Sand erosion detection by In-service Ultrasonic Testing to prevent hydrocarbon leak at wellhead choke valve in Handil Field – Pertamina Hulu Mahakam

Abstract

Handil field is a mature oil field located in the Mahakam delta that has been in production since 1975. Following its natural decline, sand production management is a challenge that cannot be avoided to sustain the Handil field oil and gas production.

About 65% of Handil field production comes from a high-risk sand production well category. As part of the sand production monitoring strategy, the choke valve verification program is carried out regularly to identify the erosion due to sand which may lead to hydrocarbon leaks. However, this approach has a few limitations and requires a well shut down.

This paper discusses a new method to detect sand erosion at the choke valve by using an In-service Ultrasonic test (UT) implemented in the Handil field. In-service choke inspection by Ultrasonic Testing (so-called iCIUT) is an innovation implemented to avoid hydrocarbon leaks due to sand erosion by early detection of the erosion sign and potential escalation at the internal part of the wellhead choke without production losses impact.

A new methodology to improve the existing manual choke verification is introduced in 2019. This method promotes the utilization of ultrasonic testing to resolve the limitations to identifying erosion of the inaccessible internal part of the choke valve. The ability to conduct in-service inspection provides a valuable benefit to avoid the need to shut down the well and production losses during the operation.

This innovation has successfully identified a defect at the wellhead choke valve in more than 40 wells in the Handil field since 2019. It’s been proven capable of detecting erosion at the wellhead choke valve in advance, so hydrocarbon leaks can be prevented. The iCIUT method demonstrates advantages as follows:

• Provides simple operation without the requirement for unit dismantling and a lifting equipment.
• No production losses during the operation.
• Estimate choke valve service life and replacement time.

This iCIUT method opens an opportunity and low-cost operation to optimize production from shallow zone when a limited option is available for sand control installation or high-cost sand-resistant materials. On the other hand, it improves well operational efficiency and HSE wise.