Figure 5-9.- Operating instructions for TMU-70/ M.

Table 5-1.- Periodic Inspection

the trailer on a level surface or ensure that the tank has a level attitude. Close all control valves on the storage tank. Pressurize the LOX supply tank to the required pressure for transfer to the TMU 70/ M. Remove the dust cover from the supply tank transfer line and purge hose. After purging, connect the fill-drain line coupling (1) (fig. 5-8) to the transfer hose. Open the TMU 70/ M's storage tank vent line shutoff valve (5) and fill-drain line shutoff valve (3).

CAUTION Pressure should not be allowed to rise above 55 psi in the storage tank. Monitor the storage tank pressure gauge (7) closely during cooldown.

Open the service valve on the supply tank slowly, and allow only a partial flow of LOX through the transfer hose and into the trailer. Considerable vaporization will take place until the transfer hose, fill-drain line, and storage tank on the trailer have cooled down. When these have sufficiently cooled and are able to handle a full flow of LOX, open the service valve on the supply tank completely. During filling, LOX flow is through the fill-drain line filter (2) and shutoff valve (3) to the storage tank. The relief valve (4) is provided to prevent excessive pressure if the fill-drain line shutoff valve and the service valve on the supply tank are closed with cold gas or liquid trapped within the supply line. The relief valve (4) is connected to the vent line for safe discharge overboard. The vent line shutoff valve (5) is opened during filling and normal storage where safe overboard discharge is provide. Storage tank conditions are monitored and indicated by the liquid level gauge (6) and pressure gauge (7). The inner shell relief valve (8) and rupture disc (9) are provided in case of excessive pressure in the storage tank. Monitor the storage tank liquid level gauge (6) during filling. When it indicates 50 gallons or LOX starts to flow out the vent manifold, close the service valve on the supply tank. Close the fill-drain line shutoff valve (3) to relieve internal pressure.

CAUTION Use extreme caution when disconnecting the transfer hose. Even though the hose has been drained and the pressure relieved, some LOX will still remain. Do not direct the hose toward personnel or other equipment.

Disconnect the supply tank transfer hose, immediately drain the LOX that remains, and replace the coupling cap loosely. Tighten the cap after ensuring that all LOX has vaporized and bled off. Close all control valves on the service trailer except the storage tank vent valve (5).

NOTE: Observe the time required to fill the TMU-70/ M. Filling will vary with each supply tank and supply line system. Under normal con-ditions and 30 psi transfer pressure, the storage tank should be filled within a period of 5 to 10 minutes. Abnormal deviation from the average filling time should be cause for investigation.