STAVANGER, Norway– Through use of the PWC (perforate, wash, and cement) plug and abandonment method (P&A) on the Valhall field, HydraWell has helped Aker BP execute its plugging program faster than planned.
Since May 2017, HydraWell has contributed toward plugging 10 shut-in wells on the original drilling platform (DP) at the Valhall field center.
Compared to the first P&A phase on the DP platform from 2014 to 2016, Aker BP has reduced the average time per well by 50% in the latest phase, despite a rise in the complexity of the wells toward the end of the campaign.
Plugging wells on the DP platform is a key part of the work to modernize the Valhall field center. The three original platforms from when the field started producing in 1982 – QP, DP, and PCP – will be removed. Four wells remain to be permanently plugged prior to the removal of the DP platform.
Martin Straume, drilling engineering manager P&A, Aker BP, said: “We have significantly reduced the execution time of our P&A operations through improving a number of elements. HydraWell’s PWC technology, with HydraHemera in front, is one such element. Among other things, we have run computer simulations to identify how much time we need to wash the back of the casing before the cementing starts. This has improved our understanding and means that we can do things faster than before.”
“In addition, together with HydraWell we have started running one-trip systems on applicable wells. This means that we drop the perforation gun into the well instead of pulling it back up before we start washing. This has contributed towards reducing execution time significantly,” Straume adds.
The company’s HydraHemera PWC system perforates the well before washing the casing and then setting the cement plug – a so-called rock-to-rock barrier that is required under the Norsok standard. Through this method a rock-to-rock barrier can be installed in less than two days. The technology can be used on both single and dual casing wells.