20mm Aluminum Crimp Caps & Septa Supplier

The Gold Standard for Secure Headspace Sealing

The 20mm crimp-top system is the best in the business for volatile analysis and provides the best sealing for Headspace GC. Our aluminium caps make sure that the seal is even all the way around, so that samples don't get lost during high-temperature incubation. They fit perfectly with the vial rim.

Specialised Magnetic and Safety Options: Our magnetic caps make sure that robotic systems like CTC PAL can be moved safely. Our Pressure Release Caps work like safety valves. They open at 3.0 ± 0.5 bar to keep vials from breaking when they get too hot.

Advanced Engineering for Robotic & Manual Systems

Engineered for chemical resistance and robotic precision.

Robotic Optimized: Magnetic versions ensure zero-drop transport in CTC PAL and Gerstel systems.

Ultra-Pure Septa: Thermal conditioning removes siloxanes, ensuring clean baselines in GC/MS.

Pressure Safety: Pressure-release bridges prevent accidental vial explosions during over-heating.

Chemical Inertness: High-grade PTFE liners provide a robust barrier against aggressive solvents.

Karl Fischer Fit: Specialized 10mm hole caps designed for seamless needle entry in KF titrators.

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Technical Support & Selection

Septa Selection & Chemical Resistance

Cap Type & Autosampler Compatibility

Application Troubleshooting

Septa Material	Temp Range	Shore A Hardness	Chemical Compatibility	Recommended For
PTFE / Silicone	-60°C to 200°C	45° - 50°	High resistance to most acids and alcohols	Routine GC Headspace / VOCs
Pharma-Fix (PTFE/Sil)	-60°C to 200°C	50° - 55°	Best for trace analysis, lowest bleed	High-Sensitivity GC/MS Analysis
PTFE / Butyl	-40°C to 120°C	55°	Excellent gas barrier, prevents evaporation	Long-term Sample Storage / Pharma
Moulded Butyl	-40°C to 120°C	60°	High seal integrity, budget-friendly	General Gas Sampling / Low Pressure

Cap Type	Material	Center Hole	Robotic Pickup	Compatible Instruments
Standard Aluminum	High-Grade Alum.	9.5mm	No (Manual)	Agilent 7694, Waters Headspace
Magnetic (Blue/Red)	Steel Insert	8.0mm	Yes (High Flux)	CTC PAL, Gerstel, Shimadzu AOC
Pressure Release	Alum. w/ Bridge	9.5mm	No (Manual)	High-Pressure/High-Temp Incubation
Karl Fischer Spec.	High-Grade Alum.	10.0mm	No (Manual)	Metrohm, Mettler Toledo (KF Vials)

Lab Problem (Pain Point)	Root Cause	Recommended Solution	Technical Advantage
"Ghost Peaks" in MS	Septa siloxane bleed	Switch to Ultra-Low Bleed Septa	Vacuum-baked conditioning removed siloxanes
Vial Bursting @ High Temp	Internal pressure > 5 bar	Use Pressure Release Caps	Caps open at 3.0±0.5 bar for safety
Needle Bending/Coring	Hole size too small	Use 10mm Center Hole Caps	Easier needle entry, reduces coring
Sample Loss/Evaporation	Poor crimp seal	Check Cap Ductility	Our Alum. alloy ensures 360° uniform seal
Robot Drop Events	Low magnetic flux	Use High-Carbon Magnetic Caps	Stronger attraction for robotic magnets