Pressure relief valve with field-replaceable high corrosion-resistant components

A valve structure for a port in a vessel wall comprising:

• a housing removably mountable on the vessel wall in a mounted condition adjacent to the port,
• a corrosion-resistant insert removably carried by and secured to the housing independently of its mounting on the vessel wall and defining a passage communicating with the port when the housing is in its mounted condition,
• a valve seat on the insert adjacent to the passage,
• a seal assembly removably carried by the housing independently of the insert for movement between an open condition and a closed condition closing the passage,
• a gasket encircling the port and engageable with the insert for cooperation therewith to isolate the housing from contents of the vessel when the seal assembly is in its closed condition, and
• bias structure biasing the seal assembly to its closed condition,
• the housing in its mounted condition and the gasket cooperating with the vessel wall for supporting the insert so that during operation of the valve structure the insert is subjected to substantially only compressive forces.

A valve structure for a port in a vessel wall comprising:

• a housing removably mountable on the vessel wall in a mounted condition adjacent to the port,
• a corrosion-resistant insert removably carried by and secured to the housing independently of its mounting on the vessel wall and defining a passage communicating with the port when the housing is in its mounted condition,
• a valve seat on the insert adjacent to the passage,
• a guide structure mounted on the housing,
• a valve stem removably receivable in the guide structure for guided contact therewith during movement between opening and closing positions, and
• a seal assembly removably coupled to the valve stem independently of the insert for movement therewith between an open condition and a closed condition closing the passage,
• the housing in its mounted condition cooperating with the vessel wall for supporting the insert so that during operation of the valve structure the insert is subjected to substantially only compressive forces.