JPH0352963Y2 - - Google Patents

Description

[Detailed Description of the Invention] Industrial Application Field The present invention is applied to moving blades of thermal power, nuclear power, and geothermal turbines.

Conventional technology Conventionally, as shown in Figs.
1,02,03,04 T type root blade 09
8, and connects the tenon a on the outer periphery of the rotor blade to the shroud 06. Note that 05 is a stop key.

Problems to be Solved by the Invention In such a conventional example, the shroud 06 was complicated to install, the cost was high, and steam leaked from the joints of the shroud 06.

Therefore, the present invention aims to reduce the production cost and improve performance of the blade by adopting a single blade structure (all the blades in one row are single blades and are not restrained by shrouds, wires, etc.), in other words, by eliminating the shroud. Reduces the number of parts and eliminates shroud installation work,
This is to reduce costs. In addition, a shelf provided in place of a shroud on the outer circumferential side of the rotor blade is continuous all the way around the blade, thereby preventing steam from leaking outside the blade.

Means for Solving the Problems The present invention is to install single blades having a T-shaped blade root on the blade wheel side and a shelf portion on the outer circumference side one after another in the circumferential direction from a vertical groove for installing the blades on the outer circumference of the impeller. In the turbine rotor blade, the assembly is completed by a serration blade stopping device consisting of a serration blade, which is the final installed blade, and a stop key, in which the shelf portions of the single blade and the serration blade are mutually connected to each other. The turbine rotor blade is characterized in that a connection piece is welded to the ledge of the single blade at the stop key drive point to achieve close contact with the adjacent ledge.

Embodiments The present invention will be explained with reference to embodiments shown in FIGS. 1 to 4.

In Figures 1 to 4, insert the T-shaped blade root 9 of the regular blade 1 through the blade insertion vertical groove c, and then insert the required number of blades in order between the stop keys 5 (in the opposite direction to the serration blade stop device described below). . In addition, there is a shelf b on the outer periphery of the normal blade 1.
has. After that, the six wings of the wing stop group between the stop keys 5 are implanted.

Serration blade 2 of the serration blade stop device,
Serration wing 3 among 3 and 4 is the final implantation wing. When installing this, the stop key 5 is removed, and after the wing 3 is installed, the stop key 5 is driven in from the outer periphery of the wing to assemble the serrations of the wing stop device. Therefore, a space equivalent to the thickness of the stop key 5 is created between the wings m-n and the wings p-q. In order to make this space the same as the shelf b of the other wings, the connecting piece 7 is attached to the shelf b of the wings m and p by welding d.

Function: By welding the connecting pieces 7 to the blades m and p, a damping effect works even when the blades vibrate, suppressing an increase in amplitude.

In other words, in a single blade structure, when a blade vibrates, the shelf part b of the blade comes into contact with the shelf parts b of the adjacent blades on both sides, which causes a damping effect, suppresses the increase in amplitude, and prevents vibration accidents of the blade. To prevent.

Effects of the invention: The connecting pieces can be attached easily and inexpensively by welding.

Also, since the shelf is continuous all around the blade, steam will not leak out of the blade. Furthermore, a single blade structure with a T-shaped blade root and a serration blade stop device can be employed in a steam turbine blade row.

[Brief explanation of the drawing]

Figure 1 is a front view of the present invention, Figure 2 is a cross-sectional view of Figure 1, Figure 3 is a cross-sectional view of Figure 4, and Figure 4 is a cross-sectional view of Figure 1. of-
FIG. 5 is a front sectional view of the conventional example, and FIG. 6 is a sectional view taken from - in FIG. 5. 1... Normal wing, 2, 3, 4... Serration wing, 5... Stop key, 7... Connection piece, 8... Wing wheel,
b...shelf part, c...blade embedded vertical groove, d...welding,
m, n, p, q...stop key drive part wing.

Claims (1)

[Scope of utility model registration request] Individual blades having a T-shaped blade root on the impeller side and a shelf on the outer circumferential side are implanted one after another in the circumferential direction from the blade installation vertical groove on the outer circumference of the impeller, and the final implanted blade is a serration blade. In a turbine rotor blade whose assembly is completed by a serration blade stop device comprising a stop key and a stop key, the shelf portions of the individual blade and the serration blade are brought into close contact with each other, and the stop key is driven into the blade. A turbine rotor blade characterized in that a connecting piece is welded to a shelf part of a single blade at a certain point to achieve close contact with an adjacent shelf part.