From the Sector

Polyurethane has become an integral part of our daily lives, whether in the construction industry, in leisure activities, in the manufacture of furniture or in numerous other applications. The precision gear pumps from Oerlikon Barmag, which will be presented at this year's UTECH Asia / PU China 2024 in Shanghai, impress with customised solutions for demanding tasks in the chemical industry. They increase the productivity of the often complex manufacturing processes for this wide range of applications.

Oerlikon Barmag pumps handle demanding processes in PUR applications, in the chemical, plastics or paint and lacquers industries. One of the greatest challenges lies in the accurate and reliable metering of toxic or low-viscosity media. With the GM and GA series and the associated components, Oerlikon Barmag presents the optimum equipment for these applications.

GM pump
Pumps in the GM series achieve precise dosing by feeding the flow with low pulsation. The multi-stage GM pump conveys low-viscosity media even under high pressure and the most difficult operating conditions (e.g. 250 bar, 100 mPas). The standard pump for many dosing tasks is the GM series in a square design. With the development of the multi-stage pump, the range of applications for the GM series has been significantly expanded. The round 2-stage GM pump has been specially developed for use in high-pressure technology. It fulfils the special challenge of pumping small flow rates with low viscosities. The pump serves flow rates from 0.05 to 20 ccm/rev and is therefore particularly suitable for the production of PUR moulded parts, block foam, refrigeration unit insulation or sandwich panels.  

GA series
Making products and processes more efficient is a constant challenge for manufacturing companies. This is why Oerlikon Barmag has added the GA series to the GM series especially for the demanding conveying of high-viscosity media. The GA series is available in delivery volumes of 1.25 - 30 cm³/rev (0.6-144 l/h). It is designed for pressures up to 200 bar, for viscosities up to 1,500 Pas and for temperatures up to a maximum of 225°C. With this pump series, Oerlikon Barmag offers customised solutions for process engineering processes where highly accurate and uniform metering is required.

The drum pump
The drum pump from Oerlikon Barmag is specially designed for conveying and dosing highly viscous materials such as adhesives, silicones and other highly viscous materials from drums and other large containers and for pressures of up to 250 bar. One of its special features is not only that it discharges highly viscous materials from the drum, but also that the medium can be dosed directly without an intermediate stop.

The gear pump and drum follower plate are synchronised so that the plate effortlessly reaches the bottom of the container, leaving behind only a very small residual quantity of < 1%. This reduces material costs and has a positive effect on the production process.

Fibres, fabrics, epoxy resins and adhesives from Sicomin have been used by Grand Largue Composites (GLC) to construct the first Class40 racing yacht to feature a significant quantity of flax-fibre reinforcements.
The yacht, called Crosscall, won the Class40 World Championships in June 2022 and is a prototype of the new Lift V2 design by Marc Lombard, one of the leading naval architects in this field.

Class40 is one of the most competitive fleets in yacht racing. The hulls of Class40 yachts must be light in weight, strong and stiff, and durable in the most extreme of conditions. Furthermore, to keep costs down, they cannot be reinforced with carbon fibres. The quality and reliability of the resins used for the infusion and lamination of the hulls are therefore of paramount importance.

Crosscall's cockpit was designed to be effectively non-structural, with the mainsheet, which can generate huge shock loads, supported separately. This would allow the cockpit to be made from a hybrid biaxial fabric comprising 50% flax fibres. Other parts of the boat that incorporate flax fibre include the tunnel, the engine cover, the ballast tanks and the cap. The rest of the boat is reinforced with 100% glass-fibre fabrics.

To help it realise this ambitious design, GLC, an infusion specialist, turned to its long-time material supplier, Sicomin. The hull was moulded and infused in one piece and the deck – including the hybrid flax-fibre cockpit – was also infused as a single part. The internal structure was then laminated into the hull by hand before the hull and deck were finally bonded together.

The infusion resin selected was Sicomin’s SR 1710, a high-modulus structural epoxy. Designed specifically for use in infusion and injection processes, it has exceptionally low viscosity and its low-reactivity hardener makes it suitable for the production of large parts. Composites components made from SR 1710 possess high interlaminar shear-strength and the resin retains its mechanical properties in wet environments.

Sicomin’s low-toxicity SR 8200 was used to laminate the internal structures onto the skin of the hull. Ideal for hand laminating, this system includes a choice of hardeners with a wide range of reactivities, which makes it equally suitable for making large or small parts. The hull and deck were joined together with Sicomin’s Isobond SR 7100, which demonstrates high fatigue strength and is very resistant to microcracking.

An epoxy bonding primer – called Undercoat EP 215 HB+ and supplied by Sicomin’s sister company, Map Yachting – was applied to the moulds first to make demoulding easier. It also serves as an undercoat in the polyurethane exterior paint system that is used instead of gelcoat to protect the epoxy hull from UV damage.

Since the launch of Crosscall, GLC has started building a second Lift V2 Class40 and a third one is now planned, both for which Sicomin will supply the materials.