Thermal trip stop valve
An intermediate bulk container (IBC) for offloading materials comprises a portable tank including a bottom wall having a bottom discharge outlet. A thermal trip stop valve is mounted at the discharge outlet. The thermal trip stop valve comprises a spring loaded emergency valve biased to a closed position and including a lever arm actuable to operate the valve to an open position. A fusible link operatively connects a pull handle to the lever arm so the pull handle manually operates the emergency valve. A latch mechanism latches the pull handle with the emergency valve in the open position, whereby the fusible link opens under high temperature conditions to disconnect the pull handle from the lever arm to close the emergency valve.
1 . A thermal trip stop valve comprising:
a spring loaded emergency valve biased to a closed position and including a lever arm actuable to operate the valve to an open position;
a pull handle;
a fusible link operatively connecting the pull handle to the lever arm so the pull handle manually operates the emergency valve; and
a latch mechanism for latching the pull handle with the emergency valve in the open position, whereby the fusible link opens under high temperature conditions to disconnect the pull handle from the lever arm to close the emergency valve.
2 . The thermal trip stop valve of claim 1 wherein the latch mechanism comprises a plate on the emergency valve having a slot opening and the pull handle comprises a rod extending through the slot opening and having a projection for selectively engaging the plate.
3 . The thermal trip stop valve of claim 2 wherein the slot opening comprises a keyhole slot opening.
4 . The thermal trip stop valve of claim 1 wherein the emergency valve comprises a flange having an extension plate with a keyhole slot and the latch mechanism comprises an arcuate ring on the pull handle for selectively engaging the plate.
5 . The thermal trip stop valve of claim 1 wherein the fusible link opens at a temperature of about 250° F.
6 . An apparatus comprising a bottom wall having a discharge outlet, and a thermal trip stop valve mounted at the discharge outlet including a spring loaded emergency valve, the emergency valve biased to a closed position and including a lever arm actuable to operate the valve to an open position, a pull handle, a fusible link operatively connecting the pull handle to the lever arm so the pull handle manually operates the emergency valve; and a latch mechanism for latching the pull handle with the emergency valve in the open position, whereby the fusible link opens under high temperature conditions to disconnect the pull handle from the lever arm to close the emergency valve.
7 . The apparatus of claim 6 wherein the latch mechanism comprises a plate on the emergency valve having a slot opening and the pull handle comprises a rod extending through the slot opening and having a projection for selectively engaging the plate.
8 . The apparatus of claim 7 wherein the slot opening comprises a keyhole slot opening.
9 . The apparatus of claim 6 wherein the emergency valve comprises a flange having an extension plate with a keyhole slot and the latch mechanism comprises an arcuate ring on the pull handle for selectively engaging the plate.
10 . The apparatus of claim 6 wherein the fusible link opens at a temperature of about 250° F.
11 . The apparatus of claim 6 further comprising a ball valve connected to the emergency valve.
12 . An intermediate bulk container (IBC) for offloading materials comprising:
a portable tank including a bottom wall having a bottom discharge outlet; and
a thermal trip stop valve mounted to the portable tank discharge outlet including
a spring loaded emergency valve biased to a closed position and including a lever arm actuable to operate the valve to an open position;
a pull handle;
a fusible link operatively connecting the pull handle to the lever arm so the pull handle manually operates the emergency valve; and
a latch mechanism for latching the pull handle with the emergency valve in the open position, whereby the fusible link opens under high temperature conditions to disconnect the pull handle from the lever arm to close the emergency valve.
13 . The IBC of claim 12 wherein the latch mechanism comprises a plate on the emergency valve having a slot opening and the pull handle comprises a rod extending through the slot opening and having a projection for selectively engaging the plate.
14 . The IBC of claim 13 wherein the slot opening comprises a keyhole slot opening.
15 . The IBC of claim 12 wherein the emergency valve comprises a flange having an extension plate with a keyhole slot and the latch mechanism comprises an arcuate ring on the pull handle for selectively engaging the plate.
16 . The IBC of claim 12 wherein the fusible link opens at a temperature of about 250° F.
17 . The IBC of claim 12 further comprising a ball valve connected to the emergency valve.
18 . The IBC of claim 12 wherein the bottom wall is sloped toward the discharge outlet.
19 . The IBC of claim 12 wherein the portable tank comprises a steel tank.
20 . The IBC of claim 12 wherein the portable tank comprises a tank having a capacity in the range of about 120 to 793 gallons.