The Everlasting Double-Disc Coke-Oven Valve (METC SOA Test Valve No. A-8) accumulated 628 cycles in the Valve Static Test Unit and 8893 cycles in the Valve Dynamic Test Unit. The test valve performed satisfactorily during the ambient and 300/sup 0/F operating temperature static tests. Some design modifications were required to successfully complete the tests at 600/sup 0/F temperature. During dynamic testing, the valve leakage rates and wear rates were within acceptable limits after 8500 cycles using limestone as the test medium. However, when the medium was changed to aluminum oxide, the valve suffered severe damage by abrasive scoring of all the seating surfaces. Further testing was cancelled. The overall test data for the test valve show favorable results. The valve offers a solid basic design from which a successful multi-purpose lockhopper valve could be developed. It offers ease of fabrication and maintenance, and with some modifications, could be a very promising valve choice for lockhopper applications.