Downhole tool and method of use

A method of using a downhole tool, the method comprising:

• connecting the downhole tool to a workstring;
• operating a workstring to run the downhole tool into a wellbore to a desired position, the downhole tool comprising:
• a mandrel comprising:
• a body having a proximate end with a first outer diameter;
• a set of shear threads;
• a distal end with a second outer diameter;
• an angled linear transition surface;
• and an inner bore disposed between the proximate end and the distal end,
• wherein the mandrel is made from composite filament wound material,
• wherein the mandrel comprises an outer surface along the body, and an inner surface along the inner bore, wherein the set of shear threads are formed on the inner surface of the inner bore, and wherein the first outer diameter is larger than the second outer diameter;
• a composite slip disposed around the mandrel at the proximate end;
• a metal slip disposed around the mandrel at the distal end;
• a bearing plate disposed around the mandrel, the bearing plate comprising an angled inner plate surface engaged with the angled linear transition surface, and an angled outer plate surface engaged with the composite slip;
• a first cone disposed around, but not otherwise coupled to, the mandrel, the first cone also engaged with the composite slip;
• a seal element disposed around the mandrel, and between the composite slip and the metal slip;
• and
• a lower sleeve disposed around and threadingly coupled with the mandrel, and also engaged with the metal slip at the distal end;
• placing the mandrel under a tensile load;
• setting the downhole tool;
• and
• disconnecting the downhole tool from the workstring when the tensile load is of sufficient amount to cause shearing of the set of shear threads.

A method of using a downhole tool, the method comprising:

• operating a workstring to run the downhole tool into a wellbore to a desired position, the downhole tool comprising:
• a mandrel made of a composite material, the mandrel further comprising:
• a distal end;
• a proximate end;
• an outer surface;
• a flowbore extending from the proximate end to the distal end;
• and an inner set of shear threads disposed in the flowbore at the proximate end,
• wherein the mandrel comprises a first outer diameter at the distal end, a second outer diameter at the proximate end, and an angled linear transition surface therebetween, and wherein the second outer diameter is larger than the first outer diameter;
• a metal slip disposed around the mandrel proximate to the distal end;
• a composite slip disposed around the mandrel proximate to the proximate end;
• a bearing plate disposed around the mandrel, the bearing plate comprising an angled inner plate surface engaged with the angled linear transition surface, and an angled outer plate surface engaged with the composite slip;
• a first cone disposed around, but not otherwise coupled to, the mandrel, the first cone also engaged with the composite slip;
• a seal element disposed around the mandrel, and between the composite slip and the metal slip;
• and
• a lower sleeve disposed around and threadingly coupled with the mandrel, and also engaged with the metal slip at the distal end;
• placing the mandrel under a load until the downhole tool is set;
• continuing to increase the load to a point where the load is of a sufficient amount to cause shearing of the inner set of shear threads, and result in disconnection between the downhole tool from the setting tool adapter;
• dropping a ball into the wellbore in order to block the flowbore;
• and
• injecting a fluid from a surface into the wellbore, and subsequently into at least a portion of subterranean formation in proximate vicinity to where the downhole tool is set in the wellbore.