Treatment of Firmly Screw-Connected Contact Surfaces
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Check that the heat shrinkable sleeve is not in contact with lubricant (swelling) when handling the bars insulated by heat-shrinkable sleeves.
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Check that the contact areas coated with lubricant KL are not touched.
Follow the below steps for treatment of firmly screw-connected contact surfaces:
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Check that the contact areas are subjected to preliminary treatment before screw fastening (see Table).
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Immediately after the preliminary treatment, coat contact surfaces completely with a thin and uniform film of lubricant KL.
|
Material of contact surfaces |
Pre-treatment |
|---|---|
|
Silver-plated contact surfaces |
Clean(1) |
|
Nickel-plated contact surfaces |
Remove passivation layer(4) |
|
Copper or copper alloy |
Clean(1), expose metallic surface(2) |
|
Aluminium |
Clean(1), expose metallic surface(2) |
|
Steel |
Clean1, expose metallic surface(2) |
|
Zinc-plated steel |
Remove passivation, not the zinc layer(3) |
|
Hot-galvanized sheet-metal |
Clean(1), passivation need not be removed |
|
(1) Clean by means of lint-free cloth; use cleaning agent in case of serious contam-ination (see above) (2) Expose metallic
surface (3) Using a brass brush, steel brush (4) Rub slightly by hand using Scotchbrite abrasive agent (check that the Ni layer is not reduced) |
|