18mm Magnetic Precision Screw Caps & Septa Supplier

Description

Feature

Specification

Application

Product

FAQ

Packing and Delivery

Product Overview

The septa are the heart of your analytical integrity. Our 17.5mm septa utilize high-purity, MS-certified silicone bonded to a chemically resistant PTFE liner without adhesives. This ensures a stable, inert barrier that prevents sample degradation and solvent interaction.

Through a specialized thermal conditioning process, we remove siloxanes that cause "ghost peaks" and baseline noise. Whether you use our standard PTFE/Silicone or our specialized SPME soft-entry septa, you are guaranteed a contamination-free seal for sensitive GC/MS detectors.

Product Features

Precision engineered for flawless autosampler performance.

Robotic Optimized: Strong magnetic properties for reliable transport by CTC PAL systems.

Ultra-Low Bleed: High-grade silicone septa minimize background interference.

Chemical Resistance: PTFE liners provide an inert barrier against aggressive solvents.

Temperature Stability: Maintains seal integrity during high-temp headspace heating.

Pre-assembled Convenience: Caps and septa arrive ready to use, saving lab time.

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ND18 Technical Specs & Ordering

Detailed Ordering & Specs

Septa Technical Performance

System Integration

Part No.	Septa Material	Thickness	Hardness (Shore A)	Features	Pcs/Pack
SACA001	Blue PTFE / White Silicone	1.5mm	45°	Standard bleed, High resealing	100
SACA002-II	Red PTFE / White Silicone	1.3mm	45°	Thinner for easier penetration	100
SACA003-II	White PTFE / Blue Silicone	1.3mm	35° (Soft)	Optimized for SPME Fibers	100
SACA004	Gray PTFE / Red Butyl	1.6mm	55°	High chemical resistance	100
SACA001002	Blue PTFE / White Silicone	1.5mm	45°	Closed-top for storage	100

Septa Material	Temp. Range	Resealing	Chemical Compatibility	Best For
PTFE / Silicone	-60°C to 200°C	Excellent	High purity, Alcohols, Ethers	GC/MS, Trace Analysis
PTFE / Butyl	-40°C to 120°C	Good	Acids, Bases, Low VOCs	Routine GC, Industrial
SPME Silicone	-60°C to 200°C	Superior	Specialized for SPME needle	Solid Phase Microextraction

Autosampler System	Drive Method	Required Feature	Compatibility	Operational Benefit
CTC PAL (RTC, RSI)	Robotic Arm	High Magnetic Flux	100%	Stable pick-up & high-speed move
Agilent (7697A/G1888)	Tray / Carousel	Precision Threading	100%	Prevents carousel jamming
Shimadzu (HS-20/10)	Mechanical Gripper	Precise Outer Dia.	100%	Airtight sampling, no leakages
Gerstel MPS	Multi-Tool	Magnetic Steel	100%	Reliable tool-change transitions

Application

For a wide range of analytical problems, our ND18 magnetic screw system is the best solution. These caps are flexible and dependable enough for current high-throughput labs to use for everything from important pharmaceutical purity tests to complicated environmental VOC monitoring. Find out how our unique septa solutions can make your chromatographic operations operate better for you.

Standard Headspace GC Analysis

Reliable sealing for routine gas chromatography and residual solvent testing.

SPME Specialized Application

Ultra-soft septa (SACA003-II) designed to protect fragile SPME fibers and needles.

Environmental VOC Monitoring

Low-bleed PTFE/Silicone septa ensure high sensitivity for volatile organic compound analysis.

Food & Fragrance Testing

Excellent chemical inertness for capturing delicate aroma profiles without contamination.

Sample Storage (Closed-top)

Closed-top magnetic caps (SACA001002) prevent sample evaporation during long-term storage.

ND18 Technical Advantages

Our ND18 system redefines precision in chromatography. By combining metallurgical excellence with polymer purity, we provide a sealing solution that withstands the rigors of modern high-throughput laboratories.

Improved Magnetic Flux for Robotics

Our caps are made of high-quality magnetic steel with the best flux density, so robotic arms like the CTC PAL RTC/RSI will never drop a vial, even when they are going as fast as they can.

Ultra-Low Bleed & MS-Certified Septa

We use a special conditioning procedure to get rid of low-molecular-weight siloxanes, which cuts down on baseline noise and ghost peaks a lot in sensitive GC/MS and LC/MS applications.

8mm Precision Center Hole

The CNC-machined center hole makes sure that everything is perfectly lined up. This cuts down on "coring" (when pieces of the septum fall into the vial) and makes your expensive autosampler needles last longer.

Uniform Thread Geometry

Our metal screw caps fit snugly around the vial rim without deforming, unlike plastic caps. This keeps "cold flow" leaks from happening during overnight heating cycles.

Multi-Layer Septa Bonding

The PTFE liner is molecularly bonded to the silicone/butyl base without the use of adhesives, eliminating a common source of chemical contamination in trace analysis.

Oct

Packing and Delivery

Packing

Each vial is individually protected in shrink-wrapped trays, 100–200 pcs per inner box, then packed into corrugated export cartons.

Labeling

Each carton includes lot number and product information for traceability.

Delivery Time

Normally 7–15 working days after order confirmation.

Shipping Options

Air freight, sea freight, or express (DHL/UPS/FedEx) available upon request.

Storage Condition

Store in a clean, dry environment at room temperature.

Company Profile

Zhejiang Aijiren Technology Co., Ltd.

A dedicated original manufacturer of chromatography and laboratory consumables.

10,000+ m² modern facility with Class 100,000 cleanrooms
Automated production lines and rigorous in-house quality control
High-volume capacity, fast lead times, and reliable global supply
OEM/ODM customization with full batch traceability
Trusted by laboratories and analytical instrument brands worldwide

VR Showroom

OEM/ODM Custom Laboratory Consumables

Aijiren turns your customized requirements—size, material, color, logo, or packaging—into reliable, ready-to-use products.

OEM/ODM

Precise manufacturing based on your drawings and specifications, with one-stop development support

Confidentiality

Full protection of all commercial information, molds, and designs

Stable Supply

Automated production ensures consistent quality and fast lead time

Technical Support

Dedicated team ensures smooth communication and hassle-free delivery

FAQ From Customers (VR Display)

What certificates do you have?

Aijiren is certified to ISO 9001:2015 by SGS, ensuring controlled manufacturing processes and stable, fully traceable product quality.

With continuous investment in R&D and multiple independent patents, we deliver high-performance and reliable consumables to laboratories worldwide.

Some of the certificates of Aijiren are displayed

What’s the MOQ? Do you accept small orders?

Aijiren supports both standard and small batch orders. While MOQ varies by product type, we are happy to accommodate smaller quantities for trial, testing, or special projects. Please contact us for specific requirements. aijiren Quality control

Is the quality guaranteed?

All Aijiren products undergo random sampling and multiple in-house quality tests. Each batch is fully traceable, ensuring stable and reliable performance for your laboratory work.

What kind of after-sales support does Aijiren provide?

Aijiren provides practical after-sales support:

● Returns & replacements: Any product affecting use or sales can be returned or replaced.

● Technical support: Assistance with product use and troubleshooting.

● Order tracking & follow-up: We monitor shipments and follow up to ensure timely delivery.

● Dedicated contact: Aijiren provides a direct contact for after-sales inquiries.

This ensures your laboratory work runs smoothly with minimal disruption.

How long will it take for orders?

The delivery time depends on the order quantity and whether customization is required:

In-stock products: shipped within 3–7 days after payment
Standard bulk orders: shipped within 2–4 weeks
OEM/ODM customized products: shipped within 3–5 weeks (depending on mold, logo, color, packaging, etc.)
Aijiren has automated production lines and a 100,000-class cleanroom, ensuring stable lead times and reliable supply.