SURFACE BUMPER JARS
THE LOGAN SURFACE BUMPER JAR IS USED WHENEVER THE DOWNOLE DRILLING, FISHING, OR WASHOVER RUNNING STRING BECOMES STUCK AND REQUIRES A HEAVY DOWNWARD FORCE TO RELEASE IT.
It is often used to free key seated drill pipe and drill collars, and initiate sharp jarring blows down the string to actuate drilling bumper subs, bumper safety joints, and other similar downhole bumping tools. It is also useful for transmitting heavy downward impact to release embedded grappling tools. Since it is not necessary that the two striking surfaces meet, the tool’s 48-inch stroke allows the fish to be hammered down farther than what is possible with conventional jarring tools. Because it is intermittently used only on the surface to release a stuck fish, this tool has an extended service life when compared to conventional bumper subs.