Our online catalog is being updated! Please contact us for current pricing. Bakeable Angle & Inline UHV Valves Features All stainless steel construction Entire valve bakeable to 450°C Bakeable in open or closed positions High conductance Replaceable metal alloy gasket Leak tight to less than 2 x 10-11 Torr Right angle or tee styles Operation In the TLI bakeable valve, the seal is formed by impressing a replaceable copper alloy gasket on a stainless steel seat. Re-peatable, reliable seals are easily accomplished under the most adverse vacuum conditions. Thermionics offers three types of UHV Bakeable valves: Angle (BVV) Angle (AMV) Straight Through (SMV) Applications TLI's bakeable valves are for use in ultra-high vacuum systems that are baked up to 450°C. The straightforward design gives maximum reliability and vacuum sealing to pressures below 10-11 Torr.      Since these valves can be baked in either the open or closed position, they can be used for any high temperature vacuum application. Specifications High Temperature The entire valve can be repeatedly baked to 450°C, in either the open or closed position. Mounting Requirements The valve may be mounted and operated in any position. TLI bakeable valves with flanges are supplied with rotatable flanges to simplify mounting. Operating Pressures TLI bakeable valves used in typical all metal or glass/metal UHV systems are reliable to pressures of 10-12 Torr. Vacuum Materials The valve is made of 300 series stainless steel. The seat gasket is a special copper alloy. Only 300 series stainless steel and OFE copper are exposed to the vacuum system. Bellows Sealed Drive The entire valve drive mechanism is isolated from the vacuum system by a welded nesting stainless steel bellows. No sliding vacuum seals are used. Gasket Life The life of the sealing gasket is dependent on the temperature history and the cleanliness of the sealing surface. The sealing gasket should remain reliable through forty 450°C cycles. If the system is not repeatedly baked or only baked mildly, many hundreds of cycles can be expected. Bakeable Valve Mounting Bracket Use of a mounting bracket is recommended in installations where the connecting tubulation will not support the sealing torque load. The bracket can be bolted to any flange of the valve. It can be used as a wrench fixture or can, in turn, be bolted to a rigid member for support. Each of these stainless steel brackets is shipped with the required number of special length bolts for the flange to bracket connection. High Conductance The TLI design allows the full retraction of the sealing gasket and the bellows assembly. Seat constriction is held to a minimum, giving maximum conductance. Gasket Replacement Gasket replacement is simple. No special tools are required. On some systems a tee style valve is used with one port blanked off. This port is used to change the seat without removing the valve from the system. Drive Lubrication After high temperature bakeout, the threads of the drive mechanism must be lubricated to prevent galling and insure proper torque on the seat. The TLI valve drive is sealed from the vacuum system by the stainless steel bellows, and the valve does not have to be removed from the system to be lubricated. Connections All TLI bakeable valves are available with flanges of your choice. Leak Tightness Before shipment, each valve is tested on a helium leak checker to insure leak tightness to 2 x 10-10 std cc/sec.