Oil&Gas: Gasunie ZDW-A1A & – A1B Workover

Workover operations on ZDW-A1A & ZDW-A1B

Start: 23 March 2020
End: 5 June 2020

Objective: Integration of cavern A1 into the existing underground gas storage

Depth (AH): 1395m
Depth (TVD): 1392m

Project Summary

Client:N.V. Nederlandse Gasunie (EnergyStock)
Location:Zuidwending
Wells:ZWD-A1A & ZWD-A1B
Start operations:23 March 2020
End operations:5 June 2020
Objective:To integrate the cavern A1 into the existing underground gas storage (Aardgasbuffer Zuidwending). There are two wells in this cavern, ZWD-A1A and ZWD-A1B and both wells needed to be equipped with a gas well completion.
Result: The project was completed successfully.
Depths (AH):1394.5 m
Depths (TVD):1391.5 m
Role of WEP:Well site supervision (day and night shift) and engineering provision.
Challenges:Complex completion system, composed of a welded 9-⅝” production casing and packers which required specific and detailed welding and completion assembly procedures.
New Technology:Not applicable

Project Description

Gasunie intends to integrate the cavern A1 into its existing underground gas storage (Aardgasbuffer Zuidwending). There are two wells in the cavern that needed to be equipped with a gas well completion. Within the new completions a permanent packer and a subsurface safety valve are installed on both wells. The welded completions will be hung-off in tension on the tension head. Well ZWD-A1A is equipped with a long tailpipe that extends to the bottom of the cavern. The working program covered the major working steps to be performed for the installation of the completion in the wells ZWD-A1A and ZWD-A1B.