Method of controlling radial clearences when assembling turbines

The invention relates to measuring equipment and can be used to control radial clearances in turbomachines during assembly or disassembly.

The purpose of the invention is to increase the information content and accuracy of control.

In FIG. 1 shows a diagram of a device that implements the proposed method; in FIG. 2a - dependence of the radius of the inner surface of the shell E_aboutb from the angle of rotation of the rotor; in FIG. 26 is a diagram of the distribution of gaps for each blade for a partially and fully assembled turbomachine.

The radial clearance control device contains gaps sensors 1 and 2, moreover, the sensor 1 is installed between adjacent rotor blades 3, and the sensor 2 is installed in the stator shell 4. The end face of the sensor with the sensing element is installed at the same level with the inner surface of the shell. The angular position β of the sensor 1 is taken to be zero, the angle increases clockwise. The number of rotor blades is N (in FIG. 1 and 2 N = 12), the blade with the number 1 = 1 is located in the direction of the positive angle at the angular distance /? (equal to half the pitch of the blades _th 1 360° _t .

/ 51 = '—N— · Thus, the angular position of the blade with the number η is determined by the expression n 1 360 °,, 360 °

R^{n =} 2 '' ~ TG ^(η_1)

The angular position ^ of the sensor 2 is assumed to be zero, the positive direction of the angle is clockwise.

The device operates as follows.

At the beginning of the assembly, the sensor 1 is placed on the rotor of the turbomachine, and the sensor 2 on the stator.

The rotor is installed relative to the stator so that the blade with the number N (in the drawing, number 12) is under the sensor 2, and the sensor 1 occupies an angular position relative to the stator

1663404 A1

<td>1 360 ° * ”= 2 N</td><td>the center of rotation of the wheel, respectively, for partially Rnn and fully Ren of the assembled engine (Fig. 26)</td>

In this position, the gap dp is measured between the sensor 1 and the shell at the point &lt;ru, and the gap ό_ΛΝ between the sensor 2 and the end face of the blade N, the sensor signals are transmitted to the recording equipment.

The rotor is rotated clockwise and in the position when the blade with the number N-1 (in Fig. 1 and 2 with the number 11) is under the sensor 2, the gaps &lt;5λν-ι are measured and is completed, d. '

The angular position of the points on the shell, to which the gap is measured by the sensor 1, is determined by the following expression,

Ρι =

360°

N + (1-1)

360°

N where I is the measurement number.

After performing N measurements with sensors 1 and 2, sensor 1 is removed and the final assembly of the turbomachine is carried out. Then re-measure the gaps using the remaining sensor 2 between this sensor and all the blades d_DrugsP.

As a result, based on the gaps, we can also construct the dependence of the radius of the inner surface of the shell R₀6 from the angle φ (Fig. 2a).

I

Ro6-fl = RDi + other (1) where Rpi is the distance (radius) from the center of rotation of the wheel to the end face of the sensor 1 (indicated by g in Fig. 2a).

By clearances for_l._Pand d_lare determined by the removal (radius) of the ends of the blades from

Rn.n- Ro6o- dln (2) (indicated by □ in FIG. 26),

Rncn⁼ Ro6o ~ dncn (3) (denoted by G in Fig. 26), where Ro6o = Rpi + dpif₀ - radius of the inner surface of the shell at 0:

dpi-f_e- the gap between the shell and sensor 1 at φ = 0. &lt;

Comparing the measurements of radial clearances taken at the beginning of the assembly and at the end of it, their change is monitored taking into account the influence of the setting of bearings 20 deformations of bearings and the housing. This method allows you to reliably and accurately control the gaps on each blade relative to the body, which increases its information content.