Refrigeration Apparatus Blocking Valve to Reduce Refrigerant Leak Risk
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing refrigeration apparatuses face challenges in effectively managing refrigerant leaks across utilization units, as control valves may allow refrigerant flow even when closed, potentially leading to further leaks and safety concerns.
Innovation Solution
A refrigeration apparatus with a blocking valve and controllable control valves in the gas-side connection pipe and branch pipes, allowing for precise control of refrigerant flow and reducing the risk of further leaks by blocking refrigerant supply when a leak occurs.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of operation
If a control valve is used to switch refrigerant flow in utilization units, then the refrigerant flow can be individually controlled, but the valve may allow refrigerant to pass even in closed state, leading to potential further leaks
Solution Approach 1:
The system divides the refrigerant flow control into two separate functional components: a control valve for flow regulation and a blocking valve for complete shut-off. This segmentation allows each valve to specialize in its function, with the blocking valve ensuring complete isolation when the control valve fails to close properly.
Solution Approach 2:
The blocking valve acts as an intermediary safety device between the control valve and the utilization unit. It provides an additional layer of protection by ensuring complete refrigerant isolation even when the control valve's closed state is insufficient.
2Productivity
If a valve with minute flow path is used for oil collection, then refrigeration oil can be collected to compressor, but refrigerant continues to flow to leaked unit reducing safety
Solution Approach 1:
The system separates the oil collection function from the refrigerant flow control function. The control valve manages refrigerant flow while the blocking valve provides complete shut-off capability, allowing oil collection through controlled minute flow paths without compromising safety through uncontrolled continuous flow.
Solution Approach 2:
The system allows partial refrigerant flow through the control valve for normal operation and oil collection, but provides the capability for complete shut-off when needed for safety, accepting some excessive control capacity to ensure safety requirements are met.
3Adaptability or versatility
If control valves are individually controlled in each utilization unit, then refrigerant flow directions can be switched, but safety is reduced when leaks occur due to continued flow through closed valves
Solution Approach 1:
The system implements a dual-valve configuration in each utilization unit, segmenting the flow control into a control valve for adaptability and a blocking valve for safety. This allows the system to maintain flow direction switching capability while ensuring complete isolation when leaks occur.
4Reliability
If blocking valve is disposed in first gas-side connection pipe between heat source unit and branch portions, then refrigerant supply can be reduced to affected units, but device complexity increases
Solution Approach 1:
The blocking valve is positioned at the connection pipe level before branch portions, segmenting the system into manageable isolation zones. This strategic placement allows effective leak mitigation while avoiding the need for complex valve arrangements within each utilization unit.
Data Source
Figure 1
Figure 2
Figure 3
AI summary
Provided is a refrigeration apparatus in which a refrigerant leak is reduced. The refrigeration apparatus includes a heat source unit (10); a plurality of utilization units (30) connected in parallel to the heat source unit; a refrigerant-flow-path switching unit (40) that includes a plurality of first gas-side control valves (42) each of which switches a flow of refrigerant in a corresponding one of the utilization units and that individually switches a flow of refrigerant in each of the utilization units; a first gas-side connection pipe (52) that is disposed between the heat source unit and each of the first gas-side control valves and through which high-pressure gas refrigerant flows; a plurality of first gas-side branch pipes (521) each of which is included in the first gas-side connection pipe, communicates with a corresponding one of the utilization units, and has one of the first gas-side control valves disposed therein; and a blocking valve (65) that is disposed in the first gas-side connection pipe and blocks a flow of refrigerant. The first gas-side connection pipe includes a plurality of branch portions (BP2) connected to the first gas-side branch pipes, and the blocking valve is disposed between the heat source unit and each of the branch portions.