Wellbore Fluids Laboratory

Lab activity

Drilling fl uids laboratory is used in education and scientific research. Laboratory is equipped with instruments and devices that enable drilling fl uid preparation, drilling fl uid additives testing and determination of drilling fl uid properties according to API Spec 13A and recommended practice for laboratory testing of drilling fl uids RP 13B. The laboratory is used for the following: (I) determining the density of drilling fl uid, (II) conditioning the drilling fl uid, (III) determining the rheological properties of drilling fl uid at ambient conditions, (IV) determination of the viscosity of drilling fl uids at atmospheric pressure and temperatures up to 88 °C, (V) measuring the shear stress and the viscosity at diff erent shear rates, (VI) the calculation of rheological parameters of drilling fl uid in simulated downhole conditions, (VII) testing filtration under high pressure and temperature, (VIII) the determination of the coeffi cient of friction of mud and compare the quality of diff erent lubricants, (IX) determining the fi ltration of drilling fl uid at room temperature in conditions of elevated temperatures and pressures, and (X) determination of time of capillary absorption.

Head of laboratory: This email address is being protected from spambots. You need JavaScript enabled to view it., Prof, PhD

List of methods and procedures

Analytical procedure                                                                    Test method

Preparation of laboratory samples of mud

API standard

Determination of density mud

API standard

Determination of sand in the mud

API standard

Determination of solid particles, water and oil in the mud

API standard

Determination of filtration properties of drilling fluids

API standard

Measuring inflates rock samples in different fluids

API standard

Measuring the stability of emulsion mud

API standard

Making compacted samples rocks

API standard

Determination of time of capillary absorption

API standard

Examine the possibility of drilling fluid that creates a bypass to stijnkama wellbore

API standard

Determination of rheological properties of drilling fluids at high pressure and high temperature (260 ° C, 6895 kPa)

API standard

Testing of lubricating properties of drilling fluid

API standard

Examination of the possibility of a differential reception

API standard

Testing dispersion of debris rocks

API standard

Preparation of laboratory samples of mud

API standard

Small and medium-sized equipment

Name inventory          Tech. characteristics     Application                    Image 

Viscometer for testing of fluids under high pressures and temperatures - Model 1000

Working features:
Pressure : up to 6895 kPa (1000 psi)
Temperature: 260 °C

Shear Rate Range: 0,01 – 1700 s-1
Dimensions: 30 cm x 30 cm x 70 cm

Determination of drilling fluid filtration properties and fluid design.


Permeability Plugging Tester - PPT

Working features: Pressure : up to 13800 kPa
Temperature: 260 °C
Cell Volume: 500 ml
Dimensions: 38 cm x 63,5 cm x 107 cm

Drilling fluids rheological parameters determination.

Sposobnosti fluida

Determination of rheological properties of fluids

Working features: Temperature: Ambient temperature
Torque: 16,95 Nm
Ring rotational speed: 60 min-1
Dimensions: 48 cm x 38 cm x 36 cm

Determination of the lubricating quality of the drilling fluids.

Podmazivost isplake

Digital Viscometer – Model 900

Working features: Pressure : atmospheric
Temperature: up to 88 °C
Shear Rate Range: 0,01 – 1700 s-1
Dimensions: 44 cm x 23 cm x 14 cm 

Drilling fluids rheological parameters determination.

Digitalni viskozimetar

Differential Sticking Tester

Working features: Pressure : 3291 kPa
Temperature: ambient
Cell Volume: 200 ml
Dimensions: 15 cm x 15 cm x 46 cm

Determination of drilling fluids tendency to differential sticking.

Koeficijent ljepljivosti

Test Kit


Determination of the drilling fluid properties.

Svojstva isplake

Capillary Suction Timer

Working features: Temperature: Room temperature
Pressure: Atmospheric
Power: Battery 9V
Dimensions: 16,2 cm x 11 cm x 6 cm

Determination of the influence of electrolyte and/or polymer concentration on shale swelling inhibition.

Kapilarno upijanje

Roller Oven With Programmable Timer

Working features: Temperature: up to 232°C
Cell volume: 260/500 ml 
Rotational speed: 25 min-1

Aging of the drilling fluids under static or dynamic conditions and from ambient to highly elevated temperature.

Kondicioniranje isplake 1

Kondicioniranje isplake 2

Dynamic Linear Swellmeter Complete with Compactor

Working features: Temperature: up to 480°C
Pressure: atmospheric
Cell volume: 160 ml 
Rotational speed: 1100 min-1
Samples Compaction Pressure: up to 68,9 MPa

Drilling fluid optimization.

Bubrenje isplake 1

Bubrenje isplake 2

Electrical Stability Meter

Working features: Pressure: atmospheric
Temperature: Ambient temperature
Power: Battery 9 V

Determination of the oil mud emulsion stability.

Stabilnost uljne isplake

pH Meter

Type: pH135i; measurement range: pH = -2 up to +16; U (mV)
= -1999 up to + 1999; T (°C) = -5 up to +105; calibration
standards: pH 4, 7 and 10; electrode storing solution KCl.

Drilling fluids testing, environment protection; pH chek-out in the various chemical analyses.

Ph metar


Temperature: 50-200°C; 220V, 500W.

Determination of humidity in soil and sediment samples;
determination of crystalline water in geological material samples;
sample preparation for analysis carried out at the Petroleum
Engineering Department.



200W, 220V, 4000 rpm

Sample preparation for chemical, granulometric and other analysis carried out at the Petroleum Engineering Department.

Centrifuga Tehnika


Rotation speed: 
1) 3 speeds – 13000, 16000, 18000 rpm,
2) 1 speed – 11000 rpm,
3) 2 speeds – 4000 i 12000 rpm.

Preparation of drilling fluid for testing.


Brookfield viscometer

Environmental conditions:  

temperature: room temperature

range of shear rates:
0,01 s-1  – 245 s-1

Determination of the viscosity (in particular the value of LSRV fluids).

Brookfield viskozimetar