Views:1 Author:Site Editor Publish Time: 2020-10-21 Origin:Site
Application of ERW welded pipe
1.1 Application of foreign ERW casing
The United States was the first country to use ERW casing and the country that used it the most. The development process of ERW casing application can be roughly divided into three stages:
The first stage is when ERW casing begins to be applied and recognized by the market. In the 1960s, ERW casing began to enter the field of special oil pipes and was recognized for its advantages in quality and price. At that time, ERW casing was only limited to lower steel grades of H40 and J55 casings, and its market share Also lower.
The second stage is the large-scale promotion and use stage of ERW casing. In the early 1980s, with the success of the N80 plate test and the improvement of people's understanding of ERW casing, the application of ERW casing increased rapidly at a rate of 5%-10% per year. Table 2 shows the survey data of the US ERW oil well pipe and seamless oil well pipe application by Preston, an authoritative American pipe statistics agency. Table 2 The statistics of total oil well pipes include oil pipes, casings and drill pipes.
Rods do not need welded pipes, and 7% of it should be deducted. In this way, the proportion of ERW oil and casing applications in the United States has exceeded 50%. Japan’s Nippon Steel Corporation has exported a total of 120 X 104 t of ERW oil well pipes. The longest service life has been 12 years. No users have reported any product quality problems. The proportion of ERW oil and casing applications in France, Russia and other countries has reached 20% -30%.
The third stage is the development stage of ERW casing to special purpose casing and ultra-deep wells. In recent years, ERW casing has penetrated into ultra-deep wells and special applications, such as high S and P and other complex media oil wells. Among them, the φ177.8 mm ERW casing of the United States Iρng Star company has been downhole to a depth of 78∞m, the φ244.5 mm ERW casing of the German Hosi company has been downhole to a depth of 6∞Om, and the ERW casing and tubing of the Canadian Prudential company have reached 600?1 It is widely used in 8∞m gas wells.
1.2 Application of ERW casing in China
Before the 1980s, the casings used in my country's oil and gas fields were all processed with seamless pipes. The introduction and trial of ERW casings began in the late 1980s. In 1985, the former Ministry of Petroleum imported a small number of ERW casings from Japan for testing, most of which were surface casings of J55 steel grade. From 1985 to 1999, my country imported a total of 32 X 104 t of Japanese ERW casing, which has been applied in Daqing, Shengli, Liaohe, Zhongyuan, and Changqing oil fields. The steel grades are J55 and N80, and the casing diameter is 127- 508 mm (5 -20 in). The author has conducted in-depth investigations of all ERW casing users in China on oil wells, downhole depths, construction units, casing specifications, thread types, downhole, cementing time and usage conditions, and summarized and analyzed them.
During the investigation, it was found that all ERW casings, whether they are surface casing, oil layer casing, or deep well test, are in good use and no failure report has been seen. The former Department of Science and Technology of the Ministry of Petroleum Industry organized three units of Daqing Oilfield, Petroleum Tubing Research Institute, and Shengli Oilfield to pass the evaluation and appraisal of "ERW Casing Development and Research and Promotion and Application Project" in 1988. The appraisal opinion is "All" The test results show that ERW casing can not only meet the requirements of surface casing and technical casing, but also meet the technical requirements of oil layer casing. Therefore, this result has high use value and economic benefits. The production cost of ERW casing is low. , The price is cheaper than similar seamless casing. If you use 1/3 of the ERW casing every year, you can save tens of millions of dollars in foreign exchange."
It was mentioned in the report that ERW casing is not suitable for use in oil wells containing H2S and CO2 gas media. However, in the past 10 years, with the continuous development of metallurgical industry technology, the ERW casing produced now can be used in oil and gas wells containing H2S and CO2 gas media.
China National Petroleum Corporation formulated the Petroleum and Natural Gas Industry Standard SY IT 5989-1994 ~ Technical Conditions for Foreign Orders of Longitudinal Welded Pipes in 1994. Affected by international supply channels and our policy (requiring foreign manufacturers to supply more than 10% less than seamless pipes when ordering from abroad), etc., ERW casing has not been widely promoted in China, and its application proportion Less than 5% of the total amount of casing. 0 In 2∞1, the Baoji Petroleum Steel Pipe Plant and Sumitomo Metals Co., Ltd. of Japan, a joint venture, learned from foreign advanced management experience, so that the annual output of the ERW casing production line exceeded 7 X 104 t, and the ERW casing was in The domestic consumption has only been able to increase, and currently has reached 10%. In recent years, the application of ERW casing in the same area is shown in Table 3, and the application of ERW casing in Shengli Oilfield is shown in Table 4.
Most of the domestic ERW casing use is limited to J55 steel grade surface casing. Due to the limited capacity of the production line of Baoji Sumikin Steel Pipe Co., Ltd., it cannot produce N80 steel grade ERW casing, which accounts for 80% of the casing market. The casing has not been widely promoted and applied in China.
Through the promotion and application of ERW casing in China for nearly 20 years, the time for large-scale promotion and application is now ripe.