The EJOT Screw. The proven fastener for thermoplastics. EJOT The Quality Connection

Transcription

1 The EJOT Screw The proven fasener for hermoplasics EJOT The Qualiy Connecion 17

2 - Faseners for Plasics PT is a special fasening elemen for easy and reliable fasening ino hermoplasics 1 2 Imprin Edior: EJOT GmbH & Co. KG Indusrial Faseners Division D Bad Berleburg Germany 3 4 Sandard: maerial properies PT 10 Prin: Druckerei Schlabach GmbH & Co. KG D Erndebrück by EJOT GmbH & Co. KG EJOT, EJOMAT and PT are regisered rademarks of EJOT GmbH & Co. KG. TOR, TOR PUS and AUTOSERT are regisered rade marks of Acumen Inellecual Properies C. All echnical daa may be subjec o echnical improvemens. 22

3 - Faseners for Plasics 1 PT wih 30 flank angle Displacemen volume l larger hread bearing deph - resuls in larger load-carrying capaciy l lower insallaion orques - smaller lever arms bu he same displacemen volume 60 a 1 a 2 30 A 1 A 2 ds 1 b 1 ds 2 dx 1 dx 2 b 2 A = cross-secional area (resuls in he displaced volume over d s ) d s = cener of graviy-diameer A = 4 1 A 2 ds 1 = 3 a 1 a 1 b 1 = a 2 b 2 1,333 a 1 an 30 a 1 ² = an 15 a 2 ² 4 an 30 a 3 = 2 ds 2 = a 1 an 15 a ,468 a 1 1,468 a 1 = a 2 1,952 a 1 30 Radial forces R 1 F Ra 60 F Rad 2 l low radial forces - resul in low radial sress l large axial componen - resuls in opimum maerial flow ino he recessed hread roo R 2 F Axi 1 F Axi 2 F Ra = 0,500 R F Axi 1 = 0,867 R F Rad 2 = 0,259 R F Axi 2 = 0,966 R 3

4 - Faseners for Plasics 2 PT wih opimum pich F l good self-locking of he screw hread l balanced load raio beween plasic and seel h F = shearing sress in he plasic maerial / flexural sress on he screw hread P = hread pich A = shearing diameer = π P W = resising orque of he hread roo = h² d K π = an² α ( - d K )² d K π 2 ד B = shearing fracure sress of he plasic maerial σ B = bending fracure sress of he screw maerial = ד B σ B = F A W M B ד B = 2 an² 1 α (d - d ) d 2 1 K K σ B p P 1/2 ( - d K ) 1/2 a d K 3 PT wih recessed hread roo maerial flow hole Ø hread core diameer Opimum maerial flow during hread-cuing l low radial sress l no maerial jam in he core area l no maerial sress hrough plasicisaion l increased load-carrying capaciy and bes possible resisance agains relaxaion wih opimum boss design Diagram of he maerial flow in he recessed hread roo 4

5 - Faseners for Plasics Microome secion in differen maerials 4 Sandard: maerial properies PT 10 Due o heir geomery, maerial and he producion process, PT Screws offer ousanding safey agains hydrogen induced, delayed brile fracure. For increased demands on corrosion proecion, he PT Screw is also available in A2 or A4 sainless seel. Economic efficiency of PT joins PT joins faciliae he design of hin-walled fla srucures. The resul are maerial saving and cycle ime reducion during injecion moulding. If he overall join coss of a componen are examined, considerable cos saving poenials can be realised wih he PT join. Comparison of microsecions: shee meal screw (lef) and PT (righ) 5

6 - Faseners for Plasics Boss design for EJOT PT Screws The precondiion for a reliable screw join is he funcional design of he componens. S Based on laboraory rials wih models, he following design engineering recommendaions were esablished (see char on he righ). Deviaion from hese recommendaions migh be necessary in pracice. Possible reasons for his are: Sink marks Boss geomery for convenional fasening elemens S l processing condiions of he maerial l design of he injecion moulding ools l disance from he injecion poin l he formaion of flow lines a he convergence of maerial flows l local exures caused by addiives and fillings l maerials wih he same descripion are ofen composed differenly, for example in erms of he proporion of virgin maerial and reclaimed maerial 2/3 S For ha reason roaion speed dependen conrol insallaions should be carried-ou. For his purpose EJOT operaes is own applicaion laboraory, he EJOT APPITEC. Boss geomery for EJOT PT joins exernal Ø d e S Noes for he design engineer The boss geomery should correspond o he illusraed design recommendaion. If inernal sress, caviies, sink marks, expanded injecion cycles ec. have o be feared, due o differen wall hicknesses, he ube cross-secion has o be changed from he following recommendaion. The shear sress occurring in he boss during he assembly may no inadmissibly expand, and for ha reason he following sequence should be adhered o: 0,3 : 0,5 x i 2/3 S d b = hole Ø l decrease he exernal boss diameer l increase he screw hole diameer. This leads o a decline of he axial load carrying capaciy, which can be compensaed by l increasing he insallaion deph in order o ransfer he required srengh values. S Wih hese changes a par evaluaion should be carried-ou in all cases. = nominal Ø of he screw d e = + 0,2 mm The balancing hole is of special imporance as i ensures a favourable disribuion of edge sress. 6

7 - Faseners for Plasics Design recommendaions for EJOT PT Screws Maerial Hole Ø d b Exernal Ø d A Insallaion Deph i ABS 0,80 x d 2,00 x d 2,00 x d ABS PC Blend 0,80 x d 2,00 x d 2,00 x d ASA 0,78 x d 2,00 x d 2,00 x d PA 4.6 0,73 x,85 x,80 x d PA 6 0,75 x,85 x,70 x d PA 6.6 0,75 x,85 x,70 x d PBT 0,75 x,85 x,70 x d PE - D 0,70 x d 2,00 x d 2,00 x d PE - HD 0,75 x,80 x,80 x d PET 0,75 x,85 x,70 x d PET - GF 30 0,80 x,80 x,70 x d POM 0,75 x,95 x d 2,00 x d POM - GF 30 0,80 x,95 x d 2,00 x d PP 0,70 x d 2,00 x d 2,00 x d PP - GF 30 0,72 x d 2,00 x d 2,00 x d PP - TV 20 0,72 x d 2,00 x d 2,00 x d PS 0,80 x d 2,00 x d 2,00 x d PVC (har) 0,80 x d 2,00 x d 2,00 x d SAN 0,77 x d 2,00 x,90 x d Use of he EJOT DETA PT for very high srengh maerials wih high orques Maerial PA GF 30 PA 6 - GF 30 PA GF 30 PBT - GF 30 PC PC GF 30 PMMA PPO PEEK PPS Boss design The maximum clamp load is he crierion for he opimal boss design. The favourable hole diameer is usually a he raio: d b = 0,8 x For maerials wih high filler conen or high inernal srengh, he opimum hole diameer can be increased up o d b = 0,88 x. You can find more informaion abou his opic in he brochure: The EJOT DETA PT Screw 7

8 - Faseners for Plasics Noes on he assembly echnique 4,0 3,5 3,0 T S The following char shows he dependence of he insallaion and sripping orques on he screw hole diameer wih he example of an EJOT PT Screw K 40 in PA6 GF 30. Average values of he es resuls are chared. Torque [Nm] 2,5 2,0 1,5 1,0 0,5 T i opimum diameer: 3.2 mm In order o preven sress cracks or relaxaion he smalles possible axial load should be argeed. The mos favourable erms for his arise over he hole diameer, where he raio M s min / M i max reaches he highes value. 0,0 2,9 3,0 3,1 3,2 3,3 3,4 3,5 3,6 3,7 Hole diameer d b [mm] Deerminaion of he opimum hole diameer Furhermore a reliable assembly is only guaraneed if he scaer range of he expeced ighening orques lies clearly beween he limi values of he insallaion and sripping orques The following values resul from he he es: Opimum screw hole diameer d b op = 3,2 mm Insallaion orque (average value) M i = 0,79 Nm Sripping orque (average value) M s = 3,37 Nm For he direc assembly of plasics, a large variaion of he insallaion and sripping orque is usually noiced, which is caused by geomeric influences or varying exure of he maerial. For his reason he saisical view of he assembly process is necessary. Maerial: PA6 GF30, insallaion deph = 6 mm Screw: EJOT PT K 40 x 10 WN Torque curve (T ) Torque curve (T s ) 3 6 Torque [Nm] Sripping Desrucion of he plasic hread 1 0,0 0,2 0,4 0,6 0,8 1,0 Time [sec] Example curve PT join 1,2 Connecing surface Screw head connecing o he surface Assembly sar 8

9 - Faseners for Plasics Tighening orques and repeaabiliy Excessively high clamp loads can cause relaxaion or sress cracks depending on he kind of plasic. For ha reason he ighening orque has o be kep as low as possible. In order o guaranee reliable screw joins and rouble-free insallaions, a maximum of possible influences should be deermined. For his reason EJOT has a modern es laboraory (APPITEC), in order o deermine he opimum fasening parameers for you. Please conac he EJOT holine: phone: (02751) , holine@ejo.de 3,0 2,5 T S Torque [Nm] 2,0 1,5 1,0 T i Recommended speed range ,5 0, No-load speed n 0 [min -1 ] Influence of he driver roaion speed Maerial: ABS, insallaion deph = 8 mm Screw: EJOT PT K 40 x 16 WN 1451 The screwdriver speed should be max. 500 min -1, in order o preven damage of he plasic maerial and o enable a process reliable insallaion. The resuling ighening orque should be esed wih regards o he repea accuracy of he assembly ool. Torque [Nm] 4,0 3,5 3,0 2,5 2,0 1,5 1,0 T s min = 3,01 Nm T 4,0 3,5 3,0 2,5 2,0 1,5 1,0 Wih he limiing values T i max und T s min he ighening orque T can be deermined wih he following formula: T = 0,5 (0,5 T s min + 1,5 T i max) = 1,51 Nm 0,5 T i max = 1,01 Nm 0,5 0,0 0,0 Deerminaion of he ighening orque Maerial: PA6 GF 30 Hole diameer: 3,2 mm Screw: EJOT PT K 40 x 10 WN 1442 Insallaion deph: 6,0 mm 9

10 * D A S K K D ca D A ~f c - Faseners for Plasics WN 1451 WN 1452 WN 1453 WN 1423 D A Nominal Ø Exernal hread Ø Thread core Ø Thread pich Thread run-ou max Sandard > Shorened < K30 K 35 K 40 K 50 K 60 K 70 K 80 K 100 d1 3,0 3,5 4,0 5,0 6,0 7,0 8,0 10,0 d2 1,66 1,91 2,17 2,68 3,19 3,7 4,21 5,23 P 1,34 1,57 1,79 2,24 2,69 3,14 3,59 4,49 3 d1 3,0 3,5 4,0 5,0 6,0 7,0 8,0 10,0 3 d1 1,5 1,8 2,0 2,5 3,0 3,5 4,0 5,0 WN1451 Head Ø D 6,0 7,0 8,0 10,0 12,0 14,0 16,0 20,0 K 2,1 2,4 2,6 3,3 3,6 4,2 4,8 5,5 T10 T 10 T 20 T 20 T 25 T 30 T 40 T40 A max. 2,80 2,80 3,95 3,95 4,50 5,60 6,75 6,75 Deph min. 1,00 1,10 1,25 1,40 1,60 2,00 2,70 2,70 max. 1,30 1,40 1,70 1,80 2,00 2,40 3,20 3,20 Washer hickness S 0,60 0,70 0,80 1,00 1,20 1,40 1,60 2,00 * WN1452 Head Ø D 5,6 6,9 7,5 8,2 10,8 12,5 14,0 16,0 K 2,1 2,3 2,6 2,9 3,8 4,4 5,0 6,0 T10 T10 T20 T20 T25 T30 T40 T40 A max. 2,80 2,80 3,95 3,95 4,50 5,60 6,75 6,75 Deph min. 1,00 1,10 1,25 1,40 1,60 2,00 2,40 2,70 max. 1,30 1,40 1,70 1,80 2,00 2,40 2,90 3,20 WN1453 Head Ø D 5,6 6,5 7,5 9,2 11,0 12,5 14,5 14,5 c 0,55 0,55 0,65 0,75 0,85 0,85 0,90 0,90 Crown heigh ~f 0,75 0,90 1,00 1,25 1,00 1,80 2,00 2,00 T10 T 15 T20 T 25 T 30 T 40 T40 T40 A max. 2,80 3,35 3,95 4,50 5,60 6,75 6,75 6,75 Deph min. 1,00 1,20 1,40 1,60 2,00 2,70 2,70 2,70 max. 1,30 1,50 1,80 2,00 2,40 3,20 3,20 3,20 WN1423 Head Ø D 5,5 7,3 8,4 9,3 11,3 13,6 15,8 18,3 c 0,55 0,65 0,70 0,75 0,85 0,90 0,95 1,10 T 8 T 15 T20 T20 T 30 T 40 T40 T50 A max. 2,40 3,35 3,95 3,95 5,60 6,75 6,75 8,95 Deph min. 0,80 1,00 1,25 1,25 1,75 2,25 2,40 2,9 max. 1,00 1,30 1,70 1,70 2,20 2,70 2,90 3,5 10

11 * S K D D K D c - Faseners for Plasics WN 1411 WN 1412 WN 1413 WN 1446 WN 1447 SW D SW K S K Nominal Ø Exernal hread Ø Thread core Ø Thread pich Thread run-ou max Sandard > Shorened < K30 K 35 K 40 K 50 K 60 K 70 K 80 K 100 d1 3,0 3,5 4,0 5,0 6,0 7,0 8,0 10 d2 1,66 1,91 2,17 2,68 3,19 3,7 4,21 5,23 P 1,34 1,57 1,79 2,24 2,69 3,14 3,59 4,49 3 d1 3,0 3,5 4,0 5,0 6,0 7,0 8, d1 1,5 1,8 2,0 2,5 3,0 3,5 4,0 5,0 WN1411 Head Ø D 6,0 7,0 8,0 10,0 12,0 14,0 K 2,1 2,4 2,5 3,2 4,0 4,6 Washer hickness S 0,7 0,8 0,9 1,1 1,3 1,5 H cross Widh / size ~m 2,9/1 3,5/2 4,2/2 4,8/2 6,4/3 7,0/3 min. 1,15 1,07 1,33 1,98 2,24 2,84 recess (A) Deph max. 1,61 1,70 1,96 2,61 2,90 3,50 Z cross Widh / size ~m 2,8/1 3,8/2 4,1/2 4,7/2 6,3/3 7,0/3 min. 1,26 1,08 1,40 2,01 2,27 2,91 recess (B) Deph max. 1,51 1,54 1,86 2,47 2,73 3,37 WN1412 Head Ø D 5,3 6,1 7,0 8,8 10,5 12,3 K 2,0 2,5 2,7 3,4 4,0 4,5 H cross Widh / size ~m 2,9/1 4,0/2 4,3/2 4,9/2 6,5/3 7,1/3 min. 1,19 1,23 1,51 2,12 2,44 3,00 recess (A) Deph max. 1,65 1,86 2,14 2,75 3,10 3,66 Z cross Widh / size ~m 2,9/1 3,9/2 4,3/2 4,9/2 6,6/3 7,1/3 min. 1,36 1,26 1,62 2,23 2,57 3,14 recess (B) Deph max. 1,61 1,72 2,08 2,67 3,03 3,61 WN1413 Head Ø D 5,5 7,3 8,4 9,3 11,3 13,6 c 0,55 0,65 0,70 0,75 0,85 0,90 H cross Widh / size ~m 2,7/1 3,9/2 4,2/2 4,6/2 5,2/2 6,9/3 min. 1,10 1,33 1,59 2,04 2,59 3,02 recess (A) Deph max. 1,56 1,96 2,22 2,67 3,22 3,68 Z cross Widh / size ~m 2,7/1 4,0/2 4,2/2 4,6/2 5,1/2 6,8/3 min. 1,20 1,47 1,70 2,06 2,60 3,01 recess (B) Deph max. 1,45 1,93 2,16 2,52 3,06 3,47 WN1446 Wrench size A/F 5,0 5,5 7,0 8,0 10,0 10,0 13,0 13,0 K 1,5 2,3 2,3 3,0 3,5 4,8 5,3 5,8 WN1447 Wrench size A/F 5,0 5,5 5,5 7,0 8,0 8,0 10,0 13,0 K 2,3 2,8 2,8 3,5 4,2 5,0 6,0 7,0 Washer Ø D 6,5 7,0 8,0 10,0 12,0 14,0 16,0 18,0 Washer hickness S 0,6 0,7 0,8 0,8 1,0 1,2 1,2 1,5 * 11

12 - Faseners for Plasics EJOT Micro Screws Nominal Ø Exernal hread Ø Thread core Ø Thread pich Thread run-ou max Sandard > Shorened < K 12 K 14 K 16 K 18 K 20 K 22 K 25 d1 1,2 1,4 1,6 1,8 2,0 2,2 2,5 d2 0,74 0,84 0,92 1,04 1,15 1,25 1,40 P 0,53 0,62 0,67 0,80 0,89 0,98 1,12 3 d1 1,2 1,4 1,6 1,8 2,0 2,2 2,5 3 d1 0,6 0,7 0,8 0,9 1,0 1,1 1,3 WN1411 Head Ø D 4,0 4,4 5,0 K 1,4 1,6 1,8 Washer hickness S 0,5 0,5 0,6 H cross Widh / size ~m 2,3/1 2,4/1 2,6/1 min. 0,51 0,68 0,82 recess (A) Deph max. 0,97 1,14 1,28 Z cross Widh / size ~m 2,4/1 2,5/1 2,6/1 min. 0,73 0,86 1,01 recess (B) Deph max. 0,98 1,11 1,26 C cross Widh / size ~m min. recess Deph max. WN1412 Head Ø D 2,2 2,4 2,6 3,2 3,5 3,9 4,4 K 0,9 1,0 1,1 1,2 1,4 1,5 1,7 H cross Widh / size ~m 1,4/0 1,6/0 1,6/0 1,8/0 2,3/1 2,4/1 2,6/1 min. 0,40 0,47 0,55 0,70 0,64 0,74 0,92 recess (A) Deph max. 0,60 0,77 0,85 1,00 1,10 1,20 1,38 Z cross Widh / size ~m 1,7/0 1,8/0 2,4/1 2,4/1 2,6/1 min. 0,55 0,70 0,82 0,92 1,08 recess (B) Deph max. 0,80 0,95 1,07 1,17 1,33 C cross Widh / size ~m 1,5/0 1,6/0 1,6/0 min. 0,50 0,55 0,55 recess Deph max. 0,75 0,85 0,85 WN1413 Head Ø D 3,0 3,8* 3,8* 4,7 c 0,3 0,35 0,35 0,55 H cross Widh / size ~m 1,6/0 2,35/1 2,35/1 2,6/1 min. 0,55 0,95 0,95 0,97 recess (A) Deph max. 0,85 1,25 1,25 1,43 Z cross Widh / size ~m 1,6/0 2,2/1 2,2/1 2,6/1 min. 0,56 0,92 0,92 1,09 recess (B) Deph max. 0,81 1,17 1,17 1,34 C cross Widh / size ~m min. recess Deph max. WN1451 Head Ø D 4,0 4,5 5,0 K 1,3 1,4 1,5 6 IP 6 IP 6 IP A max. 1,75 1,75 1,75 Deph min. 0,50 0,65 0,65 max. 0,65 0,80 0,80 Washer hickness S 0,40 0,50 0,50 WN1452 Head Ø D 2,4 2,8 3,2 3,6 3,6 4,0 4,2 K 0,9 1,0 1,1 1,3 1,5 1,4 1,6 3 IP 5 IP 6 IP 6 IP 6 IP 6 IP 8 IP A max. 1,20 1,45 1,75 1,75 1,75 1,75 2,40 Deph min. 0,40 0,50 0,50 0,50 0,65 0,65 0,70 max. 0,55 0,65 0,65 0,65 0,80 0,80 0,90 WN1423 Head Ø D 3,4 3,8 3,8 4,7 c 0,35 0,35 0,35 0,55 6 IP 6 IP 6 IP 8 IP A max. 1,75 1,75 1,75 2,40 Deph min. 0,50 0,50 0,65 0,70 max. 0,65 0,65 0,80 0,90 12

13 - Faseners for Plasics Special designs / examples Special designs are available. Please conac he EJOT applicaion engineers o realise your individual design. Chrome VI-free plaings l zinc plaed, blue passivaed l zinc-plaed, blue / hick film passivaed + EJOSEA l zinc-plaed, hick film passivaed l ZnFe, ZnNi, ransparen passivaed (wih and wihou sealing / Top Coas) l ZnFe, ZnNi, black passivaed (wih and wihou sealing / Top Coas) l zinc flake coaing (wih or wihou sealing / Top Coas in silver and black) l oher surface coaings upon reques Maerial l hrough hardened seel wih maerial properies PT 10 (WN 1461, par 2) l oher maerials upon reques For furher informaion: EJOT Holine phone fax holine@ejo.de Manufacuring range of he EJOT PT Screws EJOT PT Screw engh [mm] Nominal Ø [mm] 3 ± 0,30 3,5 ± 0,38 4 ± 0,38 4,5 ± 0,38 5 ± 0,38 6 ± 0,38 7 ± 0,45 8 ± 0,45 10 ± 0,45 12 ± 0,55 14 ± 0,55 16 ± 0,55 18 ± 0,55 20 ± 0,65 22 ± 0,65 25 ± 0,65 30 ± 0,65 35 ± 0,80 40 ± 0,80 50 ± 0,80 60 ± 0,95 70 ± 0,95 80 ± 0,95 90 ± 1, ± 1,10 K 10 1,00 K 12 1,20 K 14 1,40 K 16 1,60 K 18 1,80 K 20 2,00 K 22 2,20 K 25 2,50 K 30 3,00 K 35 3,50 K 40 4,00 K 50 5,00 K 60 6,00 K 70 7,00 K 80 8,00 K ,00 Upper sepped line = min. lengh (Couner sunk head producion lengh l + 2 mm) ower sepped line = max. lengh Ferigung nur mi Teilgewinde möglich 13

14 Your sysem parner Tes bench a EJOT APPITEC Design Consulaion A major consideraion of oday s produc manufacure is he basic need o be cos compeiive. The cos srucure of he manufacured produc is significanly influenced by he design engineering. Generally speaking, he developmen of a produc, which represens abou 10% of he overall coss, deermines abou 70% of he coss for he final produc. Here he cos responsibiliy of he design engineer becomes eviden, because he should hink abou he adequae fasening echnology already during he produc concepion sage. I is known ha an aleraion of he par during he producion sage is much more expensive han an opimisaion during he design concepion sage. To assis our cusomers in his process EJOT offers suppor during he design sage by comprehensive applicaion engineering services. These services provide accurae informaion on produc performance and resul in design recommendaions ha can be used safely on he produc line. Consequen Applicaion Engineering The daily work wih our cusomers and heir applicaion queries grealy influences our undersanding of fasening echnology and opens up possibiliies for innovaion. This way we consequenly improve our producs o mee cusomer demands and needs. In addiion o highly-qualified engineers and applicaion engineering consulans our applicaion laboraory, he EJOT APPITEC, is a your disposiion. Here we carry ou a series of ess on he cusomer componens and also develop new fasening soluions. Our knowledge is passed on o our cusomers and his way suppors heir effor owards more raional fasening and assembly. Deailed es repors, echnical advice on sie, acknowledged seminars and echnical publicaions show our Know- How. Training Tes repor 14

15 ogisic and Daa Exchange I is our aim o keep procuremen and warehousing coss as low as possible by simulaneously offering produc availabiliy and qualiy. Wih respec o simplified procuring processes, EJOT offers a variey of cos reducing procedures and services. The coninued analysis of our cusomers demands and advanced logisics procedures lead o high availabiliy of our producs. Your sysem parner Qualiy for Auomaed Assembly Successful assembly auomaion means high uilisaion of he equipmen. The qualiy of he screw used for fasening can be a decisive facor for machine upimes and a more efficien assembly process. Sandard qualiy is no sufficien anymore. The grade of puriy offered by EJOMAT Qualiy is 10 imes higher han he usual sandard qualiy which means increased availabiliy of assembly machines and decreased assembly coss: EJOMAT Qualiy ha pays for iself. EJOT Sales Organisaion In addiion o EJOT companies hroughou Europe a growing number of icensees in Norh & Souh America and Asia ensure he global availabiliy of producs and local suppor. Conac deails can be found on our homepage Modern PPS-sysems lead o high accuracy in supply and shor hrough pu imes EJOMAT for fully-auomaed assembly 15

16 EJOT GmbH & Co. KG Indusrial Faseners Division Im Herrengaren 1 D Bad Berleburg Posfach D Bad Berleburg phone fax indusrie@ejo.de Inerne: EJOT The Qualiy Connecion 182/1/