ISO Nipples
ISO-K Nipples
ISO vacuum nipples extend straight length within a vacuum line where two ISO-K flanges connect, such as between a chamber port and a valve, or where components like gauges, pumps, and feedthroughs require clearance from surrounding hardware. Featuring an ISO-K flange on both ends, each nipple clamps into place without welding and can be easily disassembled for system maintenance. Standard construction utilizes 304L stainless steel flanges, rated to 1×10⁻⁸ Torr and bakeable up to 200°C.
ISO-K and ISO-F Half Nipples
A half nipple has a flange on one end and plain tubing on the other. The tube end edge is prepared for a butt weld, which is the standard way to add an ISO port to a custom chamber, manifold, or instrument. The tube end can also be sealed with a quick-connect fitting instead of welding it.
ISO-K Reducer Nipples
ISO reducer nipples connect two different LF flange sizes within a single component—such as adapting an ISO 160 chamber port to an ISO 100 valve—eliminating the need to combine separate adapters and nipples. Selecting between conical reducer nipples
and straight reducer profiles depends on conductance requirements and available spatial clearance.
For ISO-to-KF size changes, see our hybrid adapters. For full KF layouts, see KF Nipples.
Complete the ISO Connection
Each ISO-K flange seals using a centering ring with an O-ring and is secured via claw clamps, whereas ISO-F (LFB) flanges are sealed using standard bolt assemblies. Compatible claw clamps and bolt rings can be sourced through ISO Clamps & Fasteners, and centering rings with O-rings are available in ISO Hardware & Seals. To complete your system layout, explore our selection of ISO Flanges, ISO Tees, ISO Elbows, ISO Crosses, and ISO Bellows & Flexible Hose for applications requiring flexible alignment.
Frequently Asked Questions: ISO Nipples
Yes. The ISO naming convention equates ISO-K with ISO-LF. ANCORP’s reference number structure for ISO-K flanges favors the LF naming. The same equivalence is true for the pairing ISO-F and ISO-LFB.
An ISO nipple has a flange on both ends, so it clamps or bolts into the line without welding. An ISO half nipple has one flange and one butt-weld tube end, for adding an ISO port to a chamber or custom part. Both come in ISO 63 to ISO 500.
Yes. Build a custom length or flange combination in the Nipple Configurator, or request a quote for added ports, 316 stainless or other ISO sizes.
Select a conical reducer for maximum vacuum conductance and optimal flow efficiency. Select a straight reducer for space-constrained assemblies requiring a compact, 2.95-inch body length.