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The Hosmer Button

The great, Greta blowout in Refugio County, Texas; 1937. The crater is boiling and the failed relief well can be seen in the background. The road is actually State Highway 77, looking north, toward Victoria.

In the first three decades of the 1900's new oil and gas discoveries were being made throughout the United States and new wells often found Mama Earth to have way more bottom hole pressure than folks could handle. Allowing wells to come in and blow over the crown were pretty cool to watch for awhile, but that shit got real old, real fast. If we all had 1/1000th of the oil that got wasted in earthen pits, are burned up in well fires, just showing off, we'd all have more money than that fella, Ben Gump, whoever the hell he was.

To stem the madness, mud weights started going up, folks started setting multiple strings of casing above known over-pressured zones and big, full open valves were placed on those surface strings that would allow cable tools to pass thru, etc., then could be closed when those tools got blown out of the hole, or torpedoes were dropped for stimulation and the well allowed to come in.

By the early 1920's folks were using rotary tables consistently and with them came several new ideas about blowout preventers, including the first "ram" type preventers that would close around drill pipe, invented in 1922 by two Texas names named Abercrombie and Cameron, the later the founder of Cameron Iron Works. These early ram BOP's had to be closed manually, usually big wheels. In the early 1940's a fella named Granville Knox invented the first annular type, hydraulically closed preventer system that eventually became known as Hydril.

Another lesser-known blowout preventer back in the day was the Hosmer "Button." This "prevention" system was designed in California and involved a preventer body, or seat, bolted or welded to surface casing, and a wrap around, pack-off element, called a "button" that could be clamped to the drill pipe, then lowered into the seat, rotated and latched down. The latch-down sealed the pack off in the preventer body and weight caused the packing element to swell. This all presumably kept things under reasonable control so mud could be pumped below the pack-off to kill the well.

Typical Hosmer well head assembly

Diagram of the pack-off element, or button in the Hosmer system and how it was seated in the BOP


Clearly this was not an effective prevention device for high-pressured, or even normal pressured areas. If the well kicked, or was swabbed in, installing the pack off button on the drill pipe, below a tool joint, with shit blowing in all the hand's faces was obviously problematic. Then the driller had to lower the packing element into the bowl, make sure it was centered, the hands pushing and pulling on the drill string to get the button down in the bowl, with more shit being blown everywhere, and finally the drill string had to be rotated to achieve latch-down and sealing off the flow.

I am quite certain this procedure hair-lipped a many a hand over the years, or worse, took their heads plum off.

Patent Application

Hosmer BOP advertisement showing both the (tapered) button and the button seated in the surface casing body, left.

In 1947 numerous attempts were made to clamp a Hosmer button onto drill pipe in a big, blowing well in the province of Alberta, Canada. Those attempts failed, surface control was lost completely, and the results were one of the nastiest blowouts in Canadian history, a well that blew for months thru what was called a "40 acre choke." We'll be writing about that blowout soon on Oily Stuff; stay tuned. It was a doozy.

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