CN110911147A

CN110911147A - Single grounding installation method of transformer clamp for small-capacity 35kV station

Info

Publication number: CN110911147A
Application number: CN201911241211.3A
Authority: CN
Inventors: 周亮; 薛建平; 关银环
Original assignee: Wujiang Transformer Co Ltd
Current assignee: Wujiang Transformer Co Ltd
Priority date: 2019-12-06
Filing date: 2019-12-06
Publication date: 2020-03-24

Abstract

The invention relates to the technical field of transformers, in particular to a method for independently grounding and installing a small-capacity 35kV station transformer clamping piece. The upper clamping piece and the lower clamping piece of the high voltage and the low voltage are connected through the tensioning screw rod, so that the clamping pieces are independently grounded. The method avoids breaking the insulation, saves the time for workers to drop the insulation of the bags, sleeve the paper tubes, place the rubber pads and the insulation paper boards, reduces the process flow, saves the materials and reduces the cost.

Description

Single grounding installation method of transformer clamp for small-capacity 35kV station

Technical Field

The invention relates to the technical field of transformers, in particular to a method for independently grounding a transformer clamping piece for a small-capacity 35kV station.

Background

A transformer is a device that changes an alternating voltage using the principle of electromagnetic induction, and main components are a primary coil, a secondary coil, and an iron core (magnetic core). The main functions are as follows: voltage transformation, current transformation, impedance transformation, isolation, voltage stabilization (magnetic saturation transformer), and the like. According to the application, the method can be divided into: power transformers and special transformers (furnace transformers, rectification transformers, power frequency test transformers, voltage regulators, mining transformers, audio transformers, intermediate frequency transformers, high frequency transformers, impact transformers, instrument transformers, electronic transformers, reactors, mutual inductors, etc.).

The existing 35kV small-capacity oil-immersed station transformer has no special requirements, the clamping piece is not independently grounded, and the clamping piece, the pad and the bottom of the oil tank are grounded through one point of the oil tank. The existing independent grounding mode of the clamp realizes independent grounding through insulating of the pad foot, the oil tank and the tank bottom positioning nail, the tank bottom positioning nail wraps an insulating cylinder, and the pad foot of the clamp body is in insulating fit with the tank bottom. When the transformer body falls into the box, the travelling crane shakes, the transformer body pad feet cannot be accurately matched with the positioning nails, and the pad feet easily collide with the phenolic paper tubes of the insulating parts wrapped on the positioning nails at the bottom of the box. In addition, the oil tank has small space, hand holes need to be formed in the oil tank, the time for wrapping insulation, paper tube sleeving, rubber pad placing and insulation paperboard on the positioning nails by operating personnel is long, the operation is inconvenient, and potential safety hazards also exist.

Disclosure of Invention

In order to solve the technical problems, the invention discloses a method for independently grounding and installing a small-capacity 35kV station transformer clamping piece, which overcomes the defects that an oil tank is small in space, a window is not formed, and a transformer body falls on a tank pad to collide and damage positioning insulation, so that the insulation quality is ensured and the total assembly time is shortened.

The invention adopts the following specific technical scheme: a method for installing a small-capacity 35kV station transformer clamping piece in an independent grounding mode includes welding an inclined washer at a positioning hole of a high-voltage lower clamping piece and a positioning hole of a pad foot, drilling a hole after welding, matching with an insulating washer to enable the lower clamping piece to be insulated from the pad foot, connecting the high-voltage lower clamping piece with the high-voltage lower clamping piece through a tensioning screw rod to achieve independent grounding of the clamping piece, fixing the lower clamping piece on the pad foot through a bolt, sequentially arranging a wood cushion block and a pad foot insulator between the lower clamping piece and the pad foot, sequentially arranging the inclined washer and the insulating washer in a gap between the lower clamping piece and a bolt nut, and enabling the section of the insulating washer to be 7-shaped.

The invention has the beneficial effects that: the invention avoids breaking the insulation, saves the time for workers to drop the insulation of the bags, sleeve the paper tubes, place the rubber pads and the insulation paper boards, reduces the process flow, saves the materials and reduces the cost.

Drawings

Figure 1 is a small capacity 35kV station installed using the present invention.

Fig. 2 is an enlarged schematic view of the plane a-a in the figure.

Fig. 3 is a schematic structural diagram of a lower clip part in the prior art.

Fig. 4 is a schematic view of the structure of transformer body foot pad and box bottom insulation fit in the prior art.

Detailed Description

For the purpose of enhancing the understanding of the present invention, the present invention will be described in further detail with reference to the accompanying drawings and examples, which are provided for the purpose of illustration only and are not intended to limit the scope of the present invention.

Example (b): as shown in figures 1 and 2, the method for independently grounding the variable clamp for the small-capacity 35kV station comprises the steps of welding an inclined washer at a positioning hole of a high-voltage lower clamp and a positioning hole of a pad foot, drilling a hole after welding to be matched with an insulating washer, so that the lower clamp is insulated from the pad foot, connecting the high-voltage lower clamp and the high-voltage lower clamp through a tensioning screw rod, and independently grounding the clamps, wherein the lower clamp is fixed on the pad foot through a bolt, a wood cushion block and a pad foot insulator are sequentially arranged between the lower clamp and the pad foot, the inclined washer and the insulating washer are sequentially arranged in a gap between the lower clamp and a bolt nut, and the section of the insulating washer is in a 7 shape.

In the prior art, the 35kV small-capacity oil-immersed substation has no special requirement, the clamping piece is not independently grounded, and the clamping piece, the pad and the bottom of the oil tank are grounded through one point of the oil tank. As shown in fig. 3, the existing clamp is separately grounded by insulating the pad foot from the oil tank and the tank bottom positioning nail, the tank bottom positioning nail is wrapped by an insulating and insulating cylinder, and the pad foot of the body is in insulating fit with the tank bottom (see fig. 4). When the transformer body falls into the box, the travelling crane shakes, the transformer body pad feet cannot be accurately matched with the positioning nails, and the pad feet easily collide with the phenolic paper tubes of the insulating parts wrapped on the positioning nails at the bottom of the box. In addition, the oil tank has small space, hand holes need to be formed in the oil tank, the time for wrapping insulation, paper tube sleeving, rubber pad placing and insulation paperboard on the positioning nails by operating personnel is long, the operation is inconvenient, and potential safety hazards also exist.

In the embodiment, the inclined gasket is welded at the positioning holes of the clamping piece and the pad under high and low voltages, and after welding, the inclined gasket is matched with the drilled hole and matched with the insulating gasket, so that the clamping piece and the pad are insulated. The upper clamping piece and the lower clamping piece of the high voltage and the low voltage are connected through the tensioning screw rod, so that the clamping pieces are independently grounded (see figure 1). The method avoids breaking the insulation, saves the time for workers to drop the insulation of the bags, sleeve the paper tubes, place the rubber pads and the insulation paper boards, reduces the process flow, saves the materials and reduces the cost.

The foregoing illustrates and describes the principles, general features, and advantages of the present invention. It will be understood by those skilled in the art that the present invention is not limited to the embodiments described above, which are described in the specification and illustrated only to illustrate the principle of the present invention, but that various changes and modifications may be made therein without departing from the spirit and scope of the present invention, which fall within the scope of the invention as claimed. The scope of the invention is defined by the appended claims and equivalents thereof.

Claims

1. A method for installing a small-capacity 35kV station transformer clamping piece in an independent grounding mode is characterized in that an inclined gasket is welded at a position of a positioning hole of a high-voltage lower clamping piece and a positioning hole of a pad, a drilling hole is drilled after welding and matched with an insulating gasket to insulate the lower clamping piece from the pad, and the high-voltage lower clamping piece and the low-voltage upper clamping piece are connected through a tensioning screw rod to achieve independent grounding of the clamping pieces.

2. The method for separately grounding a transformer clamp for a small-capacity 35kV station according to claim 1, wherein the lower clamp is fixed on a foot pad through a bolt, and a wood pad block and a foot pad insulator are sequentially arranged between the lower clamp and the foot pad.

3. The method for separately grounding a small-capacity 35kV station transformer clamp according to claim 2, wherein a bevel washer and an insulating washer are sequentially arranged in a gap between the lower clamp and the bolt and the nut.

4. A single grounding installation method of a small-capacity 35kV substation transformer clamp according to claim 3, wherein the cross section of the insulating washer is 7-shaped.