ERT™ Power Section Specification (Metric)
725ERT7872
184.2 mm 7:8 Lobes 7.2 Stages
Rotor Specifications
Overall Length 6400.8 mm
Avg. Diameter 114.02 mm
Contour Length 6096.0 mm
Eccentricity 6.79 mm
Major Diameter 127.61 mm
Head Diameter 120.65 mm
Head Length 304.8 mm
Weight 659 kg
Thread Form 3.688 XDV
Stator Specifications
Overall Length 6604.0 mm
Tube OD 184.15 mm
Contour Length 6032.5 mm
Tube ID 129.39 mm
Rubber Cut-back
Side 1: 228.6 mm
Side 2: 342.9 mm
Weight 528 kg
Material Alloy Steel
Performance Specifications
Flow Range 1893-3028 LPM
Rev per Unit Volume 0.07 Rev/L
Speed Range 125-200 RPM
No Load Pressure Loss 1572 kPa
  POB XTH
Max Rec Press 13,730 kPa 14,710 kPa
Torque @ Max Press 28,310 N-m 30,330 N-m
Stall Pressure 25,120 kPa 26,910 kPa
Stall Torque 51,800 N-m 55,500 N-m
Stator Minors and Fit (mm) at 21°C
  XTH POB
Group Minor Fit Minor Fit
2 114.15 -0.13 114.15 -0.13
 
Reline Lengths (mm) Max 6604 Min 6452
Alt. Stator OD (mm)   -   -
Alt. Rotor Diameter (mm) - - - -

Max DP for reliable operation will vary based on
operational conditions. Refer to ERT Operational
Guidelines for guidance.

Torque
Differential Pressure (kPa) 0 10,000 20,000 Torque (Nm) 0
Fit Increase
Change in Temperature (°C) 0 50 100 150 Fit Increase (mm) 0
Speed
Differential Pressure (kPa) 0 10,000 20,000 Speed (RPM) 0
Mechanical Power
Differential Pressure (kPa) 0 10,000 20,000 Mechanical Power (Kw) 0
Torque
Differential Pressure (kPa) 0 5,000 10,000 15,000 20,000 Torque (Nm) 0 10,000 20,000 30,000 40,000
Fit Increase
Change in Temperature (°C) 0 20 40 60 80 100 120 140 160 180 Fit Increase (mm) 0 0.2 0.4 0.6 0.8 1
Speed
1893 LPM 2461 LPM 3028 LPM Differential Pressure (kPa) 0 5,000 10,000 15,000 20,000 Speed (RPM) 0 100 200 300
Mechanical Power
1893 LPM 2461 LPM 3028 LPM Differential Pressure (kPa) 0 5,000 10,000 15,000 20,000 Mechanical Power (Kw) 0 200 400 600
©2026 NOV. All rights reserved. Except as noted, all trademarks referenced in this document are trademarks of NOV. Performance curves describe theoretical performance with 175°F (79°C) water and are for reference only. Operational fit and drilling conditions will affect performance. Operation above maximum recommended limits will reduce life. Specification data are subject to change without notice.
PS App v.