Leak-proof connections under adverse conditions

50 | Special Fluid Technology tionally secured by the special-purpose Stauff Viton sea- ling ring. In the first generation, the sealing ring consis- ted of two materials, namely the metallic adapter ring and a fixed elastomeric seal. The Stauff Viton sealing ring has been used since 2020, and is considerably less expensive as it is made of only a singlematerial. This cost saving is appreciable for OEMs, such as Damen Shipyards, which fabricate large num- bers of hydraulic tube connections. Safe thanks to superior tear resistance The crucial argument for using Stauff FormEvo, particu- larly in safety-critical fields – including shipbuilding – has undoubtedly been its excellent tear strength, which offers considerable safety benefits under extreme con- ditions, such as strong pressure surges and vibrating loads. A further argument in favour of Stauff Form Evo is its DNV accreditation. Stauff Form Evo is also impressive in terms of corro- sion resistance, as all components are supplied as stan- dard with a high-grade Stauff zinc/nickel coating. This coating provides reliable corrosion protection with over 1,200 hours of resistance to red rust or base metal corro- Up to now, Damen has favoured welding for tube connections. However, now the shipyard has swit- ched over to the Stauff Form Evo forming system. Various Stauff connection and fastening technology pro- ducts are used at the Damen Shipyard Group’s Hardinxveld site. Source: Damen Source: Damen sion in the salt spray test chamber (in accordance with DIN EN ISO 9227). The requirements defined in the VDMA standard sheet 24576 for tube connections are still exceeded for the highest K5 corrosion protection class even after transportation, processing and installation of the com- ponents. Damen considers the broad temperature range of -35 °C to 200 °C as an added bonus, as is the fact that Stauff Form Evo can be used within pressure ranges of up to 800 bar in the Heavy Series (with a four-fold safety factor). Tube preparation workflows have been greatly simpli- fied since the Hardinxveld tube experts switched over fromwelding to forming. Marcel De Bruin: “Previously we had to prepare, weld, clean, X-ray and possibly rework the tubes, and then zinc-plate or paint them. Personnel outlay, processing times and costs were high. We now simplymeasure the tube, saw it and deburr it. It is then bent and formed and can be directly installed.” Saving time and money Eight piping experts prepare around 8,000 hydraulic tubes for installation each year with the Stauff FormEvo machine, which is located inHardinxveld. Themachine is thus used for around 16,000 connection processes with tubes from eight to 42 mm in diameter – of which around 95% are steel tubes and 5% stainless steel tubes. This “mixed use” is yet another benefit of Stauff Form Evo. Mark Kramer, Sales at JBHydraulics: “The old Stauff Form system required different seals for steel and stain- less steel tubes. The new Viton sealing ring works with both materials. The forming tools can also be used for the two materials. This saves time when it comes to changing tools.” The operators are highly satisfied with the system and are even planning ahead. Marcel De Bruin: “We are currently considering pur- chasing another Stauff Form Evo machine.” (häu) Kanban-based delivery The Netherlands-based hydraulics wholesaler JB Hydraulics deli- vers the Stauff Form Evo components to the Hardinxveld shipyard using the Kanban method, as well as the cutting ring fittings used by Damen to connect fuel and lubricant lines. Marcel De Bruin, Piping Manager at Damen Piping at the Hardinxveld site, adds: “The Kanban service is really practical. We always have the connec- tors we need on site, almost automatically.” INFO