Minnesota Valley Engineering, Inc.

Mve, Inc.

Duane Preston

Paul A Drube

Thomas Karl Drube

Tom Drube

Michael Lutgen

Keith W Gustafson

Timothy A Neeser

Tom Chrisfield

A snap-action flow interrupt device for terminating flow into a cryogenic storage container utilizes the momentum of the incoming liquid spray as a means of maintaining a float in a submerged position until the proper liquid level is attained. The incoming spray of liquid exerts a downward impact force on a surface of the float. The rising liquid level exerts an upward and increasing buoyant force on the float. When the rising liquid in the tank disrupts the spray, the buoyant force snaps the float upwards to interrupt the flow of liquid. The abrupt motion of the float generates a pressure spike and flow reduction, either of which may be easily detected by automatic fill termination devices or by a human operator.

Float-type shut off device for a cryogenic storage tank

A portable self-contained delivery station for liquid natural gas (LNG) is provided on a movable skid frame and equipped with an instant -on delivery system which may initiate LNG delivery immediately to a use vehicle. The skid is equipped with a spill containment feature such that the LNG may be contained in the event of spillage. A variable speed pump both controls LNG dispensing and saturation levels of the stored LNG. The pump is submerged in a sump tank which is separate from the bulk storage tank. The sump tank is flooded with an amount of LNG such that the pump is submerged. Delivery of LNG may thus occur instantly, without pre-cooling of the pump or associated meter.

Self-contained liquid natural gas filling station

A cryogenic meter is mounted in an insulated container having an inlet and outlet in circuit with the LNG delivery flow path. The container is filled with LNG to a level above the cryogenic meter to pre-cool it to a desired operating temperature. To maintain the level of LNG in the container during use and to separate vapor from liquid, a float device allows vapor to be returned to the storage tank from the container to refill it with LNG. Because the meter is continuously immersed in LNG during use, it is maintained at a constant temperature permitting the quantity of LNG delivered to a use device to be accurately metered. Temperature and/or pressure signals are sent to a microprocessor which computes the density of the LNG and displays the metered amount of LNG on a display.

Metering apparatus for cryogenic liquids

The invention consists of at least one layer of super insulation surrounding the vessel containing the cryogenic liquid. A thin layer of high temperature insulation surrounds the super insulation. Both layers of insulation are surrounded by an outer jacket.

High temperature resistant thermal insulation for cryogenic tanks

Liquid natural gas is pumped into a main tank until the main tank is completely filled with liquid. Once filled, high pressure gas is pumped into the main tank. This high pressure gas forces the liquid from the main tank into an overflow tank until the liquid level in the main tank reaches a predetermined level. High pressure gas is then pumped through the main tank to the overflow tank until the LNG in the overflow tank is saturated at a pressure slightly higher than the pressure needed at the use device. Once the desired pressure is achieved the delivery of LNG to the delivery system is stopped. LNG is initially delivered from the overflow tank to the use device as a high pressure gas. Some of the high pressure gas being delivered from the overflow tank is diverted from the use device to saturate the LNG in the main tank at the desired pressure. The LNG will be delivered from the overflow tank is depleted and then the LNG will be delivered from the main tank which will have been saturated by the high pressure gas from the main tank.

LNG delivery system

A pressure building circuit for a double-walled tank containing a low temperature fluid, including a settling ring and an orifice between the tank outlet and the pressure building coil for maintaining a minimum pressure.

Growing community of inventors

New Prague, MN, United States of America

Duane Preston