Power Section Specification
475-7838
4.75" 7:8 Lobes 3.8 Stages
Rotor Specifications
Overall Length 178.00 in
Avg. Diameter 2.607 in
Contour Length 172.00 in
Eccentricity 0.164 in
Major Diameter 2.936 in
Head Diameter 2.750 in
Head Length 6.00 in
Weight 276 lb
Thread Form 2 3/8" HEF
Stator Specifications
Overall Length 187.00 in
Tube OD 4.75 in
Contour Length 171.00 in
Tube ID 3.750 in
Rubber Cut-back
Side 1: 8.00 in
Side 2: 8.00 in
Weight 385 lb
Material Alloy Steel
Performance Specifications
Flow Range 100-325 GPM
Rev per Unit Volume 0.51 Rev/Gal
Speed Range 50-164 RPM
No Load Pressure Loss 157 psi
  POB XTH PRR
Max Rec Press 900 psi 990 psi 900 psi
Torque @ Max Press 4,680 ft-lbs 5,140 ft-lbs 4,680 ft-lbs
Stall Pressure 1,350 psi 1,490 psi 1,350 psi
Stall Torque 7,010 ft-lbs 7,710 ft-lbs 7,010 ft-lbs
Stator Minors and Fit (in) at 70°F
  PRR POB XTH
Group Minor Fit Minor Fit Minor Fit
0 2.612 -0.005 2.610 -0.003
4 2.638 -0.031 2.635 -0.028 2.631 -0.024
5 2.641 -0.034 2.638 -0.031
7 2.647 -0.040 2.650 -0.043
Reline Lengths (in) Max 187 Min 181 Alternate Stator OD (in): 5.000 / -
Torque
Differential Pressure (psi) 0 500 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 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 Torque (ft-lb) 0 2,000 4,000 6,000
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
100 GPM 213 GPM 325 GPM Differential Pressure (psi) 0 200 400 600 800 1,000 1,200 Speed (RPM) 0 50 100 150 200
Mechanical Power
100 GPM 213 GPM 325 GPM Differential Pressure (psi) 0 200 400 600 800 1,000 1,200 1,400 1,600 Mechanical Power (hp) 0 50 100 150
©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.