Crude work: Oil methods fascinating. (original) (raw)

This past winter I had the privilege of restoring a working model of a wooden oil field derrick using the old cable tool method of drilling for oil. During the project for the White Deer Land Museum in Pampa, I was forced to research and learn why and how each component part worked in order to restore the equipment to working condition. By the time I finished, I became fascinated with the simplicity of this crude equipment and how man had created and operated it under trying times and in extremely remote locations.

First of all, most wooden derricks were built and used during the "horse-power era" when teams pulling wagons were the only conveyances available. Loads were strictly limited in size and weight. This meant that anything heavy or bulky had to be broken down into lesser weights that horses and mules could haul. Labor was plentiful and cheap so most drilling equipment was built on location using only critical manufactured parts ordered from catalogs. Further economy was utilized if the well was a producer using the same original drilling equipment to pump and produce the oil.

Most people think an oil derrick is built like a windmill tower with bracing nailed to long leg timbers. Not so, as derricks are much taller, the bases wider and the tower must withstand much heavier weights than windmill towers. The process of construction is much more critical.

To withstand this use, derricks do not use corner timbers, but instead use L-shaped cornices for legs. All bracing including "bands," and X bracing is fitted and butted together inside the cornice. Nails are used only to hold the bracing in place. The strength comes from the jointing and butting. Also remember, during the time of wooden oil derricks, concrete use was limited. The entire derrick and equipment were mounted on heavy timbered "mud sills" laid on the ground and covered with a wooden plank floor. The derricks were free-standing and built on location. Most wooden derricks were powered by steam engines as the internal combustion engine had not been produced yet. This required a steam boiler, water tank and boiler fuel of some source. This was also before geared, reversible transmissions, clutches and V-belts, so flat belts and ropes were used to provide power to the winches and band wheel. Interestingly, all equipment ran the same direction and reversing could be accomplished only by twisting belts or ropes. Later, reversing winches speeded up the drilling process.

Since all equipment operated at slow revolutions, many bearings were wooden requiring frequent lubrication. Braking of the winches was accomplished by heavy metal bands clamped around the wooden flywheels of the equipment.

The actual digging of the hole was judged by feeling the jar on the cable as it raised and dropped the bit against the formation in the bottom of the hole. For this reason, the cable tool drilling crews were called "Jarheads."

Today's rotary drilling crews would laugh at the old-time crude equipment but somehow it got the job done. The crews were a tough, hardy lot who continually improved their equipment as they gained experience in the always-changing oil formations. We salute the old "Jarhead Crews" of the wooden derrick and cable tool drilling days.

� Delbert Trew

"It's All Trew" February 28, 2008 Column
E-mail: trewblue@centramedia.net.