ERT™ Power Section Specification (Metric)
500ERTcr7826
127 mm 7:8 Lobes 2.6 Stages
Rotor Specifications
Overall Length 5588.0 mm
Avg. Diameter 69.77 mm
Contour Length 5435.6 mm
Eccentricity 4.42 mm
Major Diameter 78.61 mm
Head Diameter 69.85 mm
Head Length 152.4 mm
Weight 147 kg
Thread Form 2 3/8" HEF
Stator Specifications
Overall Length 5822.9 mm
Tube OD 127.00 mm
Contour Length 5410.2 mm
Tube ID 85.47 mm
Rubber Cut-back
Side 1: 206.4 mm
Side 2: 206.4 mm
Weight 272 kg
Material Alloy Steel
Performance Specifications
Flow Range 568-1136 LPM
Rev per Unit Volume 0.07 Rev/L
Speed Range 40-80 RPM
No Load Pressure Loss 1289 kPa
  POB XTH
Max Rec Press 4,960 kPa 5,310 kPa
Torque @ Max Press 9,680 N-m 10,370 N-m
Stall Pressure 9,070 kPa 9,720 kPa
Stall Torque 17,720 N-m 18,980 N-m
Stator Minors and Fit (mm) at 21°C
  XTH POB
Group Minor Fit Minor Fit
0 69.49 0.28 69.60 0.18
3 70.00 -0.23 70.10 -0.33
 
Reline Lengths (mm) Max 5823 Min 5671
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 5,000 Torque (Nm) 0
Fit Increase
Change in Temperature (°C) 0 50 100 150 Fit Increase (mm) 0
Speed
Differential Pressure (kPa) 0 5,000 Speed (RPM) 0
Mechanical Power
Differential Pressure (kPa) 0 5,000 Mechanical Power (Kw) 0
Torque
Differential Pressure (kPa) 0 2,000 4,000 6,000 8,000 Torque (Nm) 0 5,000 10,000 15,000
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
568 LPM 852 LPM 1136 LPM Differential Pressure (kPa) 0 1,000 2,000 3,000 4,000 5,000 6,000 7,000 8,000 Speed (RPM) 0 50 100
Mechanical Power
568 LPM 852 LPM 1136 LPM Differential Pressure (kPa) 0 2,000 4,000 6,000 8,000 Mechanical Power (Kw) 0 50 100
©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.