A high power, High frequency Mirowave tube processing station

A high power, High frequency Mirowave tube processing station

High frequency (approx.1000GHz), high power (hundreds of MW) microwavetube has immense importance to the communication guide technology. Microwave tube generates or amplifies microwave radio frequencies.

Most of these tubes are very expensive and are of strategic importance. And hence, a dozen of R&D centers in India are actively involved in developing microwave tubes to make India self reliant and off import.

Manufacturing of microwave tubes has stringent processes as it is to maintain a high vacuum of the order of 1x 10^-9 mbar in an operating vacuum tube.

HHV has been offering various sizes of high vacuum processing station to evacuate, testing different sizes of microwave tubes for degassing of its components at high temperatures and sealing it for ultimate applications to make India self reliant.

The Microwave tube procession station in discussion has been commissioned at Central Electronics Engineering Research Institute (CEERI), Pilani. It is one of the pioneering research institutes in development of microwave tubes.

The microwave tube processing station as shown in the photo has a large size vacuum chamber size of 2700mm ID x 6000mm (Ht.) to process 2000mm(D) x 5000mm (Ht.) length microwave tubes.

It has been made into two halves and a dish-end at the top. The top chamber 2700 mm (ID) x 2700mm height and the bottom 2600 mm (ID) x 2700mm height. A motorized mechanism attached to the structures facilitates to lift the top and bottom chambers. This facilitates to process various sizes of microwave tubes.

It has been designed to control the operating temperature of 650 deg C with a heating rate of 8^°C/min. to 11^°C/min, as the microwave tube should be evacuated at an elevated temperature and then “baked out” to remove trapped gases in the metals components.

A suitably designed turbo based vacuum system facilitates to test the final assembly of microwave tubes, completing the vacuum envelope around the sub-assemblies, at a vacuum of 1.0 x 10^-9 m.bar inside the vacuum tube of 2.0 m³ volume after heating and soaking for required time in fully degassed conditions.

A PC based programmable logic controller has been provided for automation of the vacuum pumping system and to achieve various safety interlocks.