青霉素类抗生素概述

青霉素类抗生素概述 主要内容: 一、青霉素由来 二、结构特点 三、抗菌作用机制 四、分类 五、不良反应 六、青霉素临床应用 七、青霉素使用现状 一 、 青霉素由来 首先先来看看青霉素的由来,早在唐朝的时候,长安城的裁缝会把长有绿毛的糨糊涂在被剪刀划破的手指上来帮助伤口愈合,就是因为绿毛产生的物质(青霉素)有杀菌作用,这也是人们and performance test copies of the record. If necessary, review should be carried out; 4) for spring hangers (included simple spring, hangers and constant support hangers) it should also be recognized as setting and locking of loads. 5) check the surface quality, folded layering and without cracks, rust and other defects. 5) after completion of the test and control drawing number one by one, by series baled. Color alloy steel parts, the parts marking installation location and rotation about the direction you want. 7.3.14. hangers installation 7.3.14.1 hanger layout a. a clear design of hanger should be installed strictly in accordance with the drawings and designs shall not be installed wrong, missing, etc. B. own arrangement of piping support and hanger set and selection should be based on comprehensive analysis of general layout of piping systems; cold installation of steam pipe with particular attention reserved for compensation of thermal expansion displacement and orientation. C. support systems should be rational to withstand pipe loads, static load and incidental load; reasonable piping displacement; guaranteed under various conditions, stress are within the allowed range. Strength, stiffness, and meet requirements to prevent vibration and soothing water, without affecting the adjacent equipment maintenance and other piping installation and expansion. D. equipment connected to the interface to meet pipeline thrust (torque) limit requirements; increase the stability of piping systems to prevent pipeline ... Tube wall thickness (mm) 2-3 4-6 7-10 weld form no slope mouth weld strengthening height h (mm) 1-1.5 1.5-2 weld width b (mm) 5-6 7-6 has slope mouth weld strengthening height h (mm) 1.5-2 2 weld width b (mm) cover had each edge slope mouth about 2 mm argon arc welding weld strengthening surface height and width tube wall thickness (mm) 2--3 3--4 5--6 weld form weld strengthening height h (mm) 1-1 .5 1.5-2 2-2.5 width b (mm) 最早使用青霉素类药物来杀菌。但是当时他并不知道绿毛里产生 的哪种物质,也不知道这种物质的作用机理,而是根据自己日常 的生活发现出来的生活经验。那么青霉素最开始是如何被发 现和产生的呢?它的作用机制又是什么呢?下面让我们带着这两 个问题一起来探索一下青霉素的奥秘! and performance test copies of the record. If necessary, review should be carried out; 4) for spring hangers (included simple spring, hangers and constant support hangers) it should also be recognized as setting and locking of loads. 5) check the surface quality, folded layering and without cracks, rust and other defects. 5) after completion of the test and control drawing number one by one, by series baled. Color alloy steel parts, the parts marking installation location and rotation about the direction you want. 7.3.14. hangers installation 7.3.14.1 hanger layout a. a clear design of hanger should be installed strictly in accordance with the drawings and designs shall not be installed wrong, missing, etc. B. own arrangement of piping support and hanger set and selection should be based on comprehensive analysis of general layout of piping systems; cold installation of steam pipe with particular attention reserved for compensation of thermal expansion displacement and orientation. C. support systems should be rational to withstand pipe loads, static load and incidental load; reasonable piping displacement; guaranteed under various conditions, stress are within the allowed range. Strength, stiffness, and meet requirements to prevent vibration and soothing water, without affecting the adjacent equipment maintenance and other piping installation and expansion. D. equipment connected to the interface to meet pipeline thrust (torque) limit requirements; increase the stability of piping systems to prevent pipeline ... Tube wall thickness (mm) 2-3 4-6 7-10 weld form no slope mouth weld strengthening height h (mm) 1-1.5 1.5-2 weld width b (mm) 5-6 7-6 has slope mouth weld strengthening height h (mm) 1.5-2 2 weld width b (mm) cover had each edge slope mouth about 2 mm argon arc welding weld strengthening surface height and width tube wall thickness (mm) 2--3 3--4 5--6 weld form weld strengthening height h (mm) 1-1 .5 1.5-2 2-2.5 width b (mm) 6 APA HHSCHOH 3 1 CCRCNC2165 CH3B A 43 CNCCOR2二、青霉素类结构特点 OHO青霉素自20世纪40年代 酰胺酶青霉素酶作用点投入使用以来，一直是应 作用点 用广泛和重要的一类抗生 素，基本结构如右图所示， 由母核6-APA(6-氨基青霉烷酸) 和侧链组成。 母核结构—青酶烷酸(双环结构) (β-内酰胺环 并 氢化噻唑环) ,其中β-内酰胺环为维持抗菌活性的最基本结构。 二环的张力都比较大，其稳定性极差，易受到亲核性或亲电性试剂的进攻，使β-内酰胺环破裂，导致青霉素失效并产生致敏物。由于临床上抗菌的需要，人们对侧链上的R经结构改造接上不同的基团，形成各种性能更好的半合成青霉素。 三、抗菌作用机制 (1)通过竞争性抑制细菌的青霉素结合蛋白(PBPs)??细胞壁的粘肽合成受阻??细菌细胞壁缺损??大量的水分涌进细and performance test copies of the record. If necessary, review should be carried out; 4) for spring hangers (included simple spring, hangers and constant support hangers) it should also be recognized as setting and locking of loads. 5) check the surface quality, folded layering and without cracks, rust and other defects. 5) after completion of the test and control drawing number one by one, by series baled. Color alloy steel parts, the parts marking installation location and rotation about the direction you want. 7.3.14. hangers installation 7.3.14.1 hanger layout a. a clear design of hanger should be installed strictly in accordance with the drawings and designs shall not be installed wrong, missing, etc. B. own arrangement of piping support and hanger set and selection should be based on comprehensive analysis of general layout of piping systems; cold installation of steam pipe with particular attention reserved for compensation of thermal expansion displacement and orientation. C. support systems should be rational to withstand pipe loads, static load and incidental load; reasonable piping displacement; guaranteed under various conditions, stress are within the allowed range. Strength, stiffness, and meet requirements to prevent vibration and soothing water, without affecting the adjacent equipment maintenance and other piping installation and expansion. D. equipment connected to the interface to meet pipeline thrust (torque) limit requirements; increase the stability of piping systems to prevent pipeline ... Tube wall thickness (mm) 2-3 4-6 7-10 weld form no slope mouth weld strengthening height h (mm) 1-1.5 1.5-2 weld width b (mm) 5-6 7-6 has slope mouth weld strengthening height h (mm) 1.5-2 2 weld width b (mm) cover had each edge slope mouth about 2 mm argon arc welding weld strengthening surface height and width tube wall thickness (mm) 2--3 3--4 5--6 weld form weld strengthening height h (mm) 1-1 .5 1.5-2 2-2.5 width b (mm) 菌体内??细菌肿胀、破裂、死亡 。 (2)触发自溶酶活性，使细菌溶解。 四、分类 常见的有以下三种: 天然青霉素 半合成青霉素(耐酶青霉素、广谱青霉素) (一)、 天然青霉素 由青霉菌培养液提取获得，含有5种(X、F、G、K、双氢F)，其中以青霉素G性质较稳定，作用最强，低毒价廉，可用于治疗敏感菌所致的各种感染。目前市场上常见的有两种:注射用青霉素钠和注射用苄星青霉素。 下面以青霉素最广泛使用的青霉素G(苄青霉素)为例来进行说明。 药理特性: 繁殖期杀菌药 抗菌作用: 主要用于G+菌、G-球菌、螺旋体，放线菌感染，对G-杆菌不敏感。 作用特点:不耐酸、不耐酶、窄谱 适应症: 1.G+菌感染:肺炎球菌、葡萄球菌、链球菌(溶血性链球菌、草绿色链球菌)、肠球菌白喉杆菌、炭疽杆菌、破伤风杆菌、产气夹膜杆菌等。 2.G-球菌:脑膜炎双球菌、淋球菌。 3.螺旋体:梅毒、钩端、回归热螺旋体。 and performance test copies of the record. If necessary, review should be carried out; 4) for spring hangers (included simple spring, hangers and constant support hangers) it should also be recognized as setting and locking of loads. 5) check the surface quality, folded layering and without cracks, rust and other defects. 5) after completion of the test and control drawing number one by one, by series baled. Color alloy steel parts, the parts marking installation location and rotation about the direction you want. 7.3.14. hangers installation 7.3.14.1 hanger layout a. a clear design of hanger should be installed strictly in accordance with the drawings and designs shall not be installed wrong, missing, etc. B. own arrangement of piping support and hanger set and selection should be based on comprehensive analysis of general layout of piping systems; cold installation of steam pipe with particular attention reserved for compensation of thermal expansion displacement and orientation. C. support systems should be rational to withstand pipe loads, static load and incidental load; reasonable piping displacement; guaranteed under various conditions, stress are within the allowed range. Strength, stiffness, and meet requirements to prevent vibration and soothing water, without affecting the adjacent equipment maintenance and other piping installation and expansion. D. equipment connected to the interface to meet pipeline thrust (torque) limit requirements; increase the stability of piping systems to prevent pipeline ... Tube wall thickness (mm) 2-3 4-6 7-10 weld form no slope mouth weld strengthening height h (mm) 1-1.5 1.5-2 weld width b (mm) 5-6 7-6 has slope mouth weld strengthening height h (mm) 1.5-2 2 weld width b (mm) cover had each edge slope mouth about 2 mm argon arc welding weld strengthening surface height and width tube wall thickness (mm) 2--3 3--4 5--6 weld form weld strengthening height h (mm) 1-1 .5 1.5-2 2-2.5 width b (mm) 4.放线菌感染:但对大多数的G-杆菌无效，对金葡菌产生的β-内酰胺酶不稳定 。 【药物相互作用】: 与丙磺舒合用?效能? 与氨基苷类合用?协同，但不能混合静注 与抑菌药合用?效能? 不能与重金属，铜、锌、汞配伍 不能与氨基酸营养液合用 半合成青霉素 1、口服青霉素类:苯氧青霉素类 青霉素? (penicillin V) 非奈西林 (phenethicillin) 特点: 1) 耐酸不耐酶 2) 可口服 3) 抗菌谱与青霉素同，用于轻症感染 2.耐酶青霉素类 苯唑西林 (oxacillin) 氯唑西林 (cloxacillin) 双氯西林 (dicloxacillin) 氟氯西林 (flucloxacillin) 特点: 耐酸耐酶 and performance test copies of the record. If necessary, review should be carried out; 4) for spring hangers (included simple spring, hangers and constant support hangers) it should also be recognized as setting and locking of loads. 5) check the surface quality, folded layering and without cracks, rust and other defects. 5) after completion of the test and control drawing number one by one, by series baled. Color alloy steel parts, the parts marking installation location and rotation about the direction you want. 7.3.14. hangers installation 7.3.14.1 hanger layout a. a clear design of hanger should be installed strictly in accordance with the drawings and designs shall not be installed wrong, missing, etc. B. own arrangement of piping support and hanger set and selection should be based on comprehensive analysis of general layout of piping systems; cold installation of steam pipe with particular attention reserved for compensation of thermal expansion displacement and orientation. C. support systems should be rational to withstand pipe loads, static load and incidental load; reasonable piping displacement; guaranteed under various conditions, stress are within the allowed range. Strength, stiffness, and meet requirements to prevent vibration and soothing water, without affecting the adjacent equipment maintenance and other piping installation and expansion. D. equipment connected to the interface to meet pipeline thrust (torque) limit requirements; increase the stability of piping systems to prevent pipeline ... Tube wall thickness (mm) 2-3 4-6 7-10 weld form no slope mouth weld strengthening height h (mm) 1-1.5 1.5-2 weld width b (mm) 5-6 7-6 has slope mouth weld strengthening height h (mm) 1.5-2 2 weld width b (mm) cover had each edge slope mouth about 2 mm argon arc welding weld strengthening surface height and width tube wall thickness (mm) 2--3 3--4 5--6 weld form weld strengthening height h (mm) 1-1 .5 1.5-2 2-2.5 width b (mm) 可口服，血浆蛋白结合率高，不易透过血脑屏障 双氯西林作用最强 主要用于耐青霉素G的金葡菌感染 药理特性:抗菌谱和青霉素相仿，但抗菌作用较差，其对青霉素酶稳定，因产酶而对青霉素耐药的葡萄球菌对本类药物敏感，但甲氧西林耐药的葡萄球菌对本类药特耐药。 适应症:主要用于除甲氧西林以外的产青霉素酶的葡萄球菌感染，如败血症、脑膜炎、呼吸道感染、软组织感染等,也可用于溶血性链球菌或肺炎链球菌与耐青霉素葡萄球菌的混合感染。 代表药物:阿莫西林双氯西林钠胶囊 双氯西林为耐酶青霉素弥补了 阿莫西林不耐的酶缺点， 起到了协同抗菌作用， 增强了抗菌活性， 大大增加了抗菌谱。 临床应用 (1)呼吸道感染:急性咽炎、化脓性扁桃体炎、急慢性气管炎、支气管炎、肺炎、感冒继发感染; (2)消化道感染:肝胆系统感染、急性胃肠炎、伤寒、副伤寒; (3)泌尿生殖系统感染:尿道炎、膀胱炎、肾盂肾炎、淋病、软性下疳; and performance test copies of the record. If necessary, review should be carried out; 4) for spring hangers (included simple spring, hangers and constant support hangers) it should also be recognized as setting and locking of loads. 5) check the surface quality, folded layering and without cracks, rust and other defects. 5) after completion of the test and control drawing number one by one, by series baled. Color alloy steel parts, the parts marking installation location and rotation about the direction you want. 7.3.14. hangers installation 7.3.14.1 hanger layout a. a clear design of hanger should be installed strictly in accordance with the drawings and designs shall not be installed wrong, missing, etc. B. own arrangement of piping support and hanger set and selection should be based on comprehensive analysis of general layout of piping systems; cold installation of steam pipe with particular attention reserved for compensation of thermal expansion displacement and orientation. C. support systems should be rational to withstand pipe loads, static load and incidental load; reasonable piping displacement; guaranteed under various conditions, stress are within the allowed range. Strength, stiffness, and meet requirements to prevent vibration and soothing water, without affecting the adjacent equipment maintenance and other piping installation and expansion. D. equipment connected to the interface to meet pipeline thrust (torque) limit requirements; increase the stability of piping systems to prevent pipeline ... Tube wall thickness (mm) 2-3 4-6 7-10 weld form no slope mouth weld strengthening height h (mm) 1-1.5 1.5-2 weld width b (mm) 5-6 7-6 has slope mouth weld strengthening height h (mm) 1.5-2 2 weld width b (mm) cover had each edge slope mouth about 2 mm argon arc welding weld strengthening surface height and width tube wall thickness (mm) 2--3 3--4 5--6 weld form weld strengthening height h (mm) 1-1 .5 1.5-2 2-2.5 width b (mm) (4)耳鼻喉、口腔感染:急慢性中耳炎、牙周炎、鼻炎; (5)骨关节感染:骨髓炎; (6)其他感染:心血管感染、皮肤、软组织感染。 3.广谱青霉素类 氨苄西林 (ampicillin)、 匹氨西林(pivampicillin) 阿莫西林 (amoxycillin) 特点: 耐酸，可口服 不耐酶，对耐药金葡菌感染无效 对G-杆菌有效，可用于伤寒、副伤寒、百日咳、大肠埃希菌、痢疾志贺菌等G-杆菌所致的呼吸道感染、尿路感染。 常见广谱青霉素类药物: 阿莫西林克拉维酸钾片和注射剂 注射用派拉西林钠舒巴坦钠 阿莫西林胶囊 注射用美洛西林钠 下面就以阿莫西林克拉维酸钾片的具体特点进行说明: 克拉维酸为β-内酰胺酶抑制剂， 本身只有微弱的抗菌活性，但具 有强大的广谱β内酰胺酶抑制作 用，两者合用，可保护阿莫西林 and performance test copies of the record. If necessary, review should be carried out; 4) for spring hangers (included simple spring, hangers and constant support hangers) it should also be recognized as setting and locking of loads. 5) check the surface quality, folded layering and without cracks, rust and other defects. 5) after completion of the test and control drawing number one by one, by series baled. Color alloy steel parts, the parts marking installation location and rotation about the direction you want. 7.3.14. hangers installation 7.3.14.1 hanger layout a. a clear design of hanger should be installed strictly in accordance with the drawings and designs shall not be installed wrong, missing, etc. B. own arrangement of piping support and hanger set and selection should be based on comprehensive analysis of general layout of piping systems; cold installation of steam pipe with particular attention reserved for compensation of thermal expansion displacement and orientation. C. support systems should be rational to withstand pipe loads, static load and incidental load; reasonable piping displacement; guaranteed under various conditions, stress are within the allowed range. Strength, stiffness, and meet requirements to prevent vibration and soothing water, without affecting the adjacent equipment maintenance and other piping installation and expansion. D. equipment connected to the interface to meet pipeline thrust (torque) limit requirements; increase the stability of piping systems to prevent pipeline ... Tube wall thickness (mm) 2-3 4-6 7-10 weld form no slope mouth weld strengthening height h (mm) 1-1.5 1.5-2 weld width b (mm) 5-6 7-6 has slope mouth weld strengthening height h (mm) 1.5-2 2 weld width b (mm) cover had each edge slope mouth about 2 mm argon arc welding weld strengthening surface height and width tube wall thickness (mm) 2--3 3--4 5--6 weld form weld strengthening height h (mm) 1-1 .5 1.5-2 2-2.5 width b (mm) 免遭β内酰胺酶水解，产生协同 抗菌作用，增强了抗菌活性和扩 大了抗菌谱。 药理特点: 本类药物对革兰阳性菌作用与青霉素相仿，对部分革兰阴性杆菌亦具有抗菌活性，如流感嗜血杆菌、大肠埃希菌、奇异变形杆菌。 临床应用: 适用于敏感菌所致的呼吸道感染、尿路感染、皮肤软组织感染、脑膜炎、败血症以及心内膜炎等。 青霉素类临床应用注意事项: , 无论采取何种给药途径，用青霉素类药物给药前必须详细 询问患者有无青霉素类过敏史及过敏性疾病，并且须先做 青霉素皮试 , 过敏性休克一旦发生，必须就地抢救 , 不用于鞘内注射 , 青霉素钾盐不可快速静注 , 在碱性溶液中易失活 五、不良反应 1. 过敏反应 — 主要不良反应 :皮肤过敏、血清病样反应较多见;过敏性休克:最严重，表现有循环衰竭、呼吸衰竭and performance test copies of the record. If necessary, review should be carried out; 4) for spring hangers (included simple spring, hangers and constant support hangers) it should also be recognized as setting and locking of loads. 5) check the surface quality, folded layering and without cracks, rust and other defects. 5) after completion of the test and control drawing number one by one, by series baled. Color alloy steel parts, the parts marking installation location and rotation about the direction you want. 7.3.14. hangers installation 7.3.14.1 hanger layout a. a clear design of hanger should be installed strictly in accordance with the drawings and designs shall not be installed wrong, missing, etc. B. own arrangement of piping support and hanger set and selection should be based on comprehensive analysis of general layout of piping systems; cold installation of steam pipe with particular attention reserved for compensation of thermal expansion displacement and orientation. C. support systems should be rational to withstand pipe loads, static load and incidental load; reasonable piping displacement; guaranteed under various conditions, stress are within the allowed range. Strength, stiffness, and meet requirements to prevent vibration and soothing water, without affecting the adjacent equipment maintenance and other piping installation and expansion. D. equipment connected to the interface to meet pipeline thrust (torque) limit requirements; increase the stability of piping systems to prevent pipeline ... Tube wall thickness (mm) 2-3 4-6 7-10 weld form no slope mouth weld strengthening height h (mm) 1-1.5 1.5-2 weld width b (mm) 5-6 7-6 has slope mouth weld strengthening height h (mm) 1.5-2 2 weld width b (mm) cover had each edge slope mouth about 2 mm argon arc welding weld strengthening surface height and width tube wall thickness (mm) 2--3 3--4 5--6 weld form weld strengthening height h (mm) 1-1 .5 1.5-2 2-2.5 width b (mm) 和中枢抑制。 2. 局部刺激症状:红肿、疼痛、硬结; 3. 大剂量可引起精神错乱、抽搐;高血钾症或高钠血症。 4. 赫氏反应 用青霉素治疗梅毒或钩端螺旋体时，出现症状加剧的现象。 预防措施: 1(询问过敏史; 2(皮试; 3(注射后观察30 min; 4(准备抢救药品及器材。 青霉素的缺点: , 对酸性水溶液不稳定，只能注射给药，不能口服。 , 对碱性水溶液不稳定(成盐反应须十分小心进行)，须做 成粉针剂。 , 抗菌谱较窄，对革兰阴性菌的疗效差。 , 在使用过程中，细菌易产生耐药性。 , 有严重的过敏性反应(休克)。 为了克服青霉素的诸多缺点，自20世纪50年代开始，人们对青霉素进行结构修饰。成功地解决了青霉素的不耐酸、不耐酶和抗菌谱窄的问题，在口服、广谱、耐酶等半合成青霉素研究上取得重大进展。 六、青霉素使用现状 and performance test copies of the record. If necessary, review should be carried out; 4) for spring hangers (included simple spring, hangers and constant support hangers) it should also be recognized as setting and locking of loads. 5) check the surface quality, folded layering and without cracks, rust and other defects. 5) after completion of the test and control drawing number one by one, by series baled. Color alloy steel parts, the parts marking installation location and rotation about the direction you want. 7.3.14. hangers installation 7.3.14.1 hanger layout a. a clear design of hanger should be installed strictly in accordance with the drawings and designs shall not be installed wrong, missing, etc. B. own arrangement of piping support and hanger set and selection should be based on comprehensive analysis of general layout of piping systems; cold installation of steam pipe with particular attention reserved for compensation of thermal expansion displacement and orientation. C. support systems should be rational to withstand pipe loads, static load and incidental load; reasonable piping displacement; guaranteed under various conditions, stress are within the allowed range. Strength, stiffness, and meet requirements to prevent vibration and soothing water, without affecting the adjacent equipment maintenance and other piping installation and expansion. D. equipment connected to the interface to meet pipeline thrust (torque) limit requirements; increase the stability of piping systems to prevent pipeline ... Tube wall thickness (mm) 2-3 4-6 7-10 weld form no slope mouth weld strengthening height h (mm) 1-1.5 1.5-2 weld width b (mm) 5-6 7-6 has slope mouth weld strengthening height h (mm) 1.5-2 2 weld width b (mm) cover had each edge slope mouth about 2 mm argon arc welding weld strengthening surface height and width tube wall thickness (mm) 2--3 3--4 5--6 weld form weld strengthening height h (mm) 1-1 .5 1.5-2 2-2.5 width b (mm) 就一些医院门诊药房看来，青霉素的使用已是大大减少了，普通感冒发烧动不动就是头孢二、三代，而且青霉素在医院门诊药房的种类和数量也是少之又少了,可见抗生素的滥用在一定的程度上得到了缓解。 原因分析: , 抗生素的滥用，使大部分细菌都有青霉素耐药性，临床应 用抗生素效果大不如从前,病人都希望病情快点好转，认 为越是新的、贵的抗生素疗效越好。 , 青霉素很便宜，没什么利润，在以药养医的背景下,它给 医院及医生带不来经济利润,无法服务于养医的经营方 向。 , 青霉素容易过敏。 给青霉素活路,就是给我们生路 如果再无休止地滥用抗生素，人类将面临无药可治的地步，青霉素就是一个活生生的例子，抗生素滥用会使机体的病菌产生耐药性，慢慢对这种药物不再敏感;另一方面，病菌不断发生变异，催生越来越多的“超级细菌”，最终面临“无药可医”。 and performance test copies of the record. If necessary, review should be carried out; 4) for spring hangers (included simple spring, hangers and constant support hangers) it should also be recognized as setting and locking of loads. 5) check the surface quality, folded layering and without cracks, rust and other defects. 5) after completion of the test and control drawing number one by one, by series baled. Color alloy steel parts, the parts marking installation location and rotation about the direction you want. 7.3.14. hangers installation 7.3.14.1 hanger layout a. a clear design of hanger should be installed strictly in accordance with the drawings and designs shall not be installed wrong, missing, etc. B. own arrangement of piping support and hanger set and selection should be based on comprehensive analysis of general layout of piping systems; cold installation of steam pipe with particular attention reserved for compensation of thermal expansion displacement and orientation. C. support systems should be rational to withstand pipe loads, static load and incidental load; reasonable piping displacement; guaranteed under various conditions, stress are within the allowed range. Strength, stiffness, and meet requirements to prevent vibration and soothing water, without affecting the adjacent equipment maintenance and other piping installation and expansion. D. equipment connected to the interface to meet pipeline thrust (torque) limit requirements; increase the stability of piping systems to prevent pipeline ... Tube wall thickness (mm) 2-3 4-6 7-10 weld form no slope mouth weld strengthening height h (mm) 1-1.5 1.5-2 weld width b (mm) 5-6 7-6 has slope mouth weld strengthening height h (mm) 1.5-2 2 weld width b (mm) cover had each edge slope mouth about 2 mm argon arc welding weld strengthening surface height and width tube wall thickness (mm) 2--3 3--4 5--6 weld form weld strengthening height h (mm) 1-1 .5 1.5-2 2-2.5 width b (mm)