What is the scope of application for the bolt torque chart? Is it applicable in all situations?
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Is the reference table for bolt torque applicable in all situations? Are flange bolts, cylinder head bolts, foundation bolts for motor pumps, and so on all suitable? Also, after applying lubricant or anti-seize agents, does the bolt torque need to be reduced accordingly? By how much, generally?
There is no torque chart that applies to all operating conditions~~~~~ The tightening force of bolts depends on many factors, such as the material of the flanges, the operating temperature and pressure, as well as the material and structure of the gaskets. Additionally, the strength grade of the bolts also plays a role. Torque charts merely indicate the recommended torque for a particular bolt under certain operating conditions; exceeding this value may result in tensile forces that exceed the bolt’s elastic limit, or it may cause deformation of the thread surface.
In other words, it depends on the installation requirements of the equipment
I remember that according to GE’s standards, the required torque value decreases after applying an anti-galling agent
The bolt torque chart is not applicable in all situations; generally, equipment manufacturers provide a torque chart during installation based on the actual operating conditions, to guide the installation process
This post was last edited by yxmqh on 2024-2-26 at 14:42; it is for reference only
Lubricants and anti-galling agents are generally used in harsh environments and high-temperature conditions; they are usually not needed in normal environments.
Yes, we mainly use it in gas turbine engines, in high-temperature environments
The tightening method that causes the least damage to bolts is actually the stretching method, which is reliable
Yes, for the installation of the couplings between our gas turbines and load gearboxes, we use a hydraulic pulling method
Shenmu cylinder covers, Shaanxi Blower cylinder mid-separation surfaces, reciprocating machine big-end bearing pin shafts, the connecting mechanisms between the reciprocating machine crosshead and piston rod, etc. – for the bolts used in the symmetrical arrangement of large rotating equipment, hydraulic tensioning is generally the method employed for tightening them