Pictures of Hangqi back-pressure steam turbine cat claws – does any member have information on this?
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Pictures of Hangqi back-pressure steam turbine cat claws – what is the principle and structure behind the use of these cat claws, and what should be done during maintenance?
The cat claws that extend forward and backward from the horizontal flange of the lower cylinder are known as the lower-cylinder cat claws, or also as the working cat claws (supporting cat claws). There are two cat claws in front of and behind the lower cylinder of the high-pressure cylinder, each supported on the bearing seats at the front and back of the high-pressure cylinder. The cat’s-paw type supports for the lower cylinder can be further divided into non-midplane supports and midplane supports. The cat’s-claw support for the upper cylinder is referred to as the upper-cylinder cat’s-claw support. It uses a split-plane support mechanism, with the cat’s-claw extensions from the upper-cylinder flange (also known as working cat’s-claws) serving as the load-bearing surfaces that rest on the bearing seat; these load-bearing surfaces lie in the same plane as the horizontal split plane of the cylinder. When the cat’s paws expand due to heat, the center of the cylinder remains aligned with the center of the rotor
During maintenance, tighten the bolts so that they are in close contact with the extended surface of the flange, thereby preventing the lower half of the cylinder from sinking when it is removed. After reassembly, loosen the bolts again
The Smin value is 0.17–0.27, while Smax is 0.34; after adjusting the gap, the spring should be in a state of no stress (installed in the same direction). How should these values be understood?
The image above isn’t very clear; let’s take another one
To prevent the cylinder from being affected by thermal expansion, this bolt on the cat’s paw must not be tightened, otherwise it can easily cause damage to the cylinder
In other words, the bolts cannot be tightened too much; an expansion gap must be left as specified in the drawings
If it’s meant to be moved, of course it can’t be locked
The bolts must be tightened; if there is not enough clearance, the thickness of the outer ring support can be adjusted