Chart Recorder for RPVOT (RBOT) Oxidation Stability Bath

Rotating Pressure Vessel Oxidation Testing Equipment

Professional laboratory apparatus for measuring oxidation stability of petroleum products, steam turbine oils, mineral insulating oils, and gasoline automotive engine oils using RPVOT (RBOT) and TFOUT methodologies. The system provides rapid determination of oxidation stability under severe test conditions.

Complete System Configurations

Available in 2, 3, and 4-unit configurations featuring the Oxidata Pressure Measurement System for electronic pressure monitoring. These complete systems conform to ASTM D2112, D2272, D4742 and IP 229 specifications.

Test Methodology

The RPVOT (RBOT) procedure employs severe oxidation conditions suitable for both new and in-service petroleum oils. Samples are oxidized in the presence of water and a copper catalyst within a stainless steel pressure vessel under an initial pressure of 90psi (620kPa). Pressure inside the vessel is recorded while the vessel rotates at 100rpm at constant temperature. The oxidation stability is determined by measuring the time required for a specified pressure drop. The TFOUT method represents a variation of this procedure specifically designed for gasoline automotive engine oils.

Oxidation Bath Units

Constant temperature baths rotate oxidation pressure vessels at 100rpm at a 30° angle in accordance with ASTM specifications. These units include drive system and oil bath with electronic solid state temperature control, meeting ASTM requirements for heat transfer capability and temperature control precision.

A convenient carriage arrangement enables quick and secure insertion of oxidation vessels into the drive system. Strong magnets hold vessels in place while locating pins engage the vessel base. PTFE guides support the pressure vessel stem for stability. The magnetic carriage releases automatically if obstruction occurs to prevent damage. Chain and sprocket drive systems powered by heavy duty capacitor start motors rotate vessel carriages at 100rpm. Drive shafts ride on PTFE fluorocarbon bearings compatible with silicone heat transfer fluids and other bath oils.

Bath temperature is controlled within ASTM specified limits by electronic solid state controllers with °C/°F switchable digital setpoint and display. Overtemperature protection automatically interrupts power when bath liquid temperature exceeds 16.7°C (30°F) above the temperature setting or 177°C (350°F). Power must be manually restored after checking the cause. Pressure vessel carriage vanes circulate bath oil during testing to ensure temperature uniformity, and auxiliary stirrers can operate between tests to prevent sludging of non-silicone bath oils.

Bath interiors are constructed of welded stainless steel and fully insulated. Hinged cover sections provide easy access to vessel carriages. Vapor barriers in covers close around vessel stems to contain vapors from hot bath medium. Chemical resistant polyurethane finish protects bath exterior and control cabinet.

Bath Specifications

Bath Models

Oxidation Pressure Vessels

Polished stainless steel construction capable of conversion for TFOUT method use. Each vessel consists of pressure vessel body, cap and stem with inlet needle valve in accordance with ASTM specifications. Vessels hold one borosilicate glass sample container between two PTFE discs. Closure rings tighten by hand to seal cap to pressure vessel body. Vessels connect to pressure recorder or rotary transducer and rotate on magnetic carriage in RBOT bath. Withstand working pressure of 500psi (3450kPa) per ASTM specifications. Stainless steel construction ensures proper heat transfer rate. Closure rings are constructed of chrome plated steel. Includes PTFE fluorocarbon wear disc and sample container cover disc.

Oxidata Pressure Measurement System

Complete electronic measurement systems for plotting pressure versus time and temperature in RPVOT (RBOT) and TFOUT testing. Each system includes transducers, bomb couplings, RTD probe assembly, multiplexer, data acquisition card, software, and mounting and connecting hardware. Available in two, three and four pressure vessel configurations, with additional channels expandable to a total of twelve pressure and four temperature channels.

Key Features

• Electronic pressure measurement exclusively designed for RPVOT (RBOT), TFOUT and other ASTM oxidation test methods
• Powerful Oxidata software for Windows and Windows 95 environments
• Monitors up to twelve pressure and four temperature channels
• Can be installed to most manufacturer's RPVOT(RBOT)/TFOUT test apparatus
• On-line, real time monitoring of up to twelve samples simultaneously with results plotting directly to screen for instant monitoring or printout
• Menu options for RPVOT (RBOT) or TFOUT testing, as well as other ASTM fuel and lubricant oxidation tests
• Programmable automatic end point detection with graphical and tabular representation
• Each channel configurable and operable independently with different start/stop times and different ASTM test methods
• Zoom in feature allows magnification of any plot sector on any channel for detailed study
• Monitors and reports temperatures of as many as four baths simultaneously using accessory RTDs, calculates and displays average temperature for each bath
• Exports data to spreadsheet programs such as Microsoft Excel, Lotus 1-2-3
• Temperature and pressure calibration capability
• Data saved directly to hard drive during testing to prevent loss of valuable data
• Operates in Windows 2000 or higher
• Simple upgrade from existing Koehler data acquisition systems

Included Accessories

• Rotary transducers (connects directly to bomb)
• Data acquisition box with USB interface
• Oxidata software
• Multiplexer
• RTD probe assembly (1)
• Mounting Bracket for bath
• Connecting cables and hardware

Computer Requirements

System Models

Oxidata Retrofit Kits

To upgrade existing DOS-based Koehler electronic pressure measurement systems to the Oxidata system. Kits include Oxidata software, data acquisition card, multiplexer board, RTD probe assembly and connecting cables. Does not include rotary transducers or bath mounting bracket.

Retrofit Kit Accessories