Woulf Bottle

Quick Answer: A Woulf Bottle is a multi-necked borosilicate glass vessel used in the laboratory as a safety trap between a vacuum source and the apparatus being evacuated, and for gas washing or bubbling gas through a liquid. The extra necks allow separate tubes for gas inlet, gas outlet, and liquid access.

Description

The Woulf Bottle from LabEquip is blown from borosilicate 3.3 glass and features two or three necks fitted with interchangeable ground-glass joints. This multi-neck design lets the user pass separate glass or PTFE tubes through the bottle at the same time — commonly one tube reaching below the liquid surface for gas delivery and another remaining above the liquid for gas exit or pressure release.

Woulf bottles are most often used as a safety or “trap” bottle placed in-line on a vacuum filtration or vacuum distillation set-up, where they catch any liquid that might otherwise be drawn back into the vacuum pump, protecting both the pump and the experiment. They are equally suited to gas washing and gas absorption work, where a gas stream is bubbled through a liquid reagent held in the bottle.

Because the body is thick-walled borosilicate glass, the bottle can safely be used under reduced pressure (vacuum) as part of a trap train, and it resists thermal shock and attack from common laboratory chemicals. These bottles are supplied in a range of standard laboratory capacities — confirm the exact volume and neck configuration required for your set-up at the time of enquiry.

Specifications

Applications

• In-line safety trap between a vacuum pump and filtration or distillation apparatus
• Gas washing and purification, bubbling a gas stream through a liquid reagent
• Gas absorption experiments in chemistry teaching laboratories
• General multi-tube liquid handling where separate inlet and outlet paths are needed
• Protecting vacuum lines and pumps from liquid carry-over during evacuation

Care & Handling

• Inspect the ground-glass joints for chips or cracks before each use under vacuum, since a damaged joint can compromise the seal.
• Apply a light film of an appropriate lubricant to ground joints if they are used regularly under vacuum, to maintain an airtight seal and prevent sticking.
• Clean thoroughly with a suitable laboratory detergent and rinse well, ensuring all necks and tubes are free of residue.
• Never exceed the safe vacuum rating of the glassware or use a bottle with visible star-cracks or chips under vacuum.
• Store upright in a dry cabinet with the neck openings protected from dust and impact.

Why Choose LabEquip

LabEquip supplies Woulf bottles and other specialist lab glassware alongside a wider range of chemistry lab equipment for schools, colleges, and industrial laboratories. Our team can help you confirm the right neck configuration and capacity for your vacuum or gas-handling set-up. For bulk orders, institutional procurement, or technical questions about this product, please contact us and our team will assist promptly.

Frequently Asked Questions

What is a Woulf bottle used for?

A Woulf bottle is typically used as a safety trap on a vacuum line, to catch liquid before it reaches the pump, and for gas washing, where a gas stream is bubbled through a liquid held in the bottle.

Why does a Woulf bottle have more than one neck?

The extra necks allow separate tubes to pass into the bottle at the same time, so one tube can carry gas or liquid in while another provides an outlet or connects to the vacuum line, without the tubes interfering with each other.

Can a Woulf bottle be used under vacuum?

Yes, Woulf bottles are commonly used under reduced pressure as part of a vacuum filtration or distillation set-up, provided the glassware is inspected beforehand and is free of chips, cracks, or star-fractures.

What material is the Woulf bottle made from?

It is made from borosilicate 3.3 glass, which offers good chemical resistance and resistance to thermal shock, both of which are important for reliable use in vacuum and gas-handling applications.

What capacity does the Woulf bottle come in?

These bottles are supplied in a range of standard laboratory capacities and neck configurations. Please confirm the exact volume and number of necks you need when you enquire, and our team will help you select the right option.

How should a Woulf bottle be maintained?

Keep the ground-glass joints clean and lightly lubricated if used often under vacuum, clean the bottle thoroughly after use, inspect regularly for damage, and store it upright in a dry cabinet away from impact.

Last Updated: September 2026