Build-Own-Operate Air Supply Cuts Specific Power 31% at an Auto Fuel-System Plant

The client is an automotive parts manufacturer in Wuhan that makes plastic fuel tanks, fuel-injection lines and complete fuel-system assemblies. These processes, especially fuel-tank blow moulding and welding, need compressed air at stable pressure and low moisture content. Any interruption or drop in air quality can stop the line or scrap whole batches.

The plant’s compressed air station was failing on three fronts:

• Summer shutdowns. Air-cooled compressors tripped on high temperature during hot, humid summer months, which stopped production.
• High failure rate. Two of the old compressors were worn and unreliable.
• Rising electricity costs. The old station ran at a specific power of 0.2 kWh/Nm³.

The upgrade was delivered under a build-own-operate (BOO) model. The air-service provider invested in, installed, owns and maintains the equipment. The plant pays only for the compressed air it actually uses and made no upfront investment.

• Compressors: after the plant’s air-demand profile was measured, the two old compressors were replaced by two high-efficiency SIND screw compressors. They have a cooling configuration rated for high-temperature, high-humidity operation.
• Air treatment: the old dryers were replaced by two SIND ChillDry CD series refrigerated dryers and a new air receiver was added. This stabilises the pressure dew point and reduces pipeline pressure loss.
• Monitoring: an IoT platform tracks pressure, flow and power in real time, with alarms for abnormal conditions, accessible from mobile devices and PCs.

• Specific power reduced from 0.2 to 0.138 kWh/Nm³, a 31% energy saving.
• About 400,000 kWh of electricity saved per year, based on the plant’s annual air consumption.
• No high-temperature shutdowns since the upgrade, so production plans run on schedule.
• More stable air quality, with less variation in blow-moulding and welding and a lower reject rate.
• No capital outlay and no maintenance burden for the plant under the BOO contract.

Combining efficient, heat-tolerant compressors with proper drying and a pay-per-use model solved the plant’s reliability and cost problems together.