Reed Switch Glass Tubing

Reed Switch Glass Tubing is precision-cut glass specially made for hermetic encapsulation of reed switches. Outer diameters range from approximately 1 mm to over 5 mm, with custom dimensions available. Its high iron content creates a green or blue-green tint, offering strong infrared absorption and favourable ultraviolet transmittance. The tubing hermetically seals reed contacts under inert gas, isolating contacts from atmospheric contaminants to minimise oxidation and carbonisation during switching and extend service life. The reed elements inside deliver fast switching performance, operating 5 to 10 times quicker than conventional electromagnetic relays.

feature application available size Chemical Properties Physical Properties

Feature

This glass material is compatible with both laser sealing and flame sealing processes for reed switch assembly. The glass is fully lead-free and meets the specification requirements for use across a wide range of application sectors.

Application

Reed relays assembled with this reed switch glass tubing are widely deployed across numerous end markets. Typical fields include test and measurement, marine and offshore equipment, meteorological instruments such as pressure gauges and anemometers, construction safety and metering equipment including elevator and lift floor detection systems, test hardware such as matrix modules, RF equipment and modems, automotive electronics and household appliances. The growing prevalence of smart toys and power tools continues to expand the practical scope for reed switches; relevant use cases include rotation, position and temperature sensing for robotic systems, as well as position detection for dolls and consumer toys.

Available Size

Item No.	Outer Diameter (mm)	Wall Thickness (mm)	Acceptable Wall Thickness Range (mm)	Length (mm)	Maximum Straightness
1	1.702 ± 0.03	0.25 ± 0.03	0.22 ~ 0.28	11.1 ± 0.2	1.5‰
2	2.05 ± 0.03	0.28 ± 0.03	0.25 ~ 0.31	15.2 ± 0.2	1.5‰
3	2.45 ± 0.03	0.33 ± 0.03	0.30 ~ 0.36	21.4 ± 0.2	1.5‰
4	2.95 ± 0.05	0.40 ± 0.03	0.37 ~ 0.43	22.3 ± 0.2	1.5‰
5	3.55 ± 0.05	0.45 ± 0.03	0.42 ~ 0.48	29.4 ± 0.2	1.5‰
6	3.95 ± 0.05	0.57 ± 0.03	0.54 ~ 0.60	39.2 ± 0.2	1.5‰
7	4.95 ± 0.05	0.67 ± 0.03	0.64 ~ 0.70	52.8 ± 0.2	1.5‰

*For reference only
OEM is acceptable

Chemical Properties

Property	Rating / Value	Standard Reference
Chemical Stability	25×10⁻⁴	—
Hydrolytic Resistance	Class 3	DIN 12111
Acid Resistance	Class 1	DIN 12116
Alkali Resistance	Class 2	DIN 52322

*For reference only

OEM is acceptable

Physical Properties

Property	Value
Matching Sealing Alloy	NiFe 52
Strain Point	440 °C
Annealing Point	650 °C
Working Point	990 °C
Density	2.56 g/cm³
Modulus of Elasticity	72 GPa
Refractive Index	1.516
Strain Point tk100 (DIN 52326)	250 °C
Volume Resistivity @ 250°C	8.1 Ω·cm
Dielectric Constant (25°C, 1 MHz)	6.4
Loss Tangent (25°C, 1 MHz)	6.5