Softening Point Ring and Ball Apparatus Assembly

Softening Point Ring and Ball Apparatus Assembly

The Softening Point Ring & Ball Apparatus Assembly, also known as the ball method apparatus, is used to determine the softening point of asphalt, coal tar pitch and other viscoelastic bitumens in the range 30°-157°C (86°-315°F).

Steel balls are placed on top of bitumen specimen disks in test rings in a bath. The temperature of the bath is increased until the specimens soften and fall under the ball weight to the shelf 1in (25.4mm) below. The Softening Point Apparatus allows for testing of two specimens at the same time as per standard test procedures. The Apparatus includes two square-shouldered brass test rings, two 3/8in (9.5mm) steel balls, two brass ball-centering guide rings, an 800ml heat-resistant beaker (bath), and a brass ring holder suspension assembly with cover and shelf to fit beaker as per specs. If not already in the lab, a Tirrill Burner, ASTM Softening Point Thermometers and a Beaker Stand Assembly should also be purchased.

Meets Test Methods: AASHTO T53, ASTM D 36, ASTM C143

Overview

The Ball and Ring Apparatus is a laboratory device used for the softening point of various materials, asphalts, pitches, tars and most resins. This apparatus is used to demonstrate thermal expansion and to determine the temperature at which a solid substance starts to soften and lose its shape under specific conditions. The setup includes a brass ball and a brass ring, each on a handle, used for temperature testing and measurement. The Ball and Ring Apparatus is known for its reliability and accuracy, a must have for temperature testing.

When the ball is heated, what do you think will happen? Will the ball still fit through the ring, or will some physical change happen due to thermal expansion?

Components and Setup

The Ball and Ring Apparatus consists of:

• Brass Ball and Brass Ring: On a wooden handle, these are the parts used for the softening point.

• Cover and Thermometer Port: For temperature measurement and to keep the test environment intact.

• Double Set Up Fixture: For control to get consistent results.

• Stirrer: For uniform heating of the sample.

• Steel Balls: For repeated testing.

• Ring Holder: Holds the ring during testing.

• Hot Plate: For heating the sample.

To assemble the apparatus place the brass ball and ring on the handle, attach the cover and thermometer port and use the double set up fixture for control. The stirrer will help in heating the sample uniformly for accurate results.

Maintenance and Calibration

Maintain the Ball and Ring Apparatus regularly for accurate and reliable results. Follow these:

1. Cleaning and Drying: Clean and dry the apparatus after each use to avoid contamination and extend life.

2. Calibrate Thermometer Port: Calibrate the thermometer port regularly for accurate measurement.

3. Check Magnetic Stirrer: Make sure the stirrer is working properly for uniform heating.

4. Replace Balls: Replace steel balls regularly for accurate testing.

Follow these maintenance and calibration steps to keep the Ball and Ring Apparatus in good condition.

Applications and Industries

The Ball and Ring Apparatus is used in many industries because of its flexibility and accuracy:

• Construction: The point of asphalts and pitches to ensure material quality and performance.

• Manufacturing: To determine the point of resins and other materials for quality control.

• Physical Science: To demonstrate thermal expansion and to measure the softening point of various materials for scientific research and education.

• Education: A must have for teaching students about thermal expansion and softening point of materials, hands on learning.

Safety Precautions

When using the Ball and Ring Apparatus follow these safety precautions:

• Handle with Care: Don’t break.

• Wear Protective Gear: Wear gloves and eyewear to protect yourself from hazards.

• Proper Calibration and Maintenance: Make sure it is calibrated and maintained properly to get accurate results.

• Well Ventilated Area: Use in a well ventilated area to avoid heat and chemicals.

• Read Manual: Follow the manual for use and maintenance.

Use the Ball and Ring Apparatus safely.

Components and Assembly

Some versions of the apparatus may have balls for alternative demonstrations, but brass ball is preferred as it has more pronounced thermal expansion properties. The design, including the wooden handle and precise mounting ensures it is safe and effective for demonstrating the effect of heat on metals.

Calibration and Operation

To demonstrate thermal expansion with the ball and ring apparatus, the brass ball is first tested to see if it fits through the ring. The ball is then heated, usually over a flame, and it expands. As it increases, the ball’s diameter grows until it no longer fits through the ring, a clear measurable example of thermal expansion. For more advanced applications like determining of materials like bitumen or wax, a modified version known as Ring and Ball Apparatus is used. In this setup, the ball is gradually heated is until the ball passes through a softened sample, the material’s point. This is standardized to get consistent and reliable results, making the ball and ring apparatus a trusted tool in educational demonstrations and material testing laboratories.