Transcription of EJOT PT Screw
1 The proven fastener for reliablefastening into thermoplasticsEfficiency of PT connections Direct assembly using the ejot PT Screw makes thin-walled and flat designs possible. This leads to material savings and reduced cycle times during injection moulding. Therefore, the quality of the PT joint and the fastening component, translates into a considerable cost saving forcesl Low radial force - equals low radial stressl Large axial component - for optimum material flow into the recessed thread rootDisplacement volumel Larger thread bearing depth - for increased load-carrying capacityl Lower installation torque - because of smaller leverage with the same displacement volumeNotes for the design engineerThe boss geometry should correspond to the de-picted design recommendation.
2 If residual stress, cavities, sink marks, expanded injection cycles etc. due to different wall thicknesses, are possible, the cross-section of the boss has to be changed. The shear stress occurring in the boss during as-sembly may not inadmissibly expand, and for that reason the following sequence should be adhered to:l Decrease external boss diameterl Increase Screw hole diameter. This leads to a decrease of axial load capacity, which can be compensated with l Increased installation depth, to transfer the required strength grades In case of these changes a part evaluation should always be carried out.
3 For materials with high filler content or high internal strength, the use of ejot DELTA PT is recom-mended. The balancing hole is of special importance as it ensures a favourable distribution of edge stress. d1 = nominal of the screwde = d1 + mmdb = hole External S2/3 : x d1 The ejot PT Screw with 30 flank angle and recessed thread The Quality ConnectionEJOT PT Screw K 141,40K 181,80K 121,20K 202,00K 161,60K 252,50K 353,50K 404,00K 505,00K 606,00K 303,00K 222,20K 707,00K 808,00K 101,00K 10010,003 0,303,5 0,384 0,384,5 0,385 0,386 0,387 0,458 0,4510 0,4512 0,5514 0,5516 0,5518 0,5520 0,6522 0,6525 0,6530 0,6535 0,8040 0,8050 0,8060 0,9570 0,9580 0,9590 1,10100 1,10 ejot PT screwLength [mm]Nominal [mm]
4 For more information please contact ejot Hotline, phone +49 2751 529-123, fax 529-98 123, e-mail Subject to technical changes. Chrome VI free coatings: l Zinc-plated, blue passivated l Zinc blue / thick film passivation + EJOSEAL 4Cl Zinc / thick film passivationl ZnFe, ZnNi, clear passivated (with and without sealing / Top Coat)l ZnFe, ZnNi, black passivated (with and without sealing / Top Coat)l Zinc flake coating (with and without sealing / Top Coat) silver and black)l Further coatings upon requestScrew material:l Through hardened steel with material properties PT 10 (WN 1461, part 2)l Other materials upon requestSpecial designs / examples.
5 Special Screw designs are available. Please contact the ejot application engineers to realise individual designs. Upper stepped line = min. length (Counter sunk head production length l + 2 mm)Lower stepped line = max. length Production with partial thread possibleEJOT The Quality ConnectionManufacturing Range of ejot PT Screws
