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請教一下什麼是螺釘有接觸壓力跟沒有接觸壓力??
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2 P, o: L$ |3 e/ l# f- W17 Electrical connections and mechanical fixings
3 I8 x' m6 F1 D3 M; X' Q9 w17.1 DE Screw TERMINALS providing electrical contact and screw fixings which during the life of the
( @2 n, Q- S5 X, Japparatus will be loosened and tightened several times shall have adequate strength.
! j. v4 \7 R, q- G4 H* KScrews exerting contact pressure and screws with a nominal diameter less than 3 mm which form part of
- L3 J2 r5 }, J- @1 |the above-mentioned screw fixings shall screw into a metal nut or a metal insert.3 j, r: G2 S2 ]+ ^. }9 a& B
However, screws having a nominal diameter less than 3 mm, which do not exert contact pressure, need
( X% v2 m& _1 p" X* K3 Z# E8 E& ?, Vnot be screwed into metal, provided that the screw fixing withstands the torque specified in table 20 for
7 v: p( [) {: R4 I# `9 ?screws of 3 mm diameter. |
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