Power Section Specification
412-7850
4.125" 7:8 Lobes 5.0 Stages
Rotor Specifications
Overall Length 149.00 in
Avg. Diameter 2.286 in
Contour Length 142.00 in
Eccentricity 0.144 in
Major Diameter 2.574 in
Head Diameter 2.250 in
Head Length 7.00 in
Weight 175 lb
Thread Form 1.625-5 NOIHT
Stator Specifications
Overall Length 157.00 in
Tube OD 4.12 in
Contour Length 141.00 in
Tube ID 3.375 in
Rubber Cut-back
Side 1: 8.00 in
Side 2: 8.00 in
Weight 219 lb
Material Alloy Steel
Performance Specifications
Flow Range 95-190 GPM
Rev per Unit Volume 1.00 Rev/Gal
Speed Range 94-189 RPM
No Load Pressure Loss 102 psi
  POB PRR
Max Rec Press 1,180 psi 1,180 psi
Torque @ Max Press 3,120 ft-lbs 3,120 ft-lbs
Stall Pressure 1,780 psi 1,780 psi
Stall Torque 4,690 ft-lbs 4,690 ft-lbs
Stator Minors and Fit (in) at 70°F
  PRR POB
Group Minor Fit Minor Fit
4 2.313 -0.027 2.312 -0.026
Reline Lengths (in) Max 157 Min 151 Alternate Stator OD (in): - / -
Torque
Differential Pressure (psi) 0 1,000 Torque (ft-lb) 0
Fit Increase
Change in Temperature (°F) 0 100 200 300 Fit Increase (in) 0
Speed
Differential Pressure (psi) 0 500 1,000 1,500 Speed (RPM) 0
Mechanical Power
Differential Pressure (psi) 0 1,000 Mechanical Power (hp) 0
Torque
Differential Pressure (psi) 0 200 400 600 800 1,000 1,200 1,400 Torque (ft-lb) 0 1,000 2,000 3,000
Fit Increase
Change in Temperature (°F) 0 50 100 150 200 250 300 350 Fit Increase (in) 0 0.02 0.04 0.06 0.08
Speed
95 GPM 143 GPM 190 GPM Differential Pressure (psi) 0 200 400 600 800 1,000 1,200 1,400 Speed (RPM) 0 50 100 150 200 250
Mechanical Power
95 GPM 143 GPM 190 GPM Differential Pressure (psi) 0 500 1,000 1,500 Mechanical Power (hp) 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.