Bearing Temperature Guidelines for Axial Split Case Pumps

Maintaining the correct bearing temperature is essential to ensuring the efficient operation and long service life of a split case pump and other centrifugal pumps. Bearings are critical components that support the pump shaft and allow smooth rotation under varying loads and speeds. When bearings overheat, it can lead to lubrication failure, mechanical wear, and ultimately, pump failure.

This article provides a comprehensive overview of bearing temperature standards for axial split case pumps, the typical reasons for abnormal temperature rises, and recommended troubleshooting and treatment methods. It references key Chinese industrial standards and practical guidelines to ensure proper operation and compliance.

Standard Regulations for Split Case Pump Bearing Temperature

Based on national and industry standards, the following limits apply to split case pump bearings under normal ambient conditions (assumed 40°C):

Category	Standard / Cause	Requirement / Description	Recommended Action / Notes
Bearing Temperature Standards	GB3215-82	Max allowable bearing temperature during operation: 80°C	Monitor during operation
	JB/T5294-91	Temperature rise ≤ 40°C above ambient; absolute max 80°C	Monitor and maintain proper cooling
	JB/T6439-92	Built-in bearing: ≤ 20°C above medium temp, max 80°CExternal bearing: rise ≤ 40°C above ambient	Ensure correct bearing placement and cooling
	JB/T7255-94	Temp rise ≤ 35°C, max temp 75°C	Follow manufacturer guidance
	JB/T7743-95	Temp rise ≤ 40°C, max temp ≤ 80°C	Use temperature monitoring
	JB/T8644-1997	Max temp rise: 35°C, max bearing temp: 80°C	Regular inspection recommended
Motor Bearing Standards	Rolling bearings	Max temperature: 95°C	Infrared thermometer check
	Sliding bearings	Max temperature: 80°C	Infrared thermometer check
	Temp rise	Should not exceed 55°C above ambient	Monitor per schedule
Insulation Impact	F-class with B-class evaluation	Temp rise usually controlled at 80K (resistance) / 90K (component)	At 40°C ambient, max motor temp: 120–130°C
Measurement Tip	–	Use infrared thermometer to check bearing outer surface	For 4-pole motors, bearing temp < 70°C; motor body temp usually stable
Common Causes of Bearing Overheating	Misalignment / Bent Shaft	Shaft center misaligned or bent	Re-align shaft; straighten or replace if needed
	Loose Foundation Bolts	Vibration or improper installation	Re-tighten bolts; check installation stability
	Dirty Lubrication Oil	Contaminants reduce lubrication efficiency	Drain and refill with clean, recommended oil
	Expired Lubricant	Oil degradation from prolonged use	Flush bearing housing; replace with fresh oil
	Damaged Bearing Components	Cracked/damaged balls or rollers	Replace with correct spec bearings
Maintenance & Monitoring Tips	–	Ensure proper alignment, lubrication, and vibration monitoring	Use infrared temp guns; schedule routine lubrication; follow manufacturer guidelines

Conclusion

Bearing temperature is a vital performance parameter in the operation of a split case pump. Ensuring that the temperature stays within the prescribed limits not only prevents mechanical failures but also extends the equipment’s lifecycle. Following standard regulations, using proper monitoring tools, and executing timely maintenance can significantly reduce the risk of overheating and pump breakdowns.

By adhering to these industry-recognized standards and best practices, operators and maintenance teams can enhance the reliability and efficiency of axial split case pumps in a wide range of applications.