Online repair method for asbestos type expansion joint of pipeline

Abstract

The invention discloses an online repair method for an asbestos type expansion joint of a pipeline, and the method comprises the following steps: firstly, manufacturing two bracket disks, wherein the centers of the bracket disks are provided with through holes and the outer rings of the bracket disks are provided with shoulders; respectively welding the bracket disks at the outer rings of two flanges which are connected with the two ends of the expansion joint; welding a first press plate which is provided with screw holes at intervals between the two ends of the two bracket disks; screwing bolts into the screw holes; wrapping a nickel-chromium ceramic fiber cloth at the outer rings of the two bracket disks and overlapping; coating the overlapped position with a sealant and positioning on the first press plate; pressing a second press plate which is provided with through holes at intervals on the first press plate; ensuring the bolts on the first press plate to penetrate through the overlapped position of the nickel-chromium ceramic fiber cloth and the through holes of the second press plate and screwing down by utilizing nuts; and arranging two cushion blocks respectively at the shoulders of the two bracket disks and tightly pressing the cushion blocks, the nickel-chromium ceramic fiber cloth and the shoulders of the bracket disks by virtue of bolts. In the method disclosed by the invention, online repair is carried out on the expansion joint of the pipeline, and the pipeline is prevented from being damaged because of expansion with heat and contraction with cold; and the method has the advantages of simplicity and convenience in construction and low cost, and guarantees the continuous delivery of a pipeline medium, thereby guaranteeing normal production.

Description

technical field [0001] The invention relates to an online repair method for asbestos-type expansion joints of pipelines. Background technique [0002] In order to avoid damage caused by thermal expansion and contraction of long-distance pipelines, asbestos-type expansion joints connected by flanges are usually installed on the pipelines. The expansion joints expand or contract with high or low temperature to ensure the integrity of the pipeline. Since most of the pipelines are installed in the field, the non-metallic asbestos cloth of the expansion joint is damaged by long-term high-temperature sunlight and natural aging, resulting in the failure of the expansion joint, which may cause a decrease in the sealing performance of the pipeline; usually, when the expansion joint is damaged, replace it with a new one. It is necessary to break the line during the replacement, which leads to the stoppage of the pipeline and affects the normal production; at the same time, the new pro...

AI Technical Summary

Problems solved by technology

Since most of the pipelines are installed in the field, the non-metallic asbestos cloth of the expansion joint is damaged by long-term high-temperature sunlight and natural aging, resulting in the failure of the expansion joint, which may cause a decrease in the sealing performance of the pipeline; usually, when the expansion joint is damaged, replace it with a new product. The line needs to be disconnected during the replacement, which leads to the suspension of the pipeline and affects the normal production; at the same time, the new products usually replaced can use bellows type expansion joints or carbon steel inner and outer sleeve type expansion joints, but the cost of bellows type expansion joints is high. It will greatly increase the maintenance cost. However, the carbon steel inner and outer sleeve type expansion joints are heavy and difficult to replace. For large pipelines, crane construction is required

Replacement of new products requires pipeline stoppage operation, and it is obviously impossible to replace new expansion joints for pipelines that do not allow stoppage

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