Typical gov’t exercise of “measure it with a micrometer, mark it with a grease pencil, cut it with a hatchet”.
All that documentation and detail, …time, money, man-power and resources …running a technical experiment…. which results in completely USELESS data…because they FAILED to even specify the lubricant used.
No grease pencil or hatchet used here. The experiment was devised to investigate possible causes of previous failure of a field assembly. Its focus was to demonstrate the effects the lubricant had on the mechanical structure and integrity of the assembly and the inaccuracies of the engineering formulas that were used in that assembly . The experiment was not intended to quantify the effects of the lubricant for suture use in the field so the specific lubricant used in the experiment is not important. They are focused on providing guidance for developing engineering and assembly practices to be used in the future. The summary which highlights their concerns about previous and future practices:
Several conclusions are noted:
Although slight wear, burnishing, and galling were observed on the clamped flange in the region contacted by the bolt bead, the nut threads showed little evidence of wear and remained a class 3B fit throughout the test.
Tensions considerably in excess of the values predicted wlth the commonly used formula, T = K x D x F with K = 0.1, were obtained with a bolt which was carefully lubricated on the threads and the head. In the teats at the service assembly torque of 606 N,-m (447 lb-ft) the ratio of achieved bolt tension to predicted tension was 1,67
A marked decrease in bolt tension to 39% of the initial value as observed during 50 torque applications without relubricatlon, a tension approximately 20% greater than the predicted value for dry assembly, K - 0.2, was obtain for a degreased, dry boLt.
Consistent tension having a variation of only *1% was obtained when lubrlcatlon was applied to the bolt head prior to each torquing
Well I just had my pump replaced two weeks ago and if it unscrews itself the callback will be on their dime. Its 2 HP pump on 30 sections of 1" x 20' schedule 120 PVC pipe - no safety rope.
The new pump was doped and screwed to the well pipe then it and the 6/3 pump cable was secured with a long heavy wrap of 2" PVC pipe tape. Each successive pipe joint was doped and then the 6/3 well cable was taped to the joint with another long heavy wrap of pipe tape. The cable was also taped to the midpoint of each section of pipe. I am pretty sure its not going to unscrew itself.