ERT™ Power Section Specification
1125ERTcr7848
11.25" 7:8 Lobes 4.8 Stages
Rotor Specifications
Overall Length 235.50 in
Avg. Diameter 5.662 in
Contour Length 226.50 in
Eccentricity 0.353 in
Major Diameter 6.367 in
Head Diameter 5.500 in
Head Length 9.00 in
Weight 1487 lb
Thread Form 2 7/8" API Reg
Stator Specifications
Overall Length 247.00 in
Tube OD 11.25 in
Contour Length 222.00 in
Tube ID 6.541 in
Rubber Cut-back
Side 1: 12.50 in
Side 2: 12.50 in
Weight 3964 lb
Material Alloy Steel
Performance Specifications
Flow Range 600-1200 GPM
Rev per Unit Volume 0.11 Rev/Gal
Speed Range 63-127 RPM
No Load Pressure Loss 228 psi
  POB XTH
Max Rec Press 1,330 psi 1,420 psi
Torque @ Max Press 32,980 ft-lbs 35,330 ft-lbs
Stall Pressure 2,430 psi 2,600 psi
Stall Torque 60,340 ft-lbs 64,660 ft-lbs
Stator Minors and Fit (in) at 70°F
  XTH POB
Group Minor Fit Minor Fit
0 5.652 0.010 5.652 0.010
1 5.660 0.002 5.660 0.002
4 5.682 -0.021 5.682 -0.021
7 5.700 -0.038 5.700 -0.038
 
Reline Lengths (in) Max 247 Min 241
Alt. Stator OD (in)   9.625   -
Alt. Rotor Diameter (in) - 5.632 - -

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

Torque
Differential Pressure (psi) 0 1,000 2,000 Torque (ft-lb) 0
Fit Increase
Change in Temperature (°F) 0 100 200 300 Fit Increase (in) 0
Speed
Differential Pressure (psi) 0 1,000 2,000 Speed (RPM) 0
Mechanical Power
Differential Pressure (psi) 0 1,000 2,000 Mechanical Power (hp) 0
Torque
Differential Pressure (psi) 0 500 1,000 1,500 2,000 Torque (ft-lb) 0 10,000 20,000 30,000 40,000 50,000
Fit Increase
Change in Temperature (°F) 0 50 100 150 200 250 300 Fit Increase (in) 0 0.02 0.04 0.06
Speed
600 GPM 900 GPM 1200 GPM Differential Pressure (psi) 0 500 1,000 1,500 2,000 Speed (RPM) 0 50 100 150
Mechanical Power
600 GPM 900 GPM 1200 GPM Differential Pressure (psi) 0 500 1,000 1,500 2,000 Mechanical Power (hp) 0 200 400 600 800 1,000
©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.