Survival of the fittest: Turcon® Stepseal® 2K proves the theory of evolution

Survival of the fittest:  Turcon® Stepseal® 2K proves the theory of evolution

Survival of the fittest: Turcon® Stepseal® 2K proves the theory of evolution

Developing a hydraulic cylinder sealing arrangement with certainty of performance over a wide range of applications has provided a long term engineering challenge. The first breakthrough was in the 70’s when Busak+Shamban, with the Turcon® Stepseal®, revolutionized fluid sealing in cylinder applications. Through on-going research and development, Stepseal® has been further refined and improved, with the latest version, Turcon® Stepseal® 2K, achieving new levels in cylinder sealing performance.

In hydraulic cylinders, used in everything from earth moving machinery to lifting platforms in the toughest working environments, the requirements for sealing are varied and difficult. The seals must keep lubricants within the cylinder chamber and at the same time, keep abrasive media out. The applications are dynamic, often operating at high speeds and significant pressures. A single seal is rarely a good enough solution and in most cases a configuration of seals is required. Typically, a cylinder configuration will comprise of between 3 and 5 different dynamic seal and scraper types.

Turcon® Stepseal® changed the thinking behind the sealing of hydraulic cylinders and after its introduction in 1972, it quickly became a first choice for rod and single acting cylinder sealing for design engineers in major cylinder manufacturers, worldwide.

With Turcon® Stepseal®, it was possible for the first time to arrange several seals, one behind the other to create a static and dynamic sealing arrangement. This double-acting tandem seal configuration was a major advance in fluid power technology, eliminating the build up of disruptive intermediate pressures between seals. This had always been a major problem for engineers and caused loss of operating efficiency, destruction of seals and leakage.

The new seal was developed from a proprietary PTFE based material, Turcon® which offers a low co-efficient of friction and performs over a wide range of operating temperatures. This resulted in greatly improved wear resistance compared with materials previously used.

In the eighties Busak+Shamban introduced Turcon® Stepseal® K which had improved long term sealing performance. However, Busak+Shamban was unwilling to accept that the basic Stepseal® design was the optimal solution for fluid sealing and significant research and development resources were invested in developing its efficiency and application capability. This was partly driven by cylinder manufactures changing the tolerance requirements between the rod and cylinder walls, along with the use of alternative hydraulic fluids and increasing temperatures and pressures. The resulting product was Turcon® Stepseal® 2K.

Turcon® Stepseal® 2K has proved to enhance sealing efficiency. Better extrusion resistance gives superior leakage control and allows larger hardware tolerances, making cylinder production more economic. It also has more uniform, low friction characteristics throughout an extended life and even during the run in period, when friction forces can have the greatest effect on hydraulic seals.

Turcon® Stepseal® 2K is available in nine different compounds, offering unsurpassed sealing security when used with all lubricating and non-lubricating hydraulic fluids, including zinc-free oils and water-based hydraulic fluids. They can also be matched to specific mating surfaces and media. They are suitable for gas applications and seals can be specified to meet the precise degree of extrusion and abrasion tolerance required for an application.

The advantages and benefits to engineers of Turcon® Stepseal® 2K for piston and rod sealing:

  • High static and dynamic sealing effect
  • High extrusion resistance, to suit wide hardware clearances
  • Low friction, increasing performance and working life
  • Stick-slip free starting, no sticking even after shut down
  • High abrasion resistance, maximum operational reliability
  • High resistance to chemicals
  • Simple installation without seal edge deformation
  • Available for rod diameters up to 2600 mm (8' 6'')
  • Available for bore diameters up to 2700 mm (8' 10'')
  • Operational at pressures up to 80 MPa (800 bar, 11600 psi)
  • Operational at speeds up to 15 m/s (49 ft/sec) with reciprocating movements, frequency up to 5 Hz
  • Operating temperatures of -45°C to 200°C (-49°F to 392°F)
  • Suited to mineral oil-based hydraulic fluids, flame retardant hydraulic fluids, environmentally safe hydraulic, fluids (bio-oils), water and other media