JPS6117937A - Apparatus for water pressure test - Google Patents

Abstract

PURPOSE:To improve the closing condition of the discharge part side of an impeller by constituting the apparatus for water pressure test by combining a test ring with a seal ring so as to be expandable with vertical sliding motion by the inner pressure according to the expansion of the seal part. CONSTITUTION:A water pressure testing apparatus consisting of a cylindrical test ring 6 and cylindrical seal ring 7 fitted slidably with one end edge of the outer peripheral wall thereof is brought into contact with the seal part 5 of an impeller 4 of a vortex chamber 1. Gaskets 8, 9, 10 are respectively inserted to each contact face of the test ring 6, seal ring 7 and casing and also are fastened by a jack bolt 11. When pressure is applied with filling a water inside the casing, the seal part 5 is expanded vertically and accordingly the test ring 6 and seal ring 7 are expanded sliding each other vertically, so the discharge side part of the impeller 4 of the inside of the casing is closed at all times.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a hydraulic test device for closing the volute chamber of a pump or water wheel.

(Prior Art) A conventional water pressure testing instrument will be explained based on FIG. 2. Figure 2 is a sectional view of an upper shaft spiral centrifugal pump. Pressurize to the required pressure and perform a water pressure test.

(Problem to be Solved by the Invention) However, the part to which high pressure is applied during operation of the pump is outside the seal 5 part of the impeller 4 where the discharge pressure acts,
The suction side and back pressure side of the impeller 4 are usually not subject to pressure resistance testing. Nevertheless, there is a problem in that the central part of the casing must be made thicker and more robust than actually necessary for the above-mentioned water pressure test.

(Means for Solving the Problems) The present invention aims to eliminate the above-mentioned problems and perform a rational water pressure test. It is a combination of a cylindrical test ring that is separated from the center of the casing and closed, and a cylindrical seal ring that is slidably attached to one end edge of the outer peripheral wall of the test ring in a fluid-tight manner. The present invention provides a water pressure testing device characterized by its configuration.

(Function) That is, a water pressure testing device consisting of a test ring and a seal ring is brought into contact with the seal portion of the impeller, and as the seal portion expands, the internal pressure causes them to slide toward each other and downward. Due to the expansion, the discharge side of the impeller in the casing, which is surrounded by the volute chamber and the casing cover, is always obstructed.

(Invention type N-Okiban effect) With such a structure and operation, only the portion to be tested for pressure resistance is pressurized, and a reasonable water pressure test can be performed.

(Example) The structure and operation of the present invention will be specifically explained based on an example shown in FIG. Figure 1 (a) is a cross-sectional view of the casing of a vertical centrifugal centrifugal pump closed with a hydraulic test device to which the present invention is applied, and Figure 1 (b) is a partial view of the casing. A water pressure testing instrument consisting of a test ring 6 and a seal ring 7 is brought into contact with the seal 5, and the discharge side of the impeller in the casing surrounded by the swirl chamber 1 and the casing cover 2 is closed. The seal ring 7 is slidably joined to one end edge of the outer circumferential wall of the tenu ring 6, and the tenu ring 6 and the casing, the ring ring 7 and the casing, the test ring 6 and the seal ring 7
8, 9, and 10 are inserted into each joint surface to maintain watertightness.

When the inside of the closed casing is filled with water and pressurized, the casing swells outward due to the internal pressure and both sea/I
15 expand upward and downward, respectively, and the seal ring 7 and test ring 6 also expand - respectively due to internal pressure.
1. Slide each other downward and spread out. This is because there is a difference in the radius R from the casing center of the gaskets 8, 9, and 10 inserted into the joint surfaces of the seal ring 7 and the test ring 6, and the seal ring 7 has a radius difference R8-R.
This is because the test ring 6 is pushed upward by the internal pressure acting on its horizontal inner surface corresponding to the radius difference R1 (+-R,) and downward by the internal pressure acting on its horizontal inner surface corresponding to the radius difference R1 (+-R, respectively. A jack bolt 11 screwed onto the outside of the ring 6 is used to assist in sliding the test ring 6 and the seal ring 7 smoothly. The discharge side of the impeller is always blocked.

[Brief explanation of the drawing]

FIG. 1 is a cross-sectional view of the casing of a vertical-shaft centrifugal centrifugal pump that has been blocked by a hydraulic test device to which the present invention is applied, and FIG. 2 is a cross-sectional view of the vertical-shaft centrifugal pump.

Claims (1)

[Claims] A cylindrical test ring that separates and closes the volute chamber of the pump or water wheel from the center of the casing in a hydraulic test device for the casing of a pump or water wheel, and a liquid-tight connection to one end edge of the outer peripheral wall of the test ring. A water pressure testing instrument characterized by comprising a cylindrical seal ring and a cylindrical seal ring that is slidably mounted.