AZA 0946 CENTRIFUGE EXTRACTOR (MOTORISED)

Description

The AZA 0946 Motorised Centrifuge Extractor from AZALAB is a fundamental and widely utilized laboratory instrument for the quantitative determination of bitumen (asphalt) content in hot-mixed bituminous paving mixtures and pavement samples. This motorised version offers significant advantages over manual extractors by providing automated, consistent, and highly precise control over the extraction process, which is crucial for achieving accurate results. In India, where vast road networks are continuously being developed and maintained, ensuring the correct bitumen content in asphalt mixes is paramount for the quality, performance, and longevity of the pavement.

The working principle of the motorised centrifuge extractor is based on solvent dissolution combined with centrifugal force. A known weight of the bituminous mixture is placed inside a removable, precision-machined aluminum rotor bowl. A suitable solvent (such as trichloroethylene, methylene chloride, or n-Propyl Bromide) is introduced into the bowl to dissolve the bitumen binder. As the bowl rotates at high speeds, the centrifugal force drives the bitumen-solvent solution through a filter paper (placed between the bowl and its cover) and out through a drain, while retaining the aggregate particles within the bowl. This process is repeated with fresh solvent until the aggregate is thoroughly washed and visibly clean. The collected solvent-bitumen solution can then be further processed, often using a solvent recovery unit (like AZA 0949), to reclaim the solvent for reuse and, if necessary, recover the bitumen for additional testing. The aggregate remaining in the bowl is then dried and weighed. The bitumen content is determined by calculating the difference in weight from the original sample, accounting for any moisture and mineral matter.

The AZA 0946 Motorised Centrifuge Extractor is distinguished by its automated operation. It consists of a robust motor directly coupled to the rotor bowl, enclosed within a sturdy cylindrical aluminum housing. A separate control panel, typically featuring an electronic card with an AC drive, allows for precise control of the bowl’s rotation speed. This advanced control system automatically ramps the speed from 0 up to 3600 R.P.M. (revolutions per minute) as specified by the relevant standards, and includes an automatic fast stop mechanism at the end of the test. A digital display monitors the frequency and speed, enhancing operational precision and ease of use.

Applications and Compliance of the AZA 0946 Motorised Centrifuge Extractor

The AZA 0946 Motorised Centrifuge Extractor is an indispensable tool for quality control and research in the field of civil engineering, particularly in the construction of flexible pavements in India. Its adherence to internationally recognized standards ensures reliability and comparability of test results.

Key Features that enhance its performance and utility:

• Automated Speed Control: The electronic control with AC drive ensures a smooth, consistent, and precise acceleration and deceleration of the rotor bowl, minimizing disturbance to the aggregate fines and improving extraction efficiency.
• High Precision Machined Bowl: The removable aluminum rotor bowl is precision-machined and balanced to ensure stable high-speed rotation, preventing vibrations and ensuring accurate separation.
• Robust Construction: Housed in a durable cylindrical aluminum box, the unit is built to withstand rigorous laboratory use and the corrosive effects of solvents.
• Safety Features: The enclosed design contains solvent vapors and splashing, while the automatic fast stop function and the overall robust build contribute to a safer working environment.
• Digital Display: Provides real-time monitoring of speed, allowing operators to adhere strictly to testing protocols.
• Made in India: This ensures easy availability of spare parts, local technical support, and compliance with regional supply chain requirements for Indian laboratories and projects.

Primary Applications in India:

• Quality Control in Road Construction: The most crucial application is ensuring that the bitumen content in asphalt mixes produced for road construction meets the specifications laid down by authorities like the Ministry of Road Transport & Highways (MoRTH). Incorrect bitumen content can lead to premature pavement distresses such as rutting (too much bitumen) or cracking/ravelling (too little bitumen).
• Mix Design Verification: Used by consultants and contractors to verify the asphalt mix designs before mass production and during batching to ensure consistency.
• Aggregate Grading Analysis: After bitumen extraction, the recovered aggregate can be used for sieve analysis to determine its gradation, which is another critical parameter for mix performance (as per IS 2720 Part 4 and related standards for aggregate testing).
• Research and Development: Employed in R&D laboratories for developing new asphalt mixes, evaluating different types of binders, or studying the performance characteristics of various aggregate-bitumen combinations.

The AZA 0946 Motorised Centrifuge Extractor complies with critical standards for bitumen extraction:

• ASTM D2172: Standard Test Methods for Quantitative Extraction of Asphalt Binder from Asphalt Mixtures. This is the primary international standard governing this test.
• AASHTO T-58 & T-164: These are American Association of State Highway and Transportation Officials standards that also cover bitumen extraction methods.
• Indian Standards (IS): While no direct single IS standard for the “motorised centrifuge extractor” specifically is typically cited for the equipment itself, the method of bitumen extraction and subsequent aggregate analysis aligns with principles outlined in various parts of IS 2720 (Methods of Test for Soils), particularly when the recovered aggregate is subjected to sieve analysis (e.g., IS 2720 Part 4: Determination of Grain Size Analysis). The acceptance of ASTM D2172 in many Indian project specifications and laboratory accreditations means that equipment conforming to it is widely used and accepted in the Indian context.

Operating the AZA 0946 involves preparing the asphalt sample, placing it in the bowl with filter paper, adding solvent, and running the motorized extractor through cycles until the solvent runs clear. The aggregate is then dried and weighed. Regular maintenance includes thoroughly cleaning the bowl and housing after each use, replacing filter papers, and periodically checking the motor and control panel for optimal functioning.

Specifications

• Model Number: AZA 0946
• Test Method: Quantitative Determination of Bitumen Percentage by Centrifugal Extraction (Motorised)
• Operation Type: Motorised / Automatic
• Capacity Options: Available in 1500 g or 3000 g sample capacities.
• Rotor Bowl: Removable, precision-machined aluminum rotor bowl.
• Housing: Cylindrical aluminum box/housing.
• Motor: Electric motor with AC drive.
• Speed Control: Electronic control panel with variable speed ramp from 0 to 3600 R.P.M. (revolutions per minute).
• Speed Monitoring: Digital display monitoring frequency/RPM.
• Safety Features: Automatic fast stop bowl rotation at the end of the test.
• Power Supply: 230 V A.C., Single Phase, 50 Hz.
• Standard Compliance: Conforms to ASTM D2172, AASHTO T-58, T-164.
• Country of Origin: Made in India.
• Included Accessories (Typical):
  • Precision-machined aluminum rotor bowl (1500g or 3000g capacity, as ordered).
  • Rotor bowl cover.
  • Collecting pan/receiver.
  • Spanner for locking nut.
• Optional/Consumable Accessories (Typically purchased separately):
  • Filter paper discs for centrifuge extractor (e.g., AZA 0945-A filter paper discs).
  • Suitable solvents (e.g., Trichloroethylene, Methylene Chloride, n-Propyl Bromide).
  • Solvent Recovery Unit (e.g., AZA 0949).
  • Drying oven for aggregate.
  • Electronic Balance for accurate weighing.

FREQUENTLY ASKED QUESTIONS (FAQ)

Q1: What is the primary purpose of the AZA 0946 Motorised Centrifuge Extractor? A1: The AZA 0946 Motorised Centrifuge Extractor is used for the accurate determination of the bitumen (asphalt) content in bituminous paving mixtures.

Q2: What is the main advantage of the motorised version over a hand-operated one? A2: The motorised version provides automated, consistent, and precise control over the rotation speed and duration, eliminating manual effort, reducing operator fatigue, and leading to more reproducible and accurate results.

Q3: What are the key standards that the AZA 0946 complies with? A3: The AZA 0946 complies with prominent international standards including ASTM D2172 and AASHTO T-58, T-164, which are widely accepted for bitumen extraction testing.

Q4: What capacity options are available for this extractor? A4: The AZA 0946 is typically available in 1500 gram or 3000 gram sample capacities, catering to different project and sample size requirements.

Q5: Is filter paper required for this extractor? A5: Yes, unlike filterless models (like AZA 0947), the AZA 0946 Centrifuge Extractor (Motorised) typically requires the use of filter paper discs to separate the dissolved bitumen from the aggregate fines during the centrifugal process.

Q6: How does this equipment contribute to road construction quality in India? A6: By providing a precise and efficient method for determining bitumen content, the AZA 0946https://azalab.com/aza-0946-motorised-centrifuge-extractor Motorised Centrifuge Extractor plays a vital role in quality control for asphalt mixes used in road construction projects across India. This ensures that the pavement materials meet specified standards, contributing to the construction of durable and high-performing roads.