Estimating cuttings removal
AssigneeStatoil Petroleum AS
InventorsMorten Lien, André Holm
Life of this patent
Estimating the term…
Abstract
A first property, derivable from mass, of a drilling fluid is measured at a point upstream of a cuttings removal device. A second property (also derivable from mass) is measured at a point downstream of the cuttings removal device. A difference between the properties is determined over a period of time to obtain an estimate of the rate of cuttings removal. This allows the property of the drilling fluid before and after cuttings removal to be compared to give an indication of the rate of cuttings removal, which is indicative of the borehole cleaning.
Claims24
A method of determining a flow velocity of a drilling fluid in a tubular, the method comprising the steps of:
- measuring a property derivable from mass of the drilling fluid at a first location and determining a first time at which a variation in the property is detected;
- measuring the property derivable from mass of the drilling fluid at a second location, the second location being located downstream of the first location, and determining a second time at which the variation in the property is detected;
- and
- determining the flow velocity using the determined first and second times.
An apparatus arranged to determine a flow velocity of a drilling fluid in a tubular, the apparatus comprising:
- a first device arranged to measure a property derivable from mass of the drilling fluid at a first location and determining a first time at which a variation in the property is detected;
- a second device arranged to measure the property derivable from mass of the drilling fluid at a second location, the second location being located downstream of the first location, and determining a second time at which the variation in the property is detected;
- and
- a computer device arranged to determine the flow velocity using the determined first and second times,
- wherein any of the first and second devices are located on a low pressure riser.
A method of estimating a rate of cuttings removal from a borehole, the method comprising the steps of:
- making a first measurement of a property derivable from mass of a drilling fluid including cuttings upstream of a cuttings removal device;
- making a second measurement of a property derivable from mass of the drilling fluid downstream of the cuttings removal device after the cuttings have been removed;
- and
- determining a difference between the first and second properties over a period of time by subtracting the second measurement from the first measurement to obtain an estimate of the rate of cuttings removal.
An apparatus arranged to estimate a rate of cuttings removal from a borehole, the apparatus comprising:
- a first property measurement device arranged to measure a property derivable from mass of a drilling fluid including cuttings upstream of a cuttings removal device;
- a second property measurement device arranged to measure a second property derivable from mass of the drilling fluid downstream of the cuttings removal device after the cuttings have been removed;
- and
- a computer device arranged to determine a difference between the first and second properties derivable from mass over a period of time by subtracting the second measurement from the first measurement to obtain an estimate of the rate of cuttings removal.
A method of detecting a kick in a flow of drilling fluid in a tubular, the method comprising the steps of:
- continuously or periodically measuring a property derivable from mass of the drilling fluid within the tubular, the property derivable from mass being selected from any of mass, weight, specific gravity, specific weight and density;
- and
- detecting a variation in the property of more than a predetermined amount over a predetermined time period to directly detecting the kick in the flow of drilling fluid.
Dependencies are inferred from the claim text.