PTFE Key Stopcock Straight Bore – High-Precision Fluid Control
The SGC LABS® PTFE Key Stopcock Straight Bore is the ideal choice for modern laboratories seeking reliable, grease-free fluid regulation. Unlike traditional glass plug stopcocks that require frequent greasing and risk contaminating your samples, this stopcock features a self-lubricating Teflon (PTFE) key. The precision-ground housing is manufactured from high-quality Borosilicate Glass 3.3, providing exceptional thermal stability and maximum resistance against aggressive chemicals and acids.

Why PTFE Key Stopcocks? – Design & Performance Advantages
The combination of a borosilicate glass body and a straight-bore PTFE plug is recognized as the laboratory standard for high-purity applications:

Grease-Free Operation: Eliminates sample contamination risks and time-consuming cleaning of frozen joints.
Straight Bore Design: Provides a direct, unobstructed flow path when fully open, ensuring minimal pressure drop and easy clearing.
Chemical Inertness: The PTFE plug resists virtually all common laboratory solvents, acids, and bases.
No Freezing: PTFE expands and contracts smoothly, preventing the plug from getting stuck or “freezing” inside the glass barrel.
Precise Control: Finely threaded retention nut allows you to adjust the turning tension for smooth, incremental fluid adjustment.

Key Features

Material (Body): Borosilicate Glass 3.3 – highly resistant to thermal shock and chemical corrosion
Material (Plug): Pure PTFE (Teflon) – self-lubricating, non-stick, and chemically inert
Bore Type: Straight bore (single channel straight through flow)
Bore Sizes Available: 1.5mm, 2.0mm, 2.5mm, 3.0mm, 4.0mm, 6.0mm
Retention System: Threaded PP screw nut with washer for secure positioning
Temperature Range: Glass body safe up to 500°C; PTFE plug safe up to 250°C
Compliance: Generally conforms to ISO 4785 / DIN 12541 standards

PTFE Key vs Glass Key Stopcocks – Feature Comparison

Feature / Property
PTFE (Teflon) Key Stopcock
Traditional Glass Key Stopcock

Lubrication
100% Grease-Free (Self-lubricating)
Requires silicone or hydrocarbon grease

Contamination Risk
None – Ideal for high-purity chemistry
High – Grease can dissolve into organic solvents

Risk of Freezing/Sticking
Zero – Does not stick or freeze
High – Alkaline solutions can lock the plug permanently

Maintenance
Extremely low, easy to wipe and reassemble
High – Needs constant degreasing and re-greasing

Applications

Burette replacement parts and custom titration assemblies
Separatory funnels and chromatography column flow regulation
Synthesis setups, distillation apparatus, and manifold connections
Academic chemistry labs, industrial R&D, and quality control processes

Why Choose SGC LABS®?
SGC LABS® stopcocks undergo a rigorous grinding process to ensure that the internal taper of the glass barrel matches the PTFE plug flawlessly. This eliminates micro-gaps and guarantees a completely leak-proof performance under standard laboratory pressures. Every assembly is vacuum-tested for seal integrity before leaving our facility in Ambala, India. Trusted by research institutions and educational labs worldwide since 2003.