ON SITE ESP REPAIR PAYS OFF IN INDONESIA

Joe D. Haines
Southeast Asia Corp. Applied Technics
Skiatook, Okla.

G.L. Langnes
Dragon Pacific Offshore Services PTE. Ltd.
Singapore

Harsoyo Hadipoetro
Petromer Trend Corp.
Kasmim Marine Terminal
Irian Jaya

Extensive production and use of electric submersible pumps (ESPS) in a remote region of Southeast Asia prompted Petromer Trend Corp., an oil company, to establish its own ESP repair facility.

The facility has met three defined objectives, and the scope of its work has been expanded. However, several elements must be present before such a remote operation can be successful.

This repair facility is at the Kasim Marine Terminal in Irian Jaya (Fig. 1). In 1970, Trend Exploration Ltd., operator for a joint venture group, signed a 30 year production-sharing contract with Pertamina, the Indonesian state oil company, covering an area in the Salawati basin of Irian Jaya.

Petromer Trend Corp. was established to operate the contract area, which initially covered 5,158 sq km of the Vogelkop area. This area is indicated in Fig. 1. It is almost 2,000 miles east of Jakarta and Singapore.

Petromer Trend's first exploration well resulted in the discovery of the Kasim 1 in 1972. Other wells followed but initial flowing oil production rates dropped rapidly as water moved into the oil zone through the high permeability vugular/fracture porosity. As reservoir pressures showed little decrease over time, it became apparent that the reservoirs were subject to a strong natural water drive. The water influx assumed control of the wells' producing capabilities.

In July 1975, the first ESP was installed in Kasim 6, to gain more fluid volume.

Petromer Trend reached its peak oil production of 100,313 bo/d on Nov. 15, 1976. Total fluid produced reached 214,112 b/d. By this time, seven oil fields had been discovered and put on stream.

THE NEED

Each year, more and larger ESPs were installed. By 1983, a gross fluid production rate of nearly 1.1 million b/d was reached. The oil production rate had dropped to around 34,000 bo/d. Purchasing standby equipment and repairing ESP units for this remote location had become a major logistic and economic problem.

Petromer was sending damaged or worn out equipment by boat to ESP manufacturers near Singapore for repair. In addition to the repair costs, another cost factor was the 2-4 month turnaround.

Petromer Trend determined that if the technology for repair and the spare parts were available, then it should analyze the possibility of on site ESP repair. The joint venture group approved the project in 1983, and the ESP repair facility was established at the Kasim Marine Terminal.

THE OBJECTIVES

The objectives of ESP repair were three-fold:

To decrease the operational costs by reducing repair, freight, and handling costs and by eliminating duties.
To increase the availability of the equipment. An on site repair shop would take only days to return a pump to service, whereas off site repair generally took about 4 months.
To continue the introduction of new technology and to develop the skills of the Indonesian staff.

NECESSARY ELEMENTS

For a remote repair program to be successful, three elements must be present: qualified personnel, repair technology, and personnel training capabilities.

In this case, "qualified" meant that persons working in the repair shop must have at least a high school education, an aptitude for mechanical and (to a lesser degree) electrical work, and a knowledge of English.

The latter is important because all instructions, diagrams, schematics, drawings, manuals, video cassettes, and slides are in English.

The willingness of the ESP manufacturers to provide repair know how and technology was crucial to establishing the repair facility.

It was also necessary in this case that they provide the initial training for repair of ESPS. Hands-on training was employed. In addition, training aids such as drawings, schematics, instructions, video cassettes, and slides were used.

An advisor was responsible for the supervision and continuation of the training program. The length of time the advisor was required depended on the rate of development of the personnel, the availability of tooling, and the support provided by the manufacturers.

A complete set of repair procedures was developed in-house at the Kasim Marine Terminal facility. They were based on information supplied by the manufacturers. These procedures were used to standardize the training and provide a basis for auditing the repair activities. The procedures are updated as the personnel become more experienced.

EXPANDED CAPABILITIES

Protectors, also known as seals, located between the motor and pump were the first components to be repaired. The protector prevents well fluid from entering the motor.

A small facility was adequate for disassembly, cleaning, inspection, assembly, and testing of the protector. During the initial training stage, one protector could be repaired in 12 hr. With experienced personnel and production techniques, a protector can currently be repaired in 6 hr. By the end of the first year, 55 protectors had been repaired. Since then, an average of 167 protectors have been repaired each year. Last year, from January through November, an average of 20/month were repaired.

The next phase of work undertook the mechanical repair of pumps, pump intakes, and gas separators. A new building, 50 ft wide, 100 ft long, and 25 ft high, was constructed for this phase of repair. It contains a 20 ft by 50 ft parts room and an office space. An overhead crane was installed to move pumps and motors the full length of the building. The crane can also load and move units outside the building.

The pump repair required an area 10 ft by 60 ft for a pump table. The pumps are disassembled on this table, and by using special tools and gauges, the stages are inspected for wear, corrosion, and erosion. During the initial training period, one pump was repaired per day. At present, the same personnel can repair two to three pumps per day. An average of 65 pumps are currently being repaired each year.

The third phase of ESP repair, the mechanical motor repair, calls for the disassembly of the motor, inspection, cleaning, quality analysis of salvageable parts, dry out of stator, assembly of motor, and testing before returning to the field. Depending on the availability of personnel to disassemble, clean parts, inspect, and reassemble, a motor can be repaired in 1-2 days. New tools and tables have been developed in-house to make the repair process more efficient.

The mechanical repair of the motor also requires electrical analysis of the stator and the assembled motor. Stators with no electrical problems are dried out before reassembly. A dry-out transformer has proved to be a more economical means of drying out the stators than the use of an oven. An oven has not been required because the transformer has been able to keep up with the number of stators being processed.

An area of 20 by 60 ft is used for the repair of the motors (Fig. 2). By the end of 1985, 15 motors had been repaired. Since then, an average of 110 motors have been repaired each year.

The final phase of repair, the winding of stators, started in January 1989. To provide space for winding, the building was extended 60 ft to an overall length of 160 ft. Inside the building extension, a 20 ft wide by 50 ft long winding room was built.

This room is air conditioned to control the humidity and to provide clean working conditions, which are essential for winding stators. A tower was constructed opposite the winding room to cover a test well drilled in the floor. In this test well, motors can be checked for vibration, amperage rating, coast time, etc. Pump rates and perimeters are also checked before installation in wells.

By using the pump table, the stator wire is pulled from the stator. Laminations are inspected for burned condition. If burned, then that section is pressed out by an hydraulic press and a new section pressed in. If the laminations check good, then housing and slots are cleaned thoroughly, and winding procedures commence. After the initial winding training, six stators per month were wound. After several months' training, production increased to 18 stators wound per month with only two experienced people and four trainees working. Figs. 3 and 4 show the facility after all its expansions to house the various repair services.

CROSS TRAINING

The cross training of personnel for various repairs has resulted in a continuing increase in the skills of the employees. Flexibility in scheduling repairs is an important by-product of the cross training. Certain personnel from the field installation group have been added to the repair team, and they have developed a better overall perspective of pump operation and pump repair.

Cable and switchboards are also maintained and repaired by the same personnel. Motor extension flat cables are fabricated at the repair site. Troubleshooting of surface and downhole equipment is also carried out by the field installation group, with a staff of 37 men.

The staff of the artificial-lift department repair facility comprises one superintendent, one expatriate consultant, one assistant superintendent, and one plant supervisor. In addition, there are three supervisors specializing in motors, pumps and protectors, and field installations. There is also one maintenance specialist and one logistics administrator, with two clerks and two partsmen. The additional members are craftsmen and trainees in their assigned sections.

At present, this repair facility services about 300 producing wells. The ESP department keeps a stock of ESP units repaired to ensure that production loss is minimized due to equipment down time.

ECONOMICS

Perhaps the most significant result of an ESP repair facility such as this one is the substantial savings that can be achieved. By acquiring parts economically through competitive bidding, taking advantage of local labor costs, and eliminating expensive freight and handling costs, expenses can be cut dramatically.

The comparison of on site repair cost vs. off site repair cost is presented in Tables 1, 2, and 3. As illustrated, there would be substantial savings from purchasing the stator (Table 1) to complete the motor repair; however, a larger savings can be accomplished by the on site winding of the stator and completion of the motor (Table 2). Also, there is a greater savings in on site repair of protectors. On site runs $400 vs. $2,164.

Table 3 illustrates the savings that can be accomplished by on site repair of pumps. This differential will vary with the wear, age, and well conditions that the pump has been subjected to.

Besides the above savings, the availability of repaired units has been much improved. Instead of taking 4 months to get an ESP returned to operation, only 1 week or less is now required. Also, it must be noted that the run-life of the on site-repaired ESP units is not only comparable to off site repaired units, but in some cases there is an increase in run-life due to less handling of units in transit.

This ESP repair facility had generated a total savings of $5 million by June 1989. Such an ESP repair facility provides a means of generating considerable cost savings, increased production, and overall increased efficiency of operation.