Vacuum Tube, Rubber

Quick Answer: The Vacuum Tube, Rubber is heavy-walled rubber vacuum tubing: a flexible tube whose wall is thick relative to its bore, so that it does not flatten when the air inside is pumped out; it connects filter pumps and vacuum pumps to filtering flasks, desiccators and traps.

Why Vacuum Tubing Has a Thick Wall

Ordinary soft tubing works well under a slight positive pressure, as in a water line, but under suction the outside atmosphere presses on it with nothing inside to push back, and a thin wall simply collapses. Vacuum tubing avoids this by making the wall several times thicker than usual for its bore, so it keeps its round section even when a water aspirator or pump draws a strong vacuum.

The standard school use is vacuum filtration: a Filter Pump on the tap is connected by thick tubing to the side arm of a Filtering Flask carrying a Buchner funnel. The same tubing links vacuum desiccators, vacuum distillation set-ups and cold traps to their pumps, and connects bench suction points to manifold lines in college labs.

The thick wall makes this tube stiffer to push onto glass, so wet the glass barb with water or a little glycerol and ease the tube on with a twisting motion, protecting the hand with a cloth. The bore, wall thickness and rubber type of this listing should be matched to the side arm or pump fitting.

Applications

• Buchner filtration in school and college chemistry practicals.
• Evacuating vacuum desiccators for drying samples.
• Connecting cold traps and manifolds on vacuum pump lines.
• Vacuum distillation connections where the rubber suits the vapours involved.

Specifications

Care & Handling

• Fit a trap bottle between the flask and the pump so liquid cannot be drawn back into the pump.
• Release the vacuum at the flask before turning off a water filter pump, to stop tap water sucking back.
• Inspect the ends for cracks and hardening, and cut off damaged sections.
• Keep the tubing away from solvents, oils and sunlight, which make natural rubber swell or perish.

Why Choose LabEquip

Chemistry departments, pharmacy colleges and research labs buy rubber vacuum tubing as a routine consumable for their filtration benches. LabEquip lists it under General Lab Products; give the side-arm diameter through the contact page to choose the right bore.

Frequently Asked Questions

What is the difference between vacuum tubing and ordinary rubber tubing?

Vacuum tubing has a much thicker wall for its bore, so it keeps its shape under suction. Ordinary soft tubing of the same bore flattens and blocks the line.

How do I fit thick vacuum tubing onto a glass side arm?

Wet the glass with water or a little glycerol, protect your hand with a cloth, and ease the tubing on with a gentle twist. Never force it, because a snapped side arm can cause deep cuts.

Can it be used with organic solvents?

Natural rubber swells in many organic solvents and oils. For solvent vapours, use a cold trap to condense them before they reach the tubing, or choose a more resistant elastomer for that line.

Why does my filtration stop pulling after a while?

Common causes are a collapsed or cracked tube, a poorly seated funnel adapter, or a filter paper that has clogged. Check the tubing ends for splits first.

Should I use a trap between the flask and the pump?

Yes. A trap bottle catches any liquid drawn over from the flask and prevents tap water sucking back into the filtrate when a water filter pump is used.

How long does rubber vacuum tubing last?

It depends on use, but ozone, light, heat and chemicals gradually harden and crack natural rubber. Replace tubing that has become stiff, sticky or cracked.

Last Updated: September 2026