高级检索

兆瓦级煤矿井下压裂泵系统的研制及应用

Research and application on Megawatt level intelligent fracturing pump system in coal mine

  • 摘要: 为满足在坚硬难垮落顶板治理、瓦斯抽采增透等领域大面积区域压裂应用中对流量、压力的需求,研制了一套兆瓦级煤矿井下压裂泵系统。该系统将自动控制和变频技术同煤矿井下压裂泵的设计相结合,能够根据煤矿井下水力压裂的不同阶段的工况需求,动态采集压裂泵性能参数数据,实时分析压裂泵的功率匹配,实现压裂过程全自动化。重点攻克了高压大流量压裂泵特殊材料及工艺、动力端可靠性、液力端可靠性以及自动控制等关键技术瓶颈。研究了适用于压裂极端工况要求的高强度、耐冲蚀马氏体沉淀硬化不锈钢,并采用超高压自增强处理,提高压裂泵液力端疲劳寿命;研究压裂泵齿轮传动及摩擦副等关键可靠性技术,实现兆瓦级功率条件下压裂泵传动系统的高可靠运行;通过计算机仿真,优化了压裂泵液力端吸排液系统的结构、性能;攻克了深钻孔低频变流量坐封技术、煤岩层起裂自动识别技术及循环压裂控制技术,实现压裂全流程的自动化控制该系统分别在曹家滩矿122110特厚煤层工作面和东李煤矿1250瓦斯治理巷进行了工业性试验;曹家滩矿试验显示:坚硬顶板预裂弱化治理裂缝扩展压力平稳,稳压时压力最高可达32.4 MPa,平均流量可达100 m3/h;东李煤矿瓦斯增透试验结果显示,实施水力压裂增透工艺10 d后,平均瓦斯抽采纯量增大到1.596 m3/min,约为对比验证普通钻孔抽采工艺的29倍。

     

    Abstract: This paper presents the development of a megawatt-scale intelligent fracturing pump system for underground coal mines, designed to address the escalating demands for flow and pressure in large-scale regional fracturing applications, particularly in hard roof management and enhanced gas extraction permeability. The system integrates automatic control and variable frequency technology with the design of underground coal mine fracturing pumps, enabling dynamic collection of performance parameter data at various stages of hydraulic fracturing. It provides real-time analysis of the power matching for electrically driven fracturing pumps and achieves full automation of the fracturing process. Key technological challenges, such as the development of special materials for high-pressure, high-flow-rate fracturing pumps; the reliability of the transmission system and hydraulic ends for megawatt-level fracturing pumps; and intelligent control technology, have been successfully addressed. The research included: Development of high-strength, erosion-resistant martensitic precipitation hardening stainless steel suitable for extreme conditions with large flow, ultra-high pressure, and sand-mixed media, along with ultra-high pressure self-reinforcing treatment to enhance the fatigue life of the hydraulic ends of fracturing pumps; Investigation of critical reliability technologies, including high-strength welding for alloy steel, high-load-bearing, high-power-to-weight ratio gear transmission technology, and wear-resistant friction pairs of aluminum bronze alloy-cast iron, to ensure the reliability of the transmission system under high-power conditions; Creation of a high-durability metal plunger-combination seal fracturing fluid sealing pair, with the application of computer simulation technologies such as virtual prototyping, FEA, CFD, and hydraulic system simulation to optimize the structure, performance, and reliability of the fracturing pump's fluid end suction and discharge systems; Mastery of technologies such as low-frequency variable flow sealing for deep boreholes, automatic identification of coal and rock layer fracturing, and cyclic fracturing control, enabling intelligent control throughout the fracturing process. The industrial trial of this system has been successfully conducted at the Caojiatan coal mine 122110 extra-thick coal mine working face for weak zone management of hard roof strata and at the Dongli coal mine 1250 gas control lane for high-efficiency extraction of anti-reflection gas in coal seam areas. Field tests demonstrated that at the Caojiatan coal mine, pre-splitting treatment for hard roofs achieved stable fracture expansion pressure with a maximum of 32.4 MPa and an average flow rate of 100 m3/h. At the Dongli Coal Mine, the gas permeability enhancement test revealed that after 10 days of hydraulic fracturing, the average pure gas extraction volume increased to 1.596 m3/min, approximately 29 times that of the conventional drilling extraction process.

     

/

返回文章
返回