Abstract: Methods, apparatus, systems and articles of manufacture are disclosed for leak detection from a thief hatch. An example thief hatch includes a vent control stem coupled to first and second sealing plates, the first and second sealing plates to control fluid flow through the thief hatch based on translation of the vent control stem, and an indicator extending from the vent control stem to provide a visual indication of a condition of the fluid flow.

Abstract: Methods, apparatus, systems and articles of manufacture are disclosed for leak detection from a thief hatch. An example thief hatch includes a vent control stem coupled to first and second sealing plates, the first and second sealing plates to control fluid flow through the thief hatch based on translation of the vent control stem, and an indicator extending from the vent control stem to provide a visual indication of a condition of the fluid flow.

Abstract: Apparatus to protect sealing surfaces of thief hatches are disclosed. An example apparatus includes a first portion that is attachable to a tank, wherein the first portion includes a first opening, and a second portion that is pivotably coupled to the first portion. The example apparatus is structured to provide access to an aperture in the tank via the first opening when the second portion is in an open state and maintain a pressure of the tank within a specified range by selectively separating one or more seals from one or more corresponding sealing surfaces when the second portion is in a closed state, wherein the second portion includes the one or more seals and the one or more corresponding sealing surfaces.

Abstract: Thief hatches with diaphragm assisted sealing are disclosed. An example apparatus includes a base attachable to a tank, and a cover attachable to the base via a hinge. The example apparatus further includes a vacuum seal assembly couplable to the cover, and a diaphragm coupled to a stem of the vacuum seal assembly. The diaphragm is moveable in response to a pressure differential between a first pressure within the tank and a second pressure exterior to the tank.

Abstract: Apparatus to protect sealing surfaces of thief hatches are disclosed. An example apparatus includes a first portion that is attachable to a tank, wherein the first portion includes a first opening, and a second portion that is pivotably coupled to the first portion. The example apparatus is structured to provide access to an aperture in the tank via the first opening when the second portion is in an open state and maintain a pressure of the tank within a specified range by selectively separating one or more seals from one or more corresponding sealing surfaces when the second portion is in a closed state, wherein the second portion includes the one or more seals and the one or more corresponding sealing surfaces.

Abstract: Apparatus to protect sealing surfaces of thief hatches are disclosed. An example apparatus includes a base attachable to a tank around an aperture in the tank. The example apparatus further includes a spacer supported by a support surface of the base. The example apparatus also includes a cover selectively moveable between a closed position covering the aperture and an open position providing access to the aperture, the spacer separating the cover from the base.

Abstract: Apparatus to protect sealing surfaces of thief hatches are disclosed. An example apparatus includes a base attachable to a tank around an aperture in the tank. The example apparatus further includes a spacer supported by a support surface of the base. The example apparatus also includes a cover selectively moveable between a closed position covering the aperture and an open position providing access to the aperture, the spacer separating the cover from the base.

Abstract: Thief hatches with diaphragm assisted sealing are disclosed. An example apparatus includes a base attachable to a tank, and a cover attachable to the base via a hinge. The example apparatus further includes a vacuum seal assembly couplable to the cover, and a diaphragm coupled to a stem of the vacuum seal assembly. The diaphragm is moveable in response to a pressure differential between a first pressure within the tank and a second pressure exterior to the tank.