Tightening of high-pressure bolts

As a reminder, if it is necessary to open the device for maintenance, apply anti-seize paste to the tightened bolts to facilitate disassembly and save time on maintenance

Hydraulic stretchers are mainly used for the main bolts of equipment or bolts with larger diameters, right?

This post was last edited by Laojiu on 2011-2-10 at 14:03. Reply: 1 What methods are used to preload the bolts of high-voltage equipment? Hydraulic wrench? It is selected according to the operational requirements (process pipelines) or the client’s requirements. 2. Which is generally preferred, a hydraulic wrench or a stretcher? If funding permits, using multiple stretchers simultaneously results in high efficiency and excellent pre-tensioning effects. 3. Studs for high-pressure pipe flanges (HGT20613, 20634-2009): If pre-tightening is carried out using a hydraulic tensioner (HG-T21573.1-1995 series of hydraulic bolt tightening devices), it seems that a relatively long length of studs is required; the length specified in the pipe flange standards may not be sufficient. How can pre-tightening be achieved? One end of the bolt should protrude from the surface of the nut by 1 time the bolt diameter; if this amount is not sufficient but the manufacturing process requires stretching, hydraulic nuts can be used as a reference.