JPS5882097A - Axial hydraulic machine - Google Patents

Abstract

PURPOSE:To make it possible to prevent the titled machine from damages even when the top ends of movable and stationary vanes are brought into contact with a casing and the root of the movable vane by a method wherein a slide member made of an alloy metal is attached to the top end of each of the movable vane and the stationary vane and the like slide member is attached to the root of the movable vane opposing to the top end of the stationary vane. CONSTITUTION:The slide members 7a and 7b each made of a soft alloy metal having a high degree of adhesiveness such as a Babbit metal are fitted in a dovetail groove 6a in the root 3a and in a dovetail groove 6b in the top end 3b, respectively, of the movable vane 3. Likewise, a slide member 8 is attached to the top end of the stationary vane 4 in the like manner as in the case of the movable vane 3. With the above structure, even when the slide members 7b and 8 at the top ends of both of the movable vane 3 and the stationary vane 4 are brought into contact with the inner peripheral surface of the case 2 and the root of the movable vane 3, only the slide members 7b and 8 are abraded. Accordingly, the movable vane 3 and the stationary vane 4 are prevented from damages and at the same time, a gap (b) between the movalble vane 3 and the case 2 and a gap (c) between the stationary vane 4 and the root of the movalbe vane 3 from becoming larger than predetermined values, respectively, during rotation.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an axial flow fluid machine including moving blades attached to a rotor and stationary blades attached to a case.

An axial flow compressor is a type of axial flow fluid machine, as shown in Figs. 1 and 2.
h blade 31 and stationary blade 4 attached to the inner peripheral surface of case 2
The structure consists of an alternating combination of `` and ``.

The centrifugal force of the rotor 1 rotating at a high speed of 10,000 rl) m, bending stress due to air flow, vibration, etc. act on the rotor blade.

4IK Since fi#A3' is pulled in one radial direction by the above centrifugal force, the attachment groove 5 provided in the rotor 1 and the rotor blade root 3
Depending on the fit with 'a', the movable member 83' escapes from the mounting groove 5, so that the rotation diameter of the tip of the lIh blade increases.

This enlargement of the rotational diameter is extremely difficult to avoid due to deformation within the elastic range of the rotor 1 and the rotor blade 3' even if the fitting is an interference fit.

Generally, from the standpoint of efficiency, the gap b between the rotor blade 3/ and the case 2 is determined by taking into account elongation due to centrifugal force and thermal expansion.
' is preset to a minimum value so as not to contact the case 2. Considering the case where the rotor blade 3' comes into contact with the case 2, the inner circumferential surface of the case 2 has a rotational width of g 3 / as shown in FIG. A corresponding sliding member 6, for example a soft material such as Babbitt, is cast or fitted.

However, since the fit between the rotor blade attachment groove 5 and the rotor blade root 3'1 varies widely depending on processing tolerances and errors, the amount of escape in the radial direction due to centrifugal force, that is, the rotation radius The amount of expansion differs for each wing. Since the material of the sliding member 6 is softer than that of the rotor blade 3, the tip of the rotor blade 3' that escaped from the mounting groove 5 during one rotation and the sliding member 6 attached to the inner circumferential surface of the case 2 are easily connected to each other. Due to contact, the sliding member 6 is connected to the rotor blade 3
It is removed by the tip of . For this reason, when the escape amount of jl[3' is zero or small, the gap b between the rotor blade 3' and the case 2 is further enlarged, which may further reduce the efficiency.

Also, regarding the relationship between the tip of the stator blade 41, the outer diameter of the rotor 1, and the root portion 37a of the rotor blade, the stator blade 4'
The gap C between the tip of the blade and the blade root portion 3'1 is set to a minimum. However, the stationary blade 4 attached to case 2
I is a root portion 31a of the rotor blade 3' which escaped from the mounting groove 5 due to centrifugal force during rotation.The present invention aims to solve the above-mentioned drawbacks. The axial flow fluid machine is equipped with a stator vane, characterized in that a sliding member is attached to the tip of one or both of the rotor vane and the stator vane.

Embodiments of the present invention will be described below with reference to the drawings.

4 and 5 are a plan view and a front view of the rotor blade used in this embodiment. The rotor blade 43 is provided with a dovetail groove 6a at its root portion 3a, and has a double tail shape at its tip portion 3b. A dovetail groove 6b is provided. The dovetail grooves 6a, 6
b is a sliding member 7a.

7b, a soft alloy material having adhesive properties, such as Babbitt, is fitted respectively. These sliding members 7a, 7b
As mentioned above, without providing the dovetail grooves 6a and 6b, the base part 3a and the tip 3 of the Ijt3 can be directly moved with adhesive.
They may be adhered to b.

Figure #g6 and Figure 7 are a plan view and a front view of the stator blade used in this example, and the stator blade 4 has the above-mentioned Wh on its tip.
A sliding member 8 is attached like Jlt3. The configuration of the axial fluid machine including the ll11g3 and stationary blades 4 having such a structure is the same as the conventional example shown in FIGS. 1 and 2, so one drawing and explanation will be omitted.

Since the present invention is configured as described above, even if the sliding members 7b and 8 attached to the tip of the fiJI (3 and the stationary blade 4) contact the inner circumferential surface of the case 2 and the base of the lIJ blade due to centrifugal force, Since the sliding members 7b and 8 only wear out, it is possible to prevent the moving blades 3 and the stationary blades 4 from being damaged and causing an accident. Since the gap b and the gap C between the base part 3a of the Jl14 and the lIh14 are zero, this is not only advantageous in terms of the efficiency of the compressor, but also the gaps b and c expand beyond the set gap during rotation. -I1.!
can.

As explained above, according to the present invention, even if the tips of the rotor blade and the stator blade come into contact with the case and the base of the rotor blade, respectively, during operation, it is possible to prevent damage from occurring. Furthermore, it is possible to prevent the gaps between the moving blade and the case and between the stator blade and the root of the moving blade from expanding beyond the set gap during operation.

[Brief explanation of the drawing]

Figures 1 and #I2 are a sectional view of a conventional axial flow compressor and an enlarged detailed sectional view of its main parts, Figure 3 is an improved sectional view of the case in Figure 1, and Figures 4 and 5 are from this book. FIGS. 6 and 7 are plan views and front views showing one embodiment of the rotor blades used in the trickle-flow fluid machine of the invention, and FIGS. It is a front view. 3... Moving blade b3a... Root part, 4... Stationary blade, 7a
, 7b. 8...Sliding member. Agent Patent Attorney Toshiyuki Usuda YJl 2nd Figure 3 Momme 3 ¥34 per day Figure 5! -(- f v77 mouth

Claims (1)

[Scope of Claims] 1. In an axial flow fluid machine including a moving blade attached to a rotor and a stator blade attached to a case, a sliding member is attached to the tip of one or both of the moving blade and the stator blade. A trickle fluid machine characterized by: 2. The trickle fluid machine according to claim 1, characterized in that a sliding member is attached to the base of the rotor blade facing the tip of the stationary blade. 3. The axial flow fluid machine according to claim 1 or 2, wherein the sliding member is made of an alloy material.