Date: January 2017
Country / Region: Central Sweden
Industry: Water & Energy
Application: Water Wells, GSHP Applications
Client Name: Olsen Entreprenad AB
Family company built in 2004 by the Olsen brothers, that works in the central zone of Sweden, from Dalarna to Södertälje. They have 2 rigs and 2 compressors, and they drill around 600 holes per year in both Water well and GSHP applications.
Overview and General Results (conclusion):
Client was drilling water wells at a target depth of 220 mts, where the bit started to get stuck at 200 mts, so a decision was made to test the Puma PM4.3 TD40 Hammer. A study was held on three different holes to analyze the ROP of the different hammers used, as well as the bit’s gauge dimension. The Puma M4.3 TD40 Hammer showed an average ROP of 63,6 m/h, a +2.9% increase at equal conditions.
- First hole: Drilled with PM4.3 TD40 hammer and Puma TD40 115 mm bit. The first 9 m where cased using a competitor´s hammer. The initial goal was to reach 220m. The drilling kept going without interruptions, but at 200m (198-201m) the bit started to get stuck, so in order to prevent losing the whole drill string drilling stopped. Back on surface, the bit showed that one insert fell off and 4 others were broken, meaning the insert that fell off probably damaged the others. There were marks on the hammer that showed clearly that it was that insert that was getting stuck and not allowing the hammer to turn normally. The rotation used was around 110 RPM (recommended rotation is around 60-85).
- Second hole: Drilled with a competitor`s hammer and bit. The hole was drilled to 240m to recover 20 meters lost from the first hole, using the same rotation as the first hole drilled. No problems where identified and the bit showed normal wear.
- Third hole: Drilled with PM4.3 TD40 hammer and Puma TD40 115mm bit. As the others, first 9m where cased using a competitor´s hammer. Drilling with the PM4.3 TD40, rotation was reduced to the recommended 85 RPM. Drilling took two days, pressure for the first day was fixed to 30 bar, and the second day it was turned up to 35 bar. There weren’t any problems drilling this hole, and when the bit was brought up it hadn’t any broken or fallen out inserts.
- The average ROP for competitor’s hammer at 35 bar was 62,4 m/h with a standard deviation of 5,2 m/h.
- The average speed for the Puma M4.3 TD40 hammer at 35 bar was 61,8 m/h with a standard deviation of 5,6 m/h.
- The third hole was made at less rotation. If only equal conditions are considered the Puma M4.3 TD40 hammer have an average ROP of 63,6 m/h and a standard deviation of 6 m/h.
- In the first hole, after 200m drilling, the Puma TD40 bit gauge dimension is 113,0 mm.
- In the second hole, after 240m drilling, the competitor’s bit gauge dimension is 113,7 mm.
- In the third hole, after 210m drilling, the Puma TD40 bit gauge dimension is 112,98 mm.
- The bits were not measured before they got into the hole, and there seem to be differences.
The following chart shows the ROP (Rate of penetration) depending on depth:
In the next chart, the ROP data is in order from min to max, to facilitate comparison, and only data got at 35bar is considered:
In the following chart, a time comparison is made, only considering the effective drilling time, and not considering the time of adding pipes to the string: