However, 4 of the 52 wells in the specific township and range had blown out in the past five years.

All wells in the area appeared to be normal pressured until 9,800 ft.

The rig was destroyed and natural resources were lost until the well was killed three weeks later.Ī study was conducted that yielded the following results: An underground blowout occurred that soon erupted into a surface blowout. At that point, responsibility would be turned over to the oil company.ĭrilling was uneventful until a depth of 8,750 ft was reached. casing to 1,800 ft and use a 9.5-lbm/gal mud to 9,000 ft in a 9⅞-in. Because the prospect well was to be drilled to 9,000 ft, pressure problems were not anticipated. Although the records were approximately 15 years old, it appeared that the formation pressures would be normal to a depth of 9,800 ft. The drilling superintendent called a bit company and obtained records on two wells in the section where the prospect well was to be drilled. The contractor was reputable and had a successful history. The well was in a high-activity area where 52 wells had been drilled previously in a township (approximately 36 sq miles). Example 11.1 illustrates a case in which this consideration was neglected in the earliest phase of well planning, which is data collection.Įxample 11.1 A turnkey drilling contractor began drilling a 9,000-ft well in September 1979. This design requirement must be adhered to rigorously in all aspects of the plan.

The well plan must be designed to minimize the risk of blowouts and other factors that could create problems. The second priority involves the safety of the well. Failure to stress crew safety has resulted in loss of life and burned or permanently crippled individuals. In some cases, the plan must be altered during the course of drilling the well when unforeseen drilling problems endanger the crew. Personnel considerations must be placed above all other aspects of the plan. Safety should be the highest priority in well planning. Unfortunately, it is not always possible to accomplish these objectives on each well because of constraints based on geology, drilling equipment, temperature, casing limitations, hole sizing, or budget.

The objective of well planning is to formulate from many variables a program for drilling a well that has the following characteristics: safe, minimum cost, and usable.

5 Preparation of Authority for Expenditures(AFE).

Attribute Changer 11.20b instal