|SPETORING® R-Double Cone Seal|
SPETORING® R Double Cone Seals are provided commonly to highest duty pressure vessels equipment (mostly in chemical processing industry). Typical working pressure 50-350 bars and typical temperature up to 400°C, diameter between 500 to 3000mm. They are self-energized gasket which construction details need to be designed essentially by the device designers. Although they look similar to octagonal RTJ the rule of sealing effect ot the joint is different than RTJ.
How it works? After being acted by internal pressure, double cone seal expands outward and the contact pressure between gasket and flange increases substancially. Normally at the conical surfaces of the SPETORING® R Double Cone Seal layers of soft metal are installed – mostly silver, soft iron, aluminium or cooper with thicknes of 0,5÷1mm. To increase friction conical surfaces of gasket (which contact with flange surfaces) are often additionally machined: either with 2-5 groovs (0,5÷1mm deep) or given convex shape.
Please note that during fitting the radial gap of 0,05mm for every 100mm of diameter of non-assembled seal should be precisely controlled and at the cylindrical, supporting surface of cover should be machined longitudinal grooves; Hence internal pressure act on the cylindrical internal surface of the gasket.
|Layers for Double Cone Seal|
|SPETORING® R-Delta Seal|
SPETORING® R Delta seal is used for pressure vessel covers. It requires a special flange construction with triangular grooves. How it works? The total depth of grooves is a little bit lower than the hight of gasket in the non-installed state. When tighten up the bolts, the cover gently approaches to the shell flange. After starting the pressure the delta seal bends cross section and contacts linearly in bottoms of grove under high contact pressure. As being acted by internal pressure the delta seal bends even more outwards, and the conical surface of seal tightly contacts the conical surfaces on seal grooves. Please note the high machining accuracy and high precision of any surfaces of SPETORING® R-Delta style joints are required!
Also the edges of the delta seal can imprint bottoms of grooves, so — after disassembling — machining of grooves and — probably — new gasket with new (increased) hight will be required.
Application range of delta seal is up to 2000mm of diameter temperature mostly lower than 400°C and pressure lower than 400 bars.
|SPETORING® R-Bredtschneider Seal (Wedge Seal)|
SPETORING® R-Bredtschneider Seal is another solution used to secure tightness in to self — tightening covers. The construction of seat for this kind of seal is very special and need perfect geometry of conical contact surface both: at cover and shell. For positioning and blocking of gasket special segment ring is needed. The pretightening force of bolt (must be strain bolts in cover and in segmented ring) is very low. The sealing action is coming from internal pressure acting on cover. This working (medium) pressure is multiplicated into contact pressure of SPETORING® R in two ways:
Normally Bredtschneider Seal is manufactured from the material softer than cover and flange material (after installation seal ring is closed almost "hydraulically" from all sides). Please note disadvantage can be observed, when material of ring is too soft and extrude in gaps between cover and shell. In can cause the disassambly difficulties.
Good sealing properties can be kept even when the temperature and pressure fluctuate. The typical application range for SPETORING® R —Bredtschneider Seal are: pressure to 400 bars, temperature 350°C and diameter 1300mm.
In praxis geometry of this kind of seals can vary: cross section may by symmetrical or not and face surface can be perpendicular to axe of shell or not.