Are fixed supports required at both ends of a single-wave expansion joint?
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This post was last edited by zhaoqingsheng on 2016-5-10 07:37. The expansion joint in the outlet pipe of one of our company’s hot water network circulation pumps was stretched straight after the pump started operating. Question: For the single-wave expansion joint installed on the outlet pipe of the heat network circulation water pump, is it necessary to install a fixing bracket at the rear end of the expansion joint?
It is not necessary; generally, a support is installed at the inlet end of the expansion joint to prevent the reverse force exerted by expansion on the pump.
When fixed brackets are installed at both ends, the bellows lose their function. The standard practice is to use limit tie rods on bellows expansion joints to prevent excessive compression and stretching; I’m not sure if you have those in place.
The pump outlet should be equipped with a shock-absorbing throat, which functions as a single-wave expansion joint combined with a limit device. If it is just an expansion joint, it will be pulled apart.
If it is a free expansion joint, there will be an issue with the blind plate force. Fixed brackets need to be installed to resist the force of the blind plate. If it is not set, the pipeline will be pulled off course. Or the expansion joint is straightened out, or even damaged. In the case of an expansion joint with tie rods, these rods can balance the force exerted by the blind flange. It is not necessary to use fixed brackets.