Tag Archives: Well Control Equipment

Casing pressure must be maintained constant while bringing the pump to speed. If the pressure increases more than SICP, the bottom hole pressure will increase.

If the first circulation of the driller’s method is successful, SIDPP and SICP must be the same.

Because of lighter fluid density in the annulus, casing pressure is usually higher than drill pipe pressure.

The influx will be longer in a small hole therefore it will result in higher casing pressure.

Equivalent Circulating Density (ECD), ppg = Current Mud Weight + (Annular Pressure loss ÷ 0.052 ÷ TVD)

Equivalent Circulating Density (ECD), ppg = 10 + (300 ÷ 0.052 ÷7500) = 10.8 ppg

HCR and Rams Preventer ( Pipe Rams, VBR’s, Shear Rams, Blind/Shear Rams) are operated by manifold pressure.

API RP53 recommends 2 times usable accumulator volume.

With normal 3000 psi system, you should see the following figures on pressure gauges:
Rig air gauge = 100 psi
Manifold gauge = 1,500 psi
Accumulator gauge = 3,000 psi
Annular gauge = 500- 1,500 psi

When the air pressure is o psi, you will not be able to operate the BOP from the remote panel.

The mud leg column must be re-established before the gas will stop blowing through.

Weep holes have the primary function to tell people that the mud seal on the piston rod is leaking or not.

Gas migration rate (ft/hr) = Increase in pressure (psi/hr) ÷ mud gradient (psi/ft)

Increase in pressure = 200 psi/hr
Mud gradient = 0.052 x 12.5 = 0.65
Gas migration rate (ft/hr) = 200÷0.65 = 308 ft/hr

Ref: Estimate gas migration rate in a shut in well

Two factors when selecting BOP elastomer composition are type of drilling mud and temperature rating of elastomer.

There are two fluid contributing in the hydrostatic pressure against the loss zone which are water and mud. Therefore, you need to determine hydrostatic pressure of each fluid and the summation is the pressure at the loss zone.

Height of 60 bbl water = 60 bbl ÷ 0.0455 = 1,319 ft.
Hydrostatic pressure of water  = 0.052 x 8.6 x 1,319 = 590 psi

Height of mud = 9,000 – 1,319 =7,681 ft
Hydrostatic pressure of mud = 0.052 x 12.0 x 7,681 = 4,793 psi

Total hydrostatic pressure  = 4,793 + 590 = 5,383 psi.

The safety valve must be in opened position.

Most likely from this case is choke wash out because the casing and drill pipe pressure keep decreasing without changing pump rate.

RX and BX gaskets are wellbore pressure assisted gaskets.

Water is recommended fluid for BOP test because it has less compressibility.

Two advantages of installing the float valve are prevent kick into the drill string and prevent bit plugging.

The operating pressure depends of the leg height and mud weight in the mud gas seperator.

Pressure = 0.052 x leg height x MW
Pressure  = 0.052 x 15 x 13 = 10 psi

The disadvantage of the IBOP is that you cannot run wireline through because there is a check valve inside its body.

The ring gaskets are only one time use. Do not re-use it.

The BOP test must not exceed 21 days according to API.

This indication shows that the bit nozzle is plugged because drill pipe pressure increases but there is no change in casing pressure. Driller does’t need to make any adjustments. He needs to keep circulating with new circulating pressure at 1,600 psi.

Maximum temperature limit of annular preventer is 180 F.