[[TitleIndustry]]

ISO 8434-1 Overtightening test standard

Date:Jun 15, 2019

ISO 8434-1 Overtightening test standard including  Connectors with cutting rings and

Connectors with O‑ring seal cone (DKO) as follow:


For each size of Connectors with cutting rings, three samples each of the cutting ring connection ends shall be tested.

Tighten the cutting ring connection end to finger-tight position plus the number of turns recommended by the manufacturer, and record the resulting torque. Apply an overload of 30 % of the recorded torque, not to exceed 100 Nm. The connection shall be capable of withstanding this overload with no indication of the following failures:

The nut cannot be removed and swivels freely after breakaway;

Visible cracks or severe deformation appear that would render the connector component unusable.


For each size of Connectors with O‑ring seal cone (DKO), three samples of the O-ring seal cone (DKO) ends shall be tested.

Apply the manufacturer’s recommended torque plus an overload of 30 % of the recommended torque, not to exceed 100 Nm. The connection shall be capable of withstanding this overload with no indication of the following failures:

The nut cannot be removed and swivels freely after breakaway;

Visible cracks or severe deformation appear that would render the connector component unusable.



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