Ringelflow – GRF-1


For rear surface gating of small-to-medium sized mouldings.

Supports gate diameters up to 1.8 mm and shot weights up to 100 g per insert. The GRF-1 from EXAflow® can be used to process all common non reinforced plastic types. For filled and brittle plastics please contact us beforehand!

  • Ringelflow “Rear surface gating” Features:

    • optimum solution to prevent jetting
    • no gate marks on visible external surfaces and bottom wall
    • ideal for fully rounded edges (e.g,. toys, mouldings with sealing edges and joints)
    • permits internal gating of 2-component mouldings


    For best operating results the Ringelflow insert requires one central ejector and one supporting ejector. Please ensure that all sharp edges in the runner are thoroughly rounded. For reliable demoulding, the diameter of the runner must exceed that of the curved tunnel.



    Contouring of a supporting ejector


    Optimum gate geometry, with edges rounded

  • Installation dimensions “Standard”

    Recommended distances “L” from the injection point to the sprue ejector are given below for the various material groups. 

    The distance “AT” describes the correlated ejector depth.


  • Thermoplastics Elastomers

    When processing thermoplastic elastomers, please observe the following recommendations to ensure reliable de-molding:

    • The distance “L” should decrease with the Shore hardness value.
    • The guide length L*0.8 does not apply to TPEs (or TPU, TPA, respectively). In these applications, a centering cone should be provided as shown in our drawing.
    • This application instruction applies to elastomers in the medium Shore hardness range (uo to 100 Shore A).


  •  Gate sizes

    We would like to make it as easy as possible for you to select the right gate size. To help you make your choice we have plotted a number of charts indicating the range of possible gate sizes for a given molding weight and material. Please take into account the viscosity of the plastic before making your selection. Since the plastics industry is marketing an ever growing number of modified plastics in each category, it is impossible to provide binding data here. Please also note our warranty disclaimer.


  • EXAFLOW Tunnel Gate Inserts

    Catamold 420W-DIN 1.4028-X20Cr13  ( until July 2017,  100Cr6 1.3505 )

    Material designation:
    BASF Catamold 420W – DIN 1.4028 – X20Cr13.
    Hardable stainless steel for production of MIM-Parts.

    Components with high hardness and wear resistance combined with good corrosion resistance against water and steam; e. g. tools, cutting blades, surgical instruments, nozzles, bearings.

    • High wear resistance
    • High corrosion resistance
    • Good machinability
    • Weldable

    C = 0.35 – 0.50 %
    Cr = 12 – 14 %
    Fe = Balance

    Surface quality, roughness Ra 0.8 – 1.3

    Density 7.6 g/cm³
    Carbon content 0.35 – 0.50 %
    Hardness 50 +5 HRC
    Ultimate Tensile Strength Rm      (heat-treated) 1560 mm²