VACUUM FEEDTHROUGHS

Vacuum Services has the capability to repair and service electrical Vacuum feedthroughs to your specification. It is also a cost-effective way to get your equipment back into service.

We also have the facility to machine standard flanges to make a custom combination feedthrough to suit your project or requirements. Our wealth of experience in manufacturing techniques used to produce these items is your guarantee of unbeatable quality, and our many years of experience in the vacuum technology ensures the high quality needed for UHV applications. All of our Vacuum feedthroughs are TIG welded, the whole assembly is helium leak checked and issued with a certificate of conformity if requested.

Feedthroughs are hermetic, vacuum sealed components and assemblies that have a conductor (wire, pins or solid rod) mounted into a ceramic to metal, glass to ceramic insulator joint to electrically isolate the current carrying conductors from the metallic mounting. They are suitable for high vacuum (HV) and ultra-high vacuum (UHV) environments and temperatures ranging from -270°C to 450°C.

Feedthroughs are used to transport a signal, electrical current, temperature measurement or fibre optic into/from a Vacuum Vessel. Feedthroughs are supplied in weld able or flanged configurations. They are defined by the requirements of the intended use, installation, insulation and conductor material.

• Feedthroughs for low voltages (up to 12 kV)
• Water-cooled feedthroughs and RF feedthroughs
• High-voltage feedthroughs (20 to 100 kV)

ELECTRICL POWER FEEDTHROUGHS

Electrical Power Feedthroughs provide transportation of electrical current into and out of a Vacuum Vessel. Electrical Power Feedthroughs are available in a vast variety of types, mounting flanges, voltages, and current carrying capacities.

Electrical Power Feedthroughs are available from in the Voltage & Current range 1-kV 3 A to 8 kV 500 A

MULTI-PIN FEEDTHROUGHS

Multi-pin Feedthroughs are feedthroughs with two or more conducting pins and are designed to accept a plug on the air side, but some feedthroughs allow for plugs on the vacuum side also.

Hermetically sealed Multi-pin Feedthroughs are designed primarily to provide instrumentation signals, voltage and/or current into/from a High-Vacuum (HV) or Ultra-high Vacuum (UHV) Vacuum Vessel.

• Voltages up to 12 kV DC
• Currents up to 40 A
• Temperature range from -269°C to 450°C
• Internal pressure 1×10-10 mbar up to 41 bar (600 psig)
• Up to 50 pins/conductors

CO-AXIAL FEEDTHROUGH

Co-axial Feedthroughs are connectors that consist of two concentric conductors: a central inner conductor serves as a current carrying contact and is surrounded by and insulated from an outer tubular conductor that serves as an electromagnetic shield. The outside conductor is usually at ground potential but in some product variations may be floated off ground by employing an additional insulating ring. The outer conducting surface can prevent radio frequency noise from passing to or from the central conductor.

The standard coaxial plug options are BNC, MHV, various SHVs, N, Microdot, SMA, and SMB.

Industry Standard Specifications

• Grounded shield or floating shield configuration
• High frequency 50 ? impedance matched connectors as SMA, BNC, Type N and HN
• Connectors are sold with or without air side plugs

INSTRUMENT FEEDTHROUGHS

Instrument Feedthroughs are designed to transfer low current, low or high voltage signals from low or high impedance into/from a Vacuum Vessel. They have one or multiple conductors (wire) with a standard electrical plug/socket on the air-side. Some types also are suitable to have connections on the vacuum side.

THERMOCOUPLE FEEDTHROUGHS

Thermocouple Feedthroughs are used to measure temperature inside a Vacuum Vessel. Thermocouples are manufactured with differing thermocouple materials or compensating material. The differing materials transmit electromotive force (EMF) generated by the heat application to the thermocouple hot junction (bead joint) transmitted from the inside of a Vacuum Vessel. External temperature measurement controllers evaluate the strength of the electromotive force that is proportional to the temperature at the hot junction and displays the temperature.

Typical ANSI-standardized thermocouple material pairs are listed in the table below.

Thermocouple Type	Thermocouple Materials	Polarity	Measurable Temperature Range (°C)
T	Copper Constantan	+ –	-200 to 350
K	hromel® Alumel	+ –	-200 to 1250
R/S	Platinum 13/10 % Rhodium* Platinum	+ _	0 to 1450
J	Iron Constantan	+ _	0 to 750
E	Chromel® Constantan	+ _	-200 to 900
C	Wolfram 5 % Rhenium Wolfram 26 % Rhenium	+ _	0 to 2315

Contact Vacuum Services Ltd. to discuss your requirements.
Tel: 01424 447726
Email: [email protected]