Autoclave for Dynamic Corrosion Testing

Autoclave for Dynamic Corrosion Testing

The autoclave is used to evaluate the corrosion rate and effectiveness of various inhibitors used in the oil and gas industry. Experiments using the autoclave allow for the evaluation of material, coating, or inhibitor characteristics, analysis of corrosion damage to samples with weight loss coupons, and electrochemical studies in aggressive high pressure and high temperature environments, which represent conditions encountered in field conditions in the oil and gas industry.

Key characteristics include:

• Internal volume of the empty vessel: 2 liters
• Internal length of the vessel: 227 mm
• Internal diameter of the vessel: 106 mm
• Vessel material: C276 Hastelloy
• Closure with detachable clamp and PTFE gasket: 5 pieces
• Design temperature: 350°C
• Operating temperature: 310°C
• Design pressure: 250 bar
• Operating pressure: 210 bar
• Total weight of the autoclave: 20 kg
• Total weight of the set: 55 kg

Environment Characteristics:
• Working environment in liquid phase: mineralized, aggressive waters of the oil field;
• Working environment in gas phase for pressure creation: CO2, N2, H2S (H2S content not less than 30% of the total gas volume).

The autoclave is made from a solid bar without using welding. The rotating cell is made in accordance with ASTM G170; for the autoclave base, stainless steel grade 304L and aluminum 1060 are used for all aesthetic (visual) details. The autoclave is equipped with an explosion-proof polycarbonate housing with protection against overheating, which is bolted to the laboratory stand. The autoclave can simultaneously test up to 8 witness samples (coupons). The cell rotates due to a magnetic coupling drive. The magnetic coupling rotates due to an electric motor. The rotation speed is up to 2,000 rpm. The device is equipped with certified gauges, valves, fittings, temperature probes, and other peripheral equipment.

The safety of the autoclave is ensured by the use of rupture membranes and pressure relief valves. All elements that come into contact with the environment are made of C276 Hastelloy material.

The autoclave uses a built-in heater with insulation for heating. Power is 1.5 kW, 220V, 1 phase. An embedded PLC with an advanced PID temperature controller and a touch screen is used to control the system. The operation of the autoclave is controlled through software. The software is used to set the working parameters and to record experiment data.

Type of Autoclave: Installed on a frame, with a fixed mounted cover and a movable vessel.

There is a built-in dosing system for chemical reagents into the flow.

The reactor cover has ports for gas inlet and outlet, as well as liquid inlet and outlet. Each port is equipped with a needle valve.
• The gas inlet port from the low-pressure manifold is equipped with a low-pressure transducer.
• The gas outlet port to the manifold (vent) is equipped with a needle valve.

The reactor bottom has ports for gas inlet and outlet, as well as liquid inlet and outlet:
• A ball valve for liquid drainage.
• A needle valve for gas inlet.

The low-pressure gas relief manifold combines the gas discharge from the fine adjustment valves and the emergency relief valve into the atmosphere.

An emergency relief valve is used to release excess pressure in the gas phase. The discharge is carried out through a bypass line to the low-pressure gas relief manifold (atmosphere or ventilation system). The valve is calibrated at the factory to a specified pressure.

The safety system consists of the following components:
• C276 rupture disc holder (alloy 400 rupture disc with PTFE coating);
• Pressure relief valve for rupture disc protection;
• Wired overheat alarm for independent heater and system shutdown; software shutdown and program cancellation (depending on temperature and pressure); protection against overheating and overpressure and relief of the rupture disc; H2S gas detector; input voltage of 100-240 V AC; protection against overvoltage and power overload.

The delivery set includes:
• 5 gate valves with detachable clamps and PTFE gaskets;
• High-pressure electrochemical Ag/AgCl HPHT probes that can withstand temperatures up to 305 °C and pressures up to 138 bar;
• A Pt sensor;
• pH sensors based on ZrO2 that can withstand temperatures up to 343 °C and pressures up to 138 bar, with a C276 housing material;
• An internal holder for 8 witness samples (coupons);
• 76.2x12.7x1.5 mm witness samples (coupons) made of St.20 – 100 pcs.;
• A system for sampling water from the solution in the system;
• A chemical reagent dispenser for dosing into the flow of 2-1000 μl;
• A data acquisition system based on temperature and rotation speed control, as well as pressure control (computer, display, control panel, software, etc.);
• Tools, fittings, valves, adapters, sensors, extensions, and other installation components for starting and operating the device;
• A 1-channel dispenser for 10-100 μl;
• A power filter for connecting the device and control station;
• A system for deaerating the test environment (a vacuum diaphragm pump);
• A torque wrench (10-110 Nm);
• A table for the complex. The table is equipped with a ventilation box extension, and the ventilation is connected to the table via a Ø200 mm duct. The front of the box is covered with transparent rolling shutters. The working chamber is equipped with LED lighting; the working zone has a supply of washing water and compressed air. The lower part of the complex table provides space for auxiliary equipment. The working zone is equipped with an operator control panel for gas/liquid discharge, automation and measurement means;
• A programmable logic controller with expansion modules;
• A low-pressure transducer of 0-2 atm (working part material: SS316L), installed in the reactor lid;
• A high-pressure transducer of 0-250 atm (working part material: SS316L), installed in the reactor lid;
• A resistance thermometer sensor (mounted in the lid or bottom of the reactor, specified when configuring the internal filling of the reactor), with a stainless steel protective sleeve material;
• A temperature sensor on the surface of the heater;
• An analog pressure gauge (accuracy class 1.0), with a working part material of 12X18H10T, installed in the reactor lid;
• An emergency warning system, an emergency stop button, a SCADA system with audio-visual alarms (logging data on heating, cooling, pressure, time, display of graphs, and experimental parameters);
• Pneumatic distributors, two-handed switching, and automatic shut-off valves.

Parameters subject to automatic control:
• Temperature (PID control)
• Agitation (direction of rotation, set/factual speed, drive load/torque)
• Start/end time of experiment

Accuracy of parameter control:
• Temperature: ±0.5 °C, resolution 0.01 °C
• Pressure: at PVI of 1 atm and 200 atm, main error 0.1% of the sensor's measurement range
• Agitation: ±5 rpm

Parameters subject to manual control:
• Pressure (regulated by gas and liquid flow method)

To display process information, a 10-inch touch panel is installed for the operator.
Pneumatic cylinders with manual control (dual control) are installed to control the height of the reactor lid.
The reactor is heated with a clamp-on electric jacket, and forced air cooling is used to cool the heating jacket of the reactor. The cooling agent is air, and the cooling temperature is equal to the ambient temperature. The power supply voltage is 380 V 50 Hz, and the maximum power consumption of the system is 6 kW.

A compressor with an air preparation unit is used to operate the pneumatic cylinders for lifting the reactor lids and connecting the blowing gun. The working pressure is 0-8 atm, and the performance is 220 l/min.

Type of connection to the water supply system: 1/2 inch thread.