In the early 1930s, the demand for oil was rising, but oil prices were low. Costs for new exploration and production were very high, and oil companies needed a way to find more oil with a minimal expenditure of money.

Across America were numerous cased wells which produced poorly or not at all. Various methods had been tried to get at the oil-bearing formations in these wells — with little success.

A new and effective method of casing perforation was needed, one that could accurately reach the profitable strata without splitting the casing or breaking the cement-to-casing bonds.

Any method which met this challenge had to provide extreme accuracy and flexibility in the placement of the holes. High penetration power was also imperative; the device had to go through at least two cemented casing strings and then into the formation.

Two guys who had an idea
In 1930, two enterprising oil-field tool salesmen, Bill Lane and Walt Wells, came up with the idea of using guns to get the oil. They envisioned a tool which would shoot steel bullets through casing and into the formation.

The idea sounded so simple that Lane and Wells felt certain someone must have received a

The first successful perforating gun test in 1932 took place at in a well filled with heavy drilling mud. (All photos courtesy of Baker Atlas)
patent on it already. A quick patent search by the duo proved they were right.
In 1929 Sidney Mims, an experienced oil man, had been granted a US Patent #1582184 “Method and Means for Perforating Well Casings.” The only problem was that his design did not work.

Lane and Wells traced Mims’ address to an Elks Club in Los Angeles. The two salesmen waited until midnight when Mims finally came in.

During their discussions, Mims admitted his design failed, but he was willing to sell the patent to Lane and Wells. In a short time they bought the patent, formed the Lane-Wells company in Los Angeles, Calif., and started to develop their own bullet perforator.

Bullet perforating 101
The operation of a bullet perforator was straightforward:
• Lower a cylinder containing several single-shot guns into a cased hole. Stop the device at a depth where you suspect there could be an oil-producing layer, and then fire the guns.
• Bullets passed through the casing and into the formation, producing small channels and shattered rock. Oil would then pass from the formation into the casing string.

Gun assembly challenges
Producing a reliable working gun, however, proved difficult at first. A thorough study of the Mims patent by Lane and Wells revealed several challenges.

To operate in a high-pressure well environment, each gun had to be sealed to keep the powder charge dry. A special powder mixture unaffected by the high well temperatures was also required.

The cable suspending the perforator into the well was problematic. It required special insulation to withstand the severe well conditions. Without this, the electrical firing impulse would not travel to the perforator. No company in America made such a cable.

Perforation guns had to fire one-at-a-time, in sequence. Damage to the casing would result if
In December 1932 a multi-shot perforating gun added 150,000 bbl of production from a well set for abandonment.
all guns fired simultaneously. Such firing requirements necessitated a special controller, attached to the device and operated from the surface by electric impulses traveling through the cable. A controller like this had never been designed or manufactured.

The entire perforation system demanded an extremely high degree of safety. Accidental gun firings were out of the question. Traditional methods of percussion caps to detonate the guns were scrapped. Each gun had to fire by operator-controlled electrical detonation.
One operator and a rig hand at the well surface controlled the entire sequence of activities — from lowering the tool in the well to detecting the perforation zone to firing the guns to retracting the tool. New, sophisticated and reliable controls were needed.

Determining which alloy steels would provide sufficient tensile strength to withstand the pressures built up by the powder detonation was a concern. The size and shape of the bullets had to be designed, too.

Risky test
By early 1932, practical solutions to all of these problems were found. A test was then performed with the cooperation of a major oil company which had been closely following the tool’s development.

A short section of 6 5/8-in., 26-lb casing was cemented within a piece of 8 5/8-in., 36-lb pipe.

A two-shot bullet perforator was placed within the test section, and the entire assembly was lowered to a depth of 1,600 ft (488 m) in a well full of heavy rotary mud.

The shots were fired and, upon raising the units to the surface, inspection revealed that both bullets penetrated the test section, leaving clean holes with no splitting of the casing.

The oil company was so favorably impressed by the penetration and the successful operation under hydrostatic pressure of 1,000 psi that it turned over to Lane-Wells one of its abandoned wells and offered the services of a crew whenever desired.

Skepticism abounds
Most oil companies, though, were initially skeptical about the idea of shooting holes in casing. No oil company wanted to take a chance on using the device in a producing well.

It was not until December 1932 that Union Oil Co. allowed Lane-Wells to test the bullet perforator in a well which was ready for abandonment.

On a brisk winter day in California, Bill Lane lowered the device into the La Merced No. 14 well. Eighty-seven shots were fired in 11 runs in the well. This perforation activity brought the well back from producing nothing to 40 b/d of oil. In the following years, the well brought in more than 150,000 additional barrels of oil.

Lane-Wells is now in business
A short time after this test, Lane-Wells announced to the oil industry that they could supply a multiple-shot perforator which fired bullets individually by electrical detonation of the powder charges — and the entire device would be controlled from the well surface by two men.

As news of this successful test spread across the oil fields, many operators wanted the service. For several years, Lane-Wells could not keep up with the demand for its services.

New tools of the trade
Lane-Wells engineers designed and built special trucks to provide the perforation service. A large, dedicated assembly shop on the company site built these vehicles from the chassis up as fast as possible.

Each truck was equipped with a built-in hoist, 8,000 to 12,000 ft (2,440 to 3,660 m) of the
By 1935, the Lane-Wells perforating trucks had all the business they could handle.
special conductor-core cable, a line spooler, generators for current supply, special racks for the guns and other necessary equipment.

The control compartment of the truck was designed with all controls grouped at a control panel so that the gun operator — “The Shooter” — could see a display of the gun location and the line weight at all times.

To ensure the high degree of accuracy in placing the shots, the Lane-Wells engineers developed a sheave assembly with an electrically operated depth-measuring device.
The sheave also contained a newly designed and electrically operated weight indicator which provided a visual registration of “tool pickup” and enabled the checking of fluid levels.

By late 1935 Lane-Wells had a small fleet of trucks, and the company was growing rapidly into being the leading provider of well-perforation technology.

Several years later, Lane-Wells became part of Baker Atlas.

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