Test Conditions:
Chain Tested: NM720-CS, 6" Pitch 22 links, 11 'total
Pin Material: Glass Reinforced Nylon
Sprocket Material: Ultra High Molecular Weight PE
Sprocket Size: 23HT, 22.21" P.D.
Applied Load: 800 lbs (via Air Cylinder)
Chain/Sprocket Articulations: 61,000 articulations
Drive Shaft Speed: 28.75 rpm
   
Testing Procedure:
  • Chain is to be attached over two sprockets under self weight load. Load is slowly brought up to 800 lbs under static conditions. Tank is started under full, constant load regulated by attached pressure gauge/regulator.
    • Chain to be partially submerged, (approx. 45%) in room temperature water, per setup diagram.
    Setup
     
Test Results:
  PIN#1 PIN#2 PIN#3 INSIDE BARREL
#1 		INSIDE BARREL
#2		 INSIDE BARREL
#3
Initial
Readings ["]		 0.862 .863 .860 0.885 0.887 0.887
Final Readings ["] 0.855 .854 .856 0.897 0.894 0.893
Total Calculated
Wear ["]		 0.007 0.009 0.004 0.008 0.007 .005
Total Wear/Yr. ["/yr] 0.0007 0.0009 0.0004 0.0008 0.0007

0.0005
Chart 1. Inside Chain/Pin Wear
 
  Outside
Barrel #1		 Outside
Barrel #2		 Outside
Barrel #3		 Chain/
Sprocket
Clearance #1		 Chain/
Sprocket
Clearance #2		 Chain/
Sprocket
Clearance #3
Initial Readings
["] 		1.509 1.506 1.507 0.12 0.13 0.13
Final Readings
["] 		1.499 1.491 1.498 0.25 0.26 0.25
Total Calculated
Wear ["]		 0.010 0.015 0.009 0.13 0.13 0.13

Total Wear/Yr.
["/yr.]

0.001 0.0015 0.0009 0.013 0.013 0.013
Chart 2. Outside Chain/Sprocket Wear
 
Analysis
     
  Pin Wear
  • Maximum Pin Wear was 0.009" under a simulated 10 year period.
  • Examination of pin shows uniform wear across only 90° portion of pin.
   
    Inside Barrel Wear
  • Maximum Inside Barrel Wear was 0.008" under a simulated 10 year period.
  • T-Head feature of pin fits tightly trough barrel.
   
    Outside Barrel Wear/Sprocket Wear
  • Maximum Ourside Barrel Wear was 0.015" under a simulated 10 year period.
  • Maximum Sprocket/Chain Clearance Wear was 0.13" over a simulated 10 period.
  • The results indicated that majority of wear occurred on the sprocket teeth, likely due to the difference in hardness of the two materials.