The two piece seal features two channels, one stationary and one that rotates with the motor shaft. In between the channels is a greased cavity to reduce friction. In comparison with the current industry commonplace slinger seal guard, the Excessive Duty Seal Guard adds three barriers to protect motors from contamination.

Developed in the 1940s, the technique of hydraulic motors pdf fracturing has change into increasingly vital in oil drilling. It comes in helpful with «tight» reservoirs — the place the rocks containing the oil don’t have giant pores. Which means the oil stream from the rocks is weak, and drilling a easy nicely into the rock won’t get much of the oil out.

­In this article, we’ll look at probably the most famous fighters, the F-15. This exceptional aircraft is getting up in years — it has been around since the early ’70s — but it’s still an important piece of the U.S. arsenal. In accordance with the U.S. Air Pressure, it has an ideal fight file, with over one hundred victories and zero defeats. As we’ll see, its success is due to its phenomenal maneuverability, advanced digital gear and fearsome firepower.