O-rings for D.O. Sensors
Internal O-rings for 19 mm and 25 mm D.O. Sensors
O-rings need to be replaced over time. Internal o-rings for 19 mm and 25 mm D.O. sensors are included with each membrane kit. However, bulk packs are also available.
Internal O-rings for 12 mm D.O. Sensors
O-rings should be on hand when changing the membrane cartridge of a D.O. sensor. These internal o-rings are included in membrane cartridge kits.
However, membrane cartridge bulk packs do not include o-rings or electrolyte solution.
19 mm External O-rings
This silicone o-ring will fit the external groove of any 19 mm D.O. sensor or housing. It should be replaced regularly to ensure that the housing or sensor fits securely into the port.
Standard 25 mm External O-rings
The external silicone o-ring on a 25 mm D.O. sensor is the same as the one found on a 25 mm housing. It should be replaced regularly to ensure that the sensor fits securely into the port
25 mm B. Braun Biotech External O-rings
The B. Braun Biotech D.O. sensors and housings have an EPDM o-ring seal.
The internal diameter is slightly larger and the cross-section is slightly smaller than the external silicone o-rings found on other Broadley-James 25 mm housings and D.O. sensors.
O-rings for D.O. Sensors and pH Electrodes
The Viton o-ring and Teflon washer found on 12 mm D.O. sensors is the same as those found on FermProbes with metric threads. These seals should last the lifetime of the sensor or electrode, but replacements can be purchased in sets of three.
In order to keep moisture out of the connector during autoclaving, FermProbes have a small o-ring gasket at the base of the connector.
These o-rings should last the lifetime of the electrode. However, they may need to be replaced on occasion due to loss during handling.
O-rings for 25mm Housings
Broadley-James Models 320, 330, 370 housings use the same set of o-rings. O-rings should be inspected regularly and replaced at the first sign of wear.
The external EPDM o-ring on the B. Braun Biotech housings, Models 322, 326 and 336, has a slightly smaller cross-section than those found on other Broadley-James housings.
The internal silicone o-ring is the same on all Broadley-James housings. Regular inspection and replacement is recommended. Do not use grease on any housing o-ring.
Broadley-James also offers a thicker, more pliable o-ring for certain applications. It has a larger o.d. but is more compressible than other silicone o-rings. It can be used on any standard 25 mm housing or D.O. sensor. This unique o-ring was designed to compensate for port imperfections such as a port that is out-of-round or has an i.d. slightly greater than 25 mm.