防返吐保压候凝挤堵封井管柱

对于套损、套窜严重的井,采用目前油田使用的光油管挤注管柱和部分油田使用的单封保护上层挤堵下层管柱,已无法控制堵剂的去向,若候凝时间掌握不好,在起钻时可能出现堵剂返吐,挤堵效果差,同时可能会污染保护层。为此,研制了一种防返吐保压候凝挤堵封井管柱。该管柱由可钻插管封隔器和井下机械开关组成,能实现封隔器下入、坐封、丢手以及堵剂挤入一趟管柱完成,满足地层高压挤堵剂和带压起钻不返吐的施工要求。现场试验表明,该管柱能够用于油水井下部层段堵水堵漏主层上返归位、封堵地层侧钻更新套管、报废井眼填充封井等措施施工中,满足高压挤堵封窜和带压起钻不返吐的施工要求,为老油田挤堵封井工艺提供了技术支持。

一种新型自适应柔性暂堵封隔压裂技术的应用

本文提出一种新型自适应柔性暂堵封隔压裂技术的应用,通过优选产品材料,优化现场施工工艺,提高暂堵成功率,明显提升了压裂改造效果。

囊袋式两端自堵封孔工艺实验效果研究——以焦煤集团中马村矿为例

抽采钻孔封孔质量的优劣直接影响着煤矿回采工作面瓦斯抽采效果。针对国内瓦斯抽采浓度普遍偏低的现状,特引进囊袋式两端自堵封孔工艺以提高瓦斯抽采功效及浓度。本文以焦煤集团中马村矿为例,通过实验探索该工艺在增强瓦斯抽采效果上的优势。

新型复合调剖剂的调制方法与应用分析

在超稠油井中,新型复合调剖剂通过无机复合调堵剂、含油污泥冻胶调剖体系及高温冻胶调剖体系的组合应用,展现出显著的封堵效果和稳定性能,提升了油层动用程度和油井产能。注入时合理控制压力和速度,克服堵塞问题实现分段封堵,优化配方工艺提高调剖剂耐温、化学稳定和抗盐性以适应复杂油藏,实验表明其在高渗透区形成有效封堵层降低渗透率,提高动用效率和产能,未来智能化多功能调剖剂开发将推动油田发展。

泡沫在多孔介质中封堵有效期实验研究

使用玻璃器皿测定的泡沫性能不能反映泡沫在多孔介质中的特性。建议用地层水连续驱替被实验泡沫封堵的岩心,以岩心封堵率保持在80%以上,驱替压力梯度保持在0.4 MPa/m以上的驱替时间为泡沫封堵有效期。实验岩心由露头砂压制而成,尺寸（cm）为75×4.5×4.5,沿长度方向设置3个测压点,将岩心分为4段,岩心孔隙体积500 mL,水测渗透率0.131-0.233μm2。实验起泡液由体积分数1%的阴离子表面活性剂0A、适量稳泡剂、分散剂组成,用模拟地层水配液。实验温度45℃。通过岩心各测压点压力-时间曲线,各段压力梯度-时间曲线,各段封堵率-时间曲线,计论了驱替过程中泡沫行为、形态的变化。测定了平均半衰期7.4 h的泡沫对10个岩心的封堵率和封堵有效期：5个不含油岩心的封堵率在80.3%-94.1%范围,封堵有效期在69.47-108.33 h范围,平均89.30 h;5个残余油饱和度2.3%-6.0%的岩心,封堵率相近,在84.2%-91.6范围,封堵有效期则低得多,在15.55-35.25 h范围,平均25.80 h,表明泡沫堵水不堵油。

爆破作业引起井下瓦斯和煤尘爆炸事故原因分析

本文根据大量的现场调查资料，分析了煤矿井下因爆破作业引起瓦斯爆炸事故的原因，指出炮泥封堵长度不足，爆破电源火花，巷道贯通爆破措施不力，裸露爆破，炸药爆燃和分次爆破是瓦斯爆炸的主要原因．某些班组长重生产轻安全违章指挥，工人违章作业，没有按规程要求执行“一炮三检”制度是产生事故的人为因素。

Welding of shape memory alloy to stainless steel for medical occluder

Dissimilar metal joining between NiTi shape memory alloy（SMA） and stainless steel was conducted.A cluster of NiTi SMA wires were first joined with tungsten inert gas（TIG） welding process,then the NiTi SMA TIG weld was welded to a stainless steel pipe with laser spot welding process.The microstructure of the welds was examined with an optical microscope and the elemental distribution in the welds was measured by electron probe microanalysis（EPMA）.The results show that TiC compounds dispersively distribute in the NiTi SMA TIG weld.However,the amount of TiC compounds greatly decreases around the fusion boundary of the laser spot weld between the NiTi SMA and stainless steel.Mutual diffusion between NiTi shape memory alloy and stainless steel happen within a short distance near the fusion boundary,and intermetallic compounds such as Ni3Ti＋（Fe,Ni）Ti appear around the fusion boundary.

The Role of Transesophageal Echocardiography for Transcatheter Closure of Atrial Septal Defects with the Amplatzer Septal Occluder

Objective: To evaluate of the role of transesophageal echocardiography (TEE)in percutaneous closure of atrial septal defects (ASD) with the Amplatzer septal occluder. Methods:Sixty- two patients (10 to 55 years of age) were selected for percutaneous closure of ASD bytrans-esophageal echocardiography, which was also used to monitor the procedure, to select theappropriate size of the Amplatzer device, to verify its position, and to access the immediateresults of the procedure. During the follow-up, transthoracic echocardiography (TTE) or TEE was usedto evaluate the presence and magnitude of residual shunt (RS), device position, and right cardiacchamber diameters. Results: The mean ASD diameter by TTE ([19. 1 +- 5. 8] mm) was significantlysmaller (P< 0. 001) than the stretched diameter of the ASD (25. 1 +- 6. 4) mm. There are nosignificant differences between the TEE -measured value (23. 5+_6. 2) mm and the stretched diameterof the ASD (P > 0. 05). Due to proper patient selection all procedures were successful. There wasimmediate and complete closure in 61/62 patients, only one patients had trivial residual shunt.Follow- up was performed using TTE or TEE right after operation, 1 d, 1 month, 3 months, 6 monthsand yearly thereafter. Ail, patients remain asymptomatic without any clinical or technical problems.Conclusion: With the aid of TEE, percutaneous closure of ASD can be performed successfully, safely,and effectively.

浅谈电力电缆防火技术

电力电缆是发电厂、变电站维持正常运行的重要组成部分,近年来,电缆火灾事故频繁发生。由于防火措施不完善,着火后蔓延很快,火势凶猛,难以扑灭,不但直接烧损了大量的电缆和设备,而且停电修复的时间很长,严重影响了工业生产和人民生活。本文章主要介绍了电缆防火方面的现状及发展方向。

Transcatheter to Close the Patent Duetus Arteriosus and Atrial Septal Defects in Children

Objective: To evaluate the therapeutic effect, safety and complications oftranscathetering Amplatzer device in the closure of patent ductus arteriosus (PDA) and atrial septaldefects (ASD) in children. Methods: Patients with PDA (n = 25) and ASD ( n = 16), confirmed byechocardiography, were treated by transcatheterization. Amplatzer occluder device was placed by thetranscatheterization with the image support of X-ray and transthoracic echocardiography ( TTE) . TheTTE, ECG and X-ray examination were engaged to evaluate the therapeutic results on the time pointsof 24 h , 1, 3 , 6, 12 months after the operation, and all these cases were engaged to the follow-upexamination. Results: The cardioangiographic diameter was 13.0-28.0 mm ([19.3+-4.9] mm) in ASD and2.0-7.7 mm ([3.9+-1.5] mm) in PDA . The diameter of the Amplatzer occluder selected were 13.0-30.0mm ( [20.6+-5.1] mm) in ASD and 4.0-12.0 mm ([6.6+-1.9] mm) in PDA , respectively. All the Amplatzeroccluders were placed successfully. There were no complications during and after the operation.Very small residual shunt was still found soon after the operation in 10 cases , and there were noresidual or recanalization after three months of the operation. The pulmonary artery pressure andheart size were significantly decreased in follow-up examination . Conclusion: Transcatheteringclosure with Amplatzer device is an effective, simple and safe technique in the treatment of ASD andPDA in children.

Transcatheter closure of coronary artery fistula using Guglielmi detachable coil

Background Coronary artery fistula （CAF） is a rare anomaly.Transcatheter CAF closure has been introduced using various materials,but only few data are available on the Guglielmi detachable coil （GDC）.The advantage of using GDC for transcatheter CAF closure is more controllable,therefore much safer when compared to other coils.This report is about our experience in transcatheter closure of CAF using fibered GDC in our hospital.Methods ＆ Results From 2002 to 2007,there were 10 patients with CAFs （age range：28 to 56 year-old,7 males） who underwent transcatheter CAF closure.There were a total of 19 CAFs which originated from right coronary （n =5）,left circumflex （n =3）,left anterior descending artery （n =10） and left main trunk （n =1）.Median number of coil deployment for each fistula was 3 （range：1 to 6）.The pulmonary artery was the most common site of the distal communication of CAFs （n =14）,followed by right atrium （n =3）,left atrium （n =1） and left ventricle （n =1）.Immediate coronary angiography after GDC deployment revealed no residual shunt in 12 （63.2％） CAFs,significant reduction of the flow in 5 （26.3％）,while 2 （10.5％） could not be closed due to small size.Nine （90％） patients underwent a repeated angiography within 3 to 8 months.Among 12 CAFs that were occluded immediately post-deployment,there were 2 CAFs with insignificant residual flow.Among 6 CAFs with significantly decreased flow immediately post-deployment,2 were occluded totally in the follow-up angiography.In total,12 （70.5％） CAFs were occluded completely and 5 （29.5％） CAFs still had insignificant residual flow,which did not need any additional coil deployment.During a mean follow up of 4.3 ± 0.7 year,all patients remained symptom and complication free.Conclusions The fibered GDC is a safe and effective method for percutaneous closure of the CAFs.

Cardiac resynchronization therapy for heart failure induced by left bundle branch block after transcatheter closure of ventricular septal defect

A 54-year-old female patient with congenital heart disease had a persistent complete left bundle branch block three months after closure by an Amplatzer ventricular septal defect occluder. Nine months later, the patient suffered from chest distress, palpitation, and sweating at daily activities, and her 6-min walk distance decreased significantly （155 m）. Her echocardiography showed increased left ventricular end-diastolic diameter with left ventricular ejection fraction of 37%. Her symptoms reduced significantly one week after received cardiac resynchronization therapy. She had no symptoms at daily activities, and her echo showed left ventricular ejection fraction of 46%and 53%. Moreover, left ventricular end-diastolic diameter decreased 6 and 10 months after cardiac resynchronization therapy, and 6-min walk dis-tance remarkably increased. This case demonstrated that persistent complete left bundle branch block for nine months after transcatheter closure with ventricular septal defect Amplatzer occluder could lead to left ventricular enlargement and a significant decrease in left ventricular systolic function. Cardiac resynchronization therapy decreased left ventricular end-diastolic diameter and increased left ventricular ejection fraction, thereby improving the patient’s heart functions.

Percutaneous transcatheter closure of mitral paravalvular leak via transarterial retrograde approach

Repeat surgery has usually been considered the first choice to solve paravalvular leaks of prosthetic valves, but it cames a high operative risk, a high mortality rate and an increased risk for re-leaks. Percutaneous closure of such defects is possible, and different approaches and devices are used for this purpose. For mitral paravalvular leaks, constructing an arterio-venous wire loop for delivering the closure device through an antegrade approach is the most commonly used technique. Transcatheter closure can also be performed through a transapical approach or retrograde transfemoral arterial approach. We present a case of 68-year-old man with a mitral paravalvular leak that was suc- cessfully closed using an Amplatzer~ Duct Occluder H, via retrograde transfemoral arterial approach under three-dimensional transesophag- eal echocardiographic guidance, without the use of a wire loop. The initial attempt to cross the paravalvular defect was unsuccessful, but the obstacle was finally overcome by introducing complex interventional techniques.

Home-made fenestrated amplatzer occluder for atrial septal defect and pulmonary arterial hypertension

We report the management of a patient with secundum atrial septal defect （ASD） and severe pulmonary hypertension. A 65-year-old male with recently diagnosed atrial septal defect was referred to our centre for decompensated right heart failure with rest and exercise induced dispnea and severe pulmonary hypertension. Right heart catheterization confirmed a mean pulmonary pressure of about 55 mmHg and a Qp/Qs of 2.7. An occlusion test with a compliant large balloon demonstrated partial fall of pulmonary arterial pressure. The implantation of a home-made fenestrated Amplatzer ASD Occluder （ASO） was planned in order to decrease left-to-right shunt and promote further decrease of pulmonary arterial pressure in the long-term. Thus, by means of mechanical intracardiac echocardiography study with a 9F 9 MHz Ultralce catheter （Boston Scientific Corp.）, we selected a 34 mm ASO for implantation. Four millimeter fenestration was made inflating a 4 mm non-compliant coronary balloon throughout the waist of the ASO, which was successfully implanted under intmcardiac echocardiography. After six months, a decrease of pulmonary arterial pressure to 24 mmHg and full compensated right heart failure was observed on transthoracic echocardiography and clinical examination. This case suggests that Wanscatheter closure with home-made fenestrated ASD in elderly patients with severe pulmonary hypertension is feasible.

A case of transcatheter closure of aortopulmonary window using modified double-disk occluder

Aortopuhnonary window is a rare congenital cardiac malformation, which is previously repaired using cardiopulmonary bypass. However, some cases were reported to repair the aortopulmonary septal defect by transcathetcr closure. Here we present a 30 year-old woman with a 7-mm aortopulmonary window, who was successfully treated using a modified double-disk PmVSD occluder

Platypnea-orthodeoxia syndrome in a patient with a pre-existing patent foramen ovale successfully treated with an atrial septal occluder

Platypnea orthodeoxia syndrome is associated with dyspnea and arterial oxygen desamration accentuated by an upright posture. It can be secondary to an intracardiac shunt. We report a case of platypnea-orthodeoxia syndrome （POS） in a 58-year old male patient who had a pre-existing patent foramen ovale （PFO） and substantial pulmonary pathologies. He was successfully treated by percutaneous transcatheter closure of the PFO. Our case highlights the importance of recognition of this rare syndrome in patients who present with unexplained hy- poxia for whom transcatheter closure of the interatrial shunt can be safely carded out.

Percutaneous closure of paravalvular leak in the treatment of anemia of mixed etiology in a patient with diabetic complications and chronic inflammation

Hemolytic anemia after implantation of an artificial mitral valve is a rare but recognized complication of surgery. The presence of paravalvular leak after surgery and the necessity of using oral anticoagulants causes that anemia emerges as a severe and potentially fatal issue.

New method for plugging channeling in oil field by nitrogen foam

In order to present a new method for plugging channeling in oil field,the injection modes and validity period of foam system which plugged the formation water layer were studied by means of the experimental model which simulated the real conditions of oil wells existing channeling.Above all,the influence factors including reservoir pressure,permeability,oil saturation and gas-to-liquid ratio were studied through dynamic experiment.Then,in light of the technology characteristics of foam injection in oil field,the comparison between gas-liquid and liquid-gas injection modes was studied.The result shows that the gas-liquid injection mode can ensure the foam injectivity and plugging performance.The plugging validity of nitrogen foam injected into the formation water layer was evaluated in different plugging pressure gradients by the dynamic method which is more reasonable than the static evaluation method in laboratory.The research demonstrates that the plugging validity period of foam decreases with plugging pressure gradient increasing.If the plugging pressure gradient is 0.15 MPa/m,the validity period is 160 h.Finally,a empirical equation and a plate about the plugging validity and the plugging pressure gradient were obtained for forecasting the validity period of foam.