Wireline Tensile Strength Ductility Tester

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					Wireline Tensile Strength &
      Ductility Tester
     Why is The Ductility Wireline
•  We all know that strength of individual strands
   are important, we calculate our Cable Head
   strength from that number. But when we pull on
   that Cable Head or we pump against that head
   how do we know what the condition of the head
   is then. We have all seen Cable Heads that were
   reheaded to a certain weight and when worked
   for a short time, come apart at a considerably
   lesser amount. Also we have reheaded other
   lines, gotten stuck, and worked the line for an
   equal length of time and pulled out at what we
   built the head for. Why? ( next page)
•  In most cases it is because of fatigue of the wire.
   Many of you that own or have used a Cable
   Head Testing Machine have noticed that when
   using the Strand Tester on the machine a new .
   040 wire strand (sweet line) will lose about 8% of
   its strength when bent over a cone radius. Older
   wire can exceed 20% when bent over that same
   radius. This decline is an indirect function of the
   lines ductility if the strand remains the same
   diameter. What is needed is a machine that
   delivers data that is a direct function of ductility.
 Description of the Wireline Tensile
   Strength and Ductility Tester
•  The previous page show a “T S & D” Tester. It
   measures 15” long and 2” in diameter. It tests
   12” of line between its two wire clamps. On each
   end are the wire clamps. From left to right the
   first device is the Rotating Wire Clamp. Next is
   the Tension Sleeve. Next is the Threaded Union.
   It is attached to the Pressure Cylinder. On the
   inside of the Pressure Cylinder is a piston and
   mandrel. ( the mandrel is bored to allow wire to
   be placed through it) On the end of the Mandrel
   is the Non Rotating Wire Clamp. (next page)
•  Above the main body of the Tester, from
   left to right, is The Pressure Transmitter.
   (This Transmitter is Optional.) Next is the
   Gauge. The gauge can be 0-600 PSI/lbs
   as shown or it can be larger or smaller. As
   shown, this machine is rated to 1500 PSI/
   lbs because of the wire clamps. When
   pulling wire that exceeds 750 lbs an
   auxiliary hydraulic cylinder pump can be
   added as shown on the 4th photo.
•  The previous photo shows a couple of tools that come
   with the T S & D Tester. The device is best secured in a
   pipe vise but will work fine in a jaw vise. A strand of
   wireline is inserted through the Rotating Wire Clamp,
   through the mandrel bore and clamped in the Non
   Rotating Wire Clamp. To test the tensile strength of the
   wire the lever handle (shown on the left side of the
   photo) is attached to the Rotating Wire Clamp. The Dow
   Pin Socket Wrench is inserted into one of the multiple
   bores in the Tension Sleeve. While holding the Rotating
   Wire Clamp in place the Tension Sleeve is Rotated
   causing the wire to tighten and pressure to build until the
   wire fails. Note the pressure and insert (next page)
•  another length of the same line and clamp in like
   manner. Rotate the Tension Sleeve until the pressure /
   lbs is within 80% of the breaking point of the previous
   wire piece. Next, Rotate the Rotating Wire Clamp slowly
   while counting the revolutions until the wire breaks or it
   reaches 20 turns. If the wire reaches 20 turns rotate the
   Tension Sleeve until the wire parts. An improved plow
   steel wire that reaches 20 turns and has to be broken by
   hydraulic force is considered in excellent shape and will
   fatigue very slowly. An example of excellent line and
   poor line is shown in graph form in the graphs at the end
   of this presentation. The “poor line passed the bend test
   and made 10 wraps around it’s own diameter before
   breaking. The difference between this line’s straight line
   breaking strength and bent over a cone radius was 20%.