Australian Pipeline Valve - Installation, Operation and Maintenance Manual 16 API6D THROUGH CONDUIT EXPANDING GATE VALVE - AP400-405 SERIES 8.2.2 Seat Lubrication/Sealant a- Twin secondary sealant injection ports are fitted in the middle of the valve body. In the case of seat sealing surface damage or leakage, a grease gun can be used with an approved sealant to inject the seats. b- The pressure required to fully inject sealant into the seat/gate surfaces should not exceed 3000 psi over the line pressure. There will be some pressure needed to pump the grease through the gun, hose and extended piping. The amount could be several pounds of pressure more in colder weather. Please note the following example: Pressure to pump grease: 13,780 kPa Line pressure: 6,890 kPa Amount required above: 2,067 kPa Total amount in cold weather: 22,048 kPa c- Lubricating the seats on a through conduit gate valve is not necessary however, this will ensure smooth operation. When lubricating the seats and gate surfaces, cycle the gate OPEN and CLOSED several times to evenly lubricant both surfaces. d- Return the gate to either the full OPEN or full CLOSED position and inject an additional amount of lubricant to complete the process. e- APV recommends for buried valves, a minimum of 4 cups of lubricant per valve once extended lines are filled. f- While APV does not generally recommend a lubricant, we do recommend containing Climax Valve Lubricants with the specifics of the product in the line for a lubricant best suited for the intended service. Figure 1: Secondary Seat Lubricant/Sealant Injection System