BOILING FLASK GROUND NECK

Description

A Ground Neck Boiling Flask is a specialized laboratory vessel designed for modular assembly. Unlike standard flasks with plain rims, these feature a frosted, precision-ground glass joint at the neck. This allows for an airtight, leak-proof, and grease-free connection with other “Quickfit” or jointed glassware components.

Key Product Features

• Precision Ground Joint: The neck features a standard taper (usually a 1:10 ratio) that is frosted to ensure a perfect seal. Common joint sizes include 14/23, 19/26, 24/29, and 29/32.

• Modular Compatibility: Designed to connect directly to condensers, fractionating columns, separatory funnels, and thermometers without the need for rubber stoppers or corks.

• High-Vacuum Seal: When properly used (sometimes with a thin layer of PTFE sleeves or vacuum grease), these joints can maintain a high-vacuum seal, making them essential for vacuum distillation.

• Borosilicate 3.3 Construction: Offers maximum resistance to thermal shock and chemical corrosion. It can be heated directly over a mantle or flame (with gauze) up to 500°C.

• Available Shapes:

  • Round Bottom (R/B): Ideal for uniform heating and vacuum applications.

  • Flat Bottom (F/B): Convenient for standing on hotplates or benches.

Understanding Joint Sizes

Standard ground joints are identified by two numbers (e.g., 24/29):

1. The First Number (24): Represents the outer diameter (in mm) of the widest part of the joint.

2. The Second Number (29): Represents the length (in mm) of the ground surface.

Note: To ensure a proper fit, the “Male” (Cone) joint of your condenser must match the “Female” (Socket) joint of your boiling flask.

Technical Specifications

Primary Applications

• Distillation: Serving as the “reboiler” where the mixture is heated to create vapor.

• Refluxing: Boiling a solution while continuously condensing the vapors back into the flask to maintain a constant temperature for long reactions.

• Rotary Evaporators: Specifically used as the evaporating flask to remove solvents under reduced pressure.

• Airtight Storage: When used with a ground glass stopper, it provides a superior seal for volatile chemicals.

Maintenance & Safety

• Joint Seizing: Never leave joints connected for long periods after heating, as they can “freeze” or seize. If this happens, gentle heating or a specialized joint gripper may be required.

• Clamping: Always use a joint clip (Keck clip) to secure the connection between the flask and the next piece of glassware to prevent accidental separation.

• Uniform Heating: Use a heating mantle that matches the flask size for the most efficient and safe heat transfer.