Screw Compressor Oil Injection Port for Pump-Free Oil Flow
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional compressors require an oil pump to maintain oil flow during winter months due to low condensing pressure, risking overheating without it, and existing oil injection ports result in high average pressure ratios within the compression chamber.
Innovation Solution
Designing oil injection ports that inject oil into the compression chamber at specific times to achieve an average pressure ratio less than 1.8:1 relative to suction pressure, eliminating the need for an oil pump by optimizing oil injection timing and configuration.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If conventional oil injection ports are used, then oil enters the compression chamber at high pressure ratios (average 1.8:1), but this requires an oil pump to maintain proper oil flow, especially during winter months
Solution Approach 1:
The oil injection port is positioned to inject oil into the compression chamber before the compression cycle reaches high pressure ratios. By initiating oil injection at lower pressure ratios (when the port first becomes aligned with the compression chamber), the system ensures adequate oil flow without requiring an oil pump, especially during winter months when condensing pressure is low
2Temperature
If oil injection occurs at high pressure ratios (average 1.8:1), then oil flow is maintained during compression, but the compressor risks overheating without an oil pump
Solution Approach 1:
Oil injection is initiated before the compression cycle reaches high pressure ratios, ensuring that cooling oil is introduced into the compression chamber when pressure ratios are lower. This preliminary oil injection maintains adequate cooling throughout the compression cycle without requiring an oil pump, thereby preventing overheating risks
3Stress or pressure
If oil injection ports are positioned for early injection, then average pressure ratio during oil injection is reduced (less than 1.8:1), but oil may not flow sufficiently during winter months with low condensing pressure
Solution Approach 1:
The system utilizes the natural pressure differential created during the compression cycle to drive oil flow through the injection port. By positioning the port to become aligned with the compression chamber at lower pressure ratios, the compression process itself provides the driving force for oil injection, eliminating the need for an external oil pump and ensuring adequate oil flow even during winter months
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
Maintains compressor efficiency without an oil pump, reducing costs and complexity, and enhancing system sustainability by avoiding overheating risks.
Implementation Method 1
The oil injection port that injects oil into the compression chamber during a time period, and an average pressure ratio of the pressure of the compression gasses within the compression chamber relative to the suction pressure during the time period is less than 1.8:1
Data Source
AI summary
Screw compressors and screw compressor systems are disclosed in which the compressors include an oil injection port that injects oil into the compression chamber during a compression cycle. The oil injection port is located in an outer wall of the cylindrical bore within the compressor housing in which the main rotor is rotationally mounted. The oil injection port is located and configured to inject oil into the compression chamber during a time period such that the average pressure ratio of the pressure of the compression gasses within the compression chamber relative to the suction pressure during the time period is reduced as compared to standard compressors. The design of the oil injection port allows screw compressor systems to not include an oil pump.