本文選題：石油鉆桿接頭 + 精密塑性成形�。� 參考：《上海工程技術大學》2015年碩士論文

【摘要】：隨著全球能源需求增加,能源緊缺,以石油為代表的一次能源的開采難度增加,對鉆具的技術要求也隨之增高。石油鉆具屬于易耗型工業(yè)產品,工作環(huán)境惡劣,受力條件復雜,受到扭曲、拉伸、沖擊等復合力的作用,對材料及其加工技術的要求較高。本文以石油鉆具中的典型零件鉆桿接頭為研究對象,接頭的材料為37CrMnMo中碳低合金鋼。接頭是鉆桿的重要連接部件,在鉆井過程中要經常拆卸,受到大鉗絞合力的作用,受力條件復雜。傳統(tǒng)的成形工藝為半自由鍛成形,尺寸精度低、材料消耗大、能源消耗高,內部金屬流線容易受到破壞。以溫擠壓為代表的精密塑性成形是一種少無切削的塑性成形方法,零件精度高,可以部分去除后道切削加工工序,且有利于改善金屬內部流線分布狀態(tài),鍛件質量和力學性能顯著提高。本文采用精密塑性成形技術,可提高鍛件尺寸精度和材料利用率,改善鍛件質量,降低能源消耗。通過熱物理實驗,分析石油鉆桿接頭用鋼材料在高溫時的流變性能,得出變形溫度(T)及應變速率(ε)對金屬流變應力(σ)的影響規(guī)律,在此基礎上,根據(jù)Arrhenius方程及對熱壓縮數(shù)據(jù)的分析,得應力指數(shù)n=6.56091642以及熱激活能Q=284.039529KJ/mol,建立了37CrMnMo鋼高溫流動時的應力本構方程。對石油鉆桿接頭成形工藝進行分析,確定分模面、加工余量、公差、拔模斜度及關鍵成形部位的圓角半徑,建立合適的物理模型。從預制坯形狀及連皮位置關鍵參數(shù)入手,以解決鍛件充不足,金屬流動阻力大,鍛件內部溫度分布不均的問題。從變形溫度(T)、擠壓速度(V)、臺階處圓角半徑(r)入手,以獲得鍛件成形規(guī)律,提高鍛件質量,降低成形載荷�；趧傉乘苄杂邢拊�,對石油鉆桿接頭精密塑性成形過程進行模擬。分析不同預制坯形狀及連皮位置對鍛件的溫度場、應力及應變場、載荷情況、金屬流動情況、金屬內部流線分布的影響,綜合得出最優(yōu)預制坯形狀及連皮位置。研究石油鉆桿接頭精密塑性成形過程中工藝參數(shù)因素對鍛件質量的影響。采用正交試驗,分析了零件成形溫度(T)、壓力機速度(V)、臺階處圓角半徑(r)等工藝參數(shù)對最大等效應力、載荷及溫度場的影響。通過極差分析及綜合平衡分析,獲得了石油鉆桿接頭37CrMnMo鋼溫擠壓精密成形中各參數(shù)的影響顯著性,得到了最優(yōu)工藝參數(shù)組合：溫度為780℃,擠壓速度為30mm/s,臺階處圓角半徑為4mm。將最優(yōu)條件下的模擬結果進行分析并應用于實際生產中,對分析結果進行實驗驗證,結果表明,該條件下生產的制件符合實際要求。本文對石油鉆桿接頭實際生產中的工藝優(yōu)化及鍛件質量問題的研究,對于提高鍛件組織性能,進一步改變成形工藝提供理論依據(jù)及指導。
[Abstract]:With the increase of global energy demand and energy shortage, it is more difficult to exploit primary energy represented by oil, and the technical requirements of drilling tools are also increased. Oil drilling tools are consumable industrial products. The working environment is bad, the stress conditions are complex, and they are affected by the complex forces such as distortion, tension, impact, etc., so the requirements for materials and their processing technology are higher. In this paper, the typical drill pipe joint of petroleum drilling tools is studied. The material of the joint is 37CrMnMo medium carbon low alloy steel. The joint is an important connecting part of drill pipe. It is often disassembled during drilling and is subjected to the action of the force of the forceps, so the stress condition is complicated. The traditional forming process is semi-free forging, which has low dimensional precision, large material consumption, high energy consumption, and internal metal streamline is easy to be destroyed. Precision plastic forming, represented by warm extrusion, is a kind of plastic forming method with little cutting and no cutting. The precision of parts is high, the back cutting process can be partially removed, and the streamline distribution in metal can be improved. The quality and mechanical properties of forgings are greatly improved. In this paper, the precision plastic forming technology is used to improve the dimension precision and material utilization ratio of forgings, improve the quality of forgings and reduce the energy consumption. In this paper, the rheological properties of steel materials used in oil drill pipe joints at high temperature are analyzed through thermophysical experiments. The effects of deformation temperature (T) and strain rate (蔚) on metal rheological stress (蟽) are obtained. Based on the Arrhenius equation and the analysis of the thermal compression data, the stress exponent nv 6.56091642 and the thermal activation energy QF 284.039529KJ / mol are obtained. The stress constitutive equation of 37CrMnMo steel under high temperature flow is established. The forming process of oil drill pipe joint is analyzed, and a suitable physical model is established by determining the parting surface, machining allowance, tolerance, drawing die inclination and the radius of the corner of the key forming position. Based on the key parameters of the preform and the position of the connecting skin, the problems of insufficient filling of the forgings, large metal flow resistance and uneven internal temperature distribution of the forgings are solved. Starting from the deformation temperature (T), extrusion speed (V) and (r) of the corner radius at the step, the forming rule of the forgings is obtained, the quality of the forgings is improved and the forming load is reduced. Based on rigid viscoplastic finite element method, the precision plastic forming process of oil drill pipe joint is simulated. The effects of different preform and position of preform on the temperature field, stress and strain field, load, metal flow and the distribution of flow line inside metal are analyzed, and the optimum preform and concatenation position of preform are obtained. The influence of process parameters on forging quality in the process of precision plastic forming of drill pipe joint is studied. The effects of forming temperature (T), press speed (V) and corner radius (r) on the maximum equivalent stress, load and temperature field are analyzed by orthogonal test. By means of range analysis and comprehensive balance analysis, the influence of various parameters on the precision forming of 37CrMnMo steel is obtained. The optimum technological parameters are as follows: the temperature is 780 鈩，

本文編號：2109803