The safety clamps are used to griping firmly around the drill collar or other non-shouldered tools at the upper part, to form a flange ring for preventing the drill collar or other tools slide off through the opening of the slips, and fall down to the well bore, during tripping operations. But the Clamp must be taken off soon after the connection of the drill collar and upper string is completed. Never lower the clamp into the wellbore with the string. For different size of drill collar or other tools, it needs only to alter the number of grip chain links, to fit the tool size.
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