Dong-A’s stainless steel corrugated tubes, which is approved by UL(USA), RWTUV(Germany) and is certified as quality products with NET, KS(KSD3628) by the Korean government, are supplied in a roll up to 1,200m and used for water piping system inside buildings. The corrugation pitch is slightly wider to reduce the fluid resistance and thus generate no vibration or noise. It connects with screw-in-field type of fitting with cone packing (NBR, E.P.D.M, Silicon, Graphite).

Product Specification

Helical type fitting (Cone type packing)

For solar heating system, heat-exchanger & drinking water

  • Cross-cut drawing
  • Component & Material

Fitting Assembly Guidelines

For helical type tube and cone type packing (graphite, silicone, EPDM and NBR) fitting

  • Step 1 : Cut Tube
    Cut tube at right angle to tube length using an electric tube cutter.
    Make sure the cut end to be clean and flat.
  • Step 2 : Remove Burr on Tube End
    Use stainless steel brush to remove all burr on tube cut-end.
  • Step 3 : Assemble Nut
    Put nut onto tube.
  • Step 4 : Assemble Clamp Thread Ring
    Put clamp thread ring on tube and screw in clock-wise.
  • Step 5 : Assemble Threaded Cone Packing
    Screw threaded cone packing onto tube until it doesn’t spin anymore. (Do Not screw the packing by force)
  • Step 6 : Tighten Helical Type Clamp Thread Ring and Packing
    Tighten Clamp Thread ring to meet threaded cone packing and fix it.(Double Nut Tightening)
  • Step 7 : Assemble Socket
    Put sealant on tapered thread of brass socket, then screw the socket into piping system or boiler with high torque using a crescent wrench.
  • Step 8 : Assemble Fitting
    Make a whole assembly set of tube, nut, stopper ring, DO NOT use sealant on parallel thread of unino nut!
  • Step 9 : Tighten Nut
    Tighten up the nut and complete the fitting assemble

    NBR & SILICONE & EPDM PACKING / 15A:85kgfㆍcm(8.23Nㆍm), 20A : 120kgfㆍcm(11.83Nㆍm), 25A : 180kgfㆍcm(17.65Nㆍm)
    Graphite Packing /15A : 276kgfㆍcm(27.22Nㆍm), 20A : 360kgfㆍcm(35.50Nㆍm), 25A : 570kgfㆍcm(56.21Nㆍm)