistent sealing force on the sealing lip, resulting in extended seal life and eliminating instrument down time. The seal was failing prematurely because reagents were adhering to a ceramic piston and causing the seals to deteriorate. Using TriContinent Scientific’s own patented seal design, engineers at Trelleborg were able to modify the seal and offer a solution to this problem. This involved an integrated polymer dynamic seal with a HiMod 550 custom-shaped energiser within a custom, ultra-high molecular weight polyethylene (UHMWPE) jacket. HiMod is a glass- fibre reinforced thermoplastic material and avoids any issues associated with the use of a metal energiser.
‘The success of this syringe pump design hinged on finding the perfect seal material and configuration,’ explained Mik Bajka, Engineering Manager, TriContinent Scientific. Contact: Trelleborg Sealing Solutions, Global Marketing & Communications, Handwerkstrasse 5–7, D-70565 Stuttgart, Germany. Tel: +49 711 78640, Fax: +49 711 7864 344, Email: [email protected], Web: www.tss.trelleborg.com.
Low-temperature FKM grades introduced
P
recix Inc has extended its range of speciality grades of fluoroelastomer compounds. The company says that it now has three compounds that are intended for applications involving low temperatures. They are designated -30, -35 and –40 (Solvay). The compound material codes are F119, F122 and F103, respectively. It is also interesting to note that the company provides a cost comparison for the grades. For instance, F103 is 8.5 times the cost of a standard FKM A-type grade.
Contact: Precix Inc, 744 Belleville Avenue, New Bedford, MA 02745, USA. Tel: +1 508 998 4000, Fax: +1 508 998 4100, Email: [email protected], Web: www.precixinc.com.
Heat-resistant sealing materials target automotive applications
N
Trelleborg Sealing Solutions has been working with TriContinent Scientific to develop an integrated spring-energised seal for a syringe pump.
4
Sealing Technology
itrile butadiene rubber (NBR) and polyacrylate rubber (ACM) materials for high-temperature applications have been developed by Freudenberg Dichtungs- und Schwingungstechnik (FDS). They are targeted at automotive applications, such as engines, gears, steering mechanisms and brakes. Optimised use of space, highly efficient engines and increased encapsulation result in higher radiated temperatures and accumulated heat in the engine compartments of cars and commercial vehicles. By modifying NBR and
ACM, Freudenberg has succeeded in enabling these materials, which are widely used and approved for use in the automotive industry, to meet increased temperature requirements. The heat resistance of these materials has been achieved by changing the way in which they are formulated. The focus was on the different fields of application – in engines, gears, steering mechanisms and pneumatic brakes. All of these areas have a number of things in common – namely the fact that the media come in contact with air, ‘oily air’ and different oils containing additives. As illustrated in the paragraphs that follow, the new HT-NBR and HT-ACM sealing materials can be amended to meet the temperature requirements of specific applications. The first example concerns the use of HT-NBR in steering systems and pneumatic brakes. NBR is the classic material for seals that come into contact with oil or oily air. Up until now, seals made from this material only could be used permanently at temperatures up to 110°C. A modification in the formulation means that they now can be used over a broader temperature range. Through the use of nitrosamine-free sulphur cross-linking, which was chosen for reasons of maximum cost-efficiency, the ageing resistance of this material has been optimised for shortterm peak temperatures of up to 125°C. In addition, the new HT-NBR material 75 NBR 233407 still demonstrates elastomeric resilience after being stored for 1008 hours (42 days) at 110°C. A cold-modified compound, 70 NBR 234154, also has been developed. This has a glass transition temperature (Tg) of -50°C (with the Tg calculated by means of differential scanning calorimetry). In the past, ACM materials, which are based on sulphur/soap cross-linking, were not suitable for use at temperatures of up to 175°C – such as those that occur in dualclutch gearboxes. For this reason, Freudenberg developed high-temperature ACM materials (HT-ACM) that now feature amine cross-linking and, consequently, are capable of withstanding these temperatures. These offer not only cost benefits but also clear performance advantages over FKM in those applications where resistance to transmission oils, containing a high proportion of additives, is required. Contact: Freudenberg Dichtungs- und Schwingungstechnik, D-69465 Weinheim, Germany. Tel: +49 6201 803631, Fax: +49 6201 883631, Email: [email protected], Web: www.freudenberg-ds.de.
May 2010