ERT™ Power Section Specification (Metric)
650ERT7867
165.1 mm 7:8 Lobes 6.7 Stages
Rotor Specifications
Overall Length 6381.7 mm
Avg. Diameter 101.94 mm
Contour Length 6159.5 mm
Eccentricity 6.39 mm
Major Diameter 114.73 mm
Head Diameter 101.60 mm
Head Length 222.2 mm
Weight 406 kg
Thread Form 3.000 XDV
Stator Specifications
Overall Length 6604.0 mm
Tube OD 165.10 mm
Contour Length 6108.7 mm
Tube ID 140.72 mm
Rubber Cut-back
Side 1: 247.6 mm
Side 2: 247.6 mm
Weight 436 kg
Material Alloy Steel
Performance Specifications
Flow Range 1136-2650 LPM
Rev per Unit Volume 0.07 Rev/L
Speed Range 81-189 RPM
No Load Pressure Loss 1524 kPa
  POB XTH
Max Rec Press 12,770 kPa 13,680 kPa
Torque @ Max Press 24,380 N-m 26,120 N-m
Stall Pressure 23,370 kPa 25,040 kPa
Stall Torque 44,620 N-m 47,810 N-m
Stator Minors and Fit (mm) at 21°C
  XTH POB
Group Minor Fit Minor Fit
B 101.63 0.32
0 101.88 0.06 101.93 0.01
1 102.21 -0.27
 
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
Speed
1136 LPM 1893 LPM 2650 LPM Differential Pressure (kPa) 0 5,000 10,000 15,000 20,000 Speed (RPM) 0 50 100 150 200 250
Mechanical Power
1136 LPM 1893 LPM 2650 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.