Determination of bottomhole data based on wellhead data in fontan wells according to mining data

2. Methodological part: In suspended gas wells, the bottom pressure is determined by means of a depth manometer or the wellhead is determined statically with the help of a manometer. At this time, if the flow to the well is completely stabilized, then the calculated or measured pressure is taken equal to the formation pressure. If the well bottom pressure is not equal after closing the well within a certain time, or if it is technically impossible to close the well, then the well bottom pressure is found by means of reporting. The bottomhole pressure in a suspended well is determined by the following formula:
P_q=P_a

Or
P_q =P_a e^B

Here

P_q and P_a - is the pressure of the bottom of the well and the wellhead;

L- is the depth of the well;
⍴- is the depth of the well;;
Z_or- is the gas compressibility coefficient. This parameter is set at medium pressure and temperature.
The reporting technology for this is done as follows.
1) The average temperature is determined based on the temperature of the bottom of the well and the mouth of the well (reservoir temperature):

T_or =

Here T_q and T_a - the bottom of the well and the temperature of the wellhead.

T_q=63°C+N°+273=K°

T_a=23°C+N°+273=K°

2) Based on the received values, the critical pressure and temperature are determined:

P_gət =
and
T_gət
Here
P_böh= 47.6 kq/sm²
and
T_böh=218.37°K

Based on the given values, the Z_or price is determined:

Z_or=1-10-2(0.76T³_gət=9.36 T_gət +13) (8-P_gət) P_gət

3) The relative density of the gas is determined;

4) Based on the prices received:

5) Well bottom pressure is determined by the following formula:

P_q=P_a e^B

6) To refine the report, the following operation is performed:

P_or= P_a( )

7) According to the obtained P_or the pressure brought by knowing T_or again is determined:

P’_gət =

T’_gət

8) Based on the calculated values, Z'_or is calculated:

Z’_or=1-10-2 (0.76 T³_gət-9.36 T’_gət+13 ) (8-P_gət) P_gət

9) Now let's calculate the top parameter:

B’=

10) Based on these values, the well bottom pressure is determined:

P’_q= P_a e^B’