Expro has over two years TCP/DST contractual experience with a National Oil Company (NOC). They wanted us to test an exploratory zone in a production well before putting this additional zone into production
The initial plan was to perforate the zone with wireline and perform DST with provision for proppant fracturing in case the well did not flow naturally
Expro reservoir engineers analysed the reservoir data and observed that the combination of permeability, low reservoir pressure and positive skin would stop the well flowing naturally
Expro recommended perforating the underbalanced zone using TCP to reduce or remove the skin effect; thus allowing the well to flow naturally
Expro Excellence
Expro designed the TCP system to achieve dynamic underbalanced perforation using a TCP/DST string in static underbalanced well condition
The zone was perforated using a hydraulic delay firing head and the well started flowing naturally
The downhole gauge data was analysed and pressure derivative showed negative skin which was achieved with the help of 700 psi static underbalance and 300 psi dynamic underbalance during perforation
Value to Client
Underbalanced TCP perforation allowed the well to flow naturally, which avoided the additional cost of stimulation
This solution saved additional costs and time associated with multiple wireline runs to perforate the well
A single run of TCP/DST string, provided data to the client which helped them make informed future decisions