管道及阀件的安装 Installation of pipes and valves
（1）
管道安装的基本要求 Basic requirements
A、A.
管道安装的基本原则：先大管，后小管；先主管，后支管。 The fundamental of pipe installation: big pipe first, small pipe second; main pipe first, branch pipe second.
B、B.
电弧焊连接的管道在放样划线的基础上按矫正管材、切割下料、坡口、组对、焊接、清理焊渣等工序进行施工。 The construction process of pipes connected by arc welding: rectify pipes, incise material, bevelling, assembly, welding and clear welding slag.
C、C.
螺纹连接的管道按矫正管材、切割下料、套丝、连接、清理填料等工序进行施工。 The construction process of screwing pipes: rectify conduicts, incise material, threading, connection and clear padding.
D、D、
空调冷水管安装时应有不小于1.0‰的坡度，热水管应有不小于2.5‰的坡度，并在系统的最低点处配置DN25泄水管及相同管径的阀门，泄水管引至附近厕所水池或空调机房内的地漏，在系统的最高点处设置DN20 ZP-1型自动排气阀。 The cold water pipe of air conditioning shall has a gradient no less than 1.0‰, the gradient of hot-water pipe shall no less than 2.5‰, install DN25 discharge pipe and the valves with the same caliber in the minimum point of system, the discharge pipe shall be stretched to the neighboring toilet basin or floor drain in air conditioning room, install DN20 ZP-1 automatic exhaust steam valve in the peak point of system.

华译网北京翻译公司翻译过大量有关管道及阀件的安装的文件资料,Beijing Chinese Translation Service Company has translated many technical documents about Installation of pipes and valves
（2）
管道安装方法 Method of installation
无缝钢管及焊接钢管的焊接施工工序如下： The welding procedures of seamless steel pipe and welded steel pipe are as follows:

按图下料Baiting according to the figure
坡口加工 Bevelling of the edge
坡口及其内外侧清理 Clear of the groove, the inside and outside
焊缝外观检查 Inspection of weld appearance
焊接 Welding
坡口组对Groove assembly

①
坡口加工及清理：管道的切割坡口一般采用氧-乙炔焰气割，气割完成后，用锉刀清除干净管口氧化铁，用磨光机将影响焊接质量的凹凸不平处削磨平整。 Bevelling of the edge and clearance：incise the groove by oxy-acetylene flame cutting; after gas cutting, clear ferric oxide around pipe orifice by file, polish the roughness which will have effect on welding quality by polishing machine.小直径管道尽量采用砂轮切割机和手提式电动切管机进行切割，然后用磨光机进行管口坡口。 Small diameter pipes shall be incised by abrasive wheel cutting machine and portable electric pipe cutter, then bevel pipe orifice by polishing machine.管道坡口采用V型坡口，坡口用机械加工或砂轮机打磨，做到光滑、平整。 Groove adopts v-groove and polished by mechanical processing or rotary sander to make it smooth and level.对坡口两侧20mm范围内将油污，铁锈和水份去除，且保证露出金属光泽，保证坡口表面不得有裂纹、夹层等缺陷，并清除坡口内外侧污物。 Clear the oily soil，rust and moisture around 20mm in the both sides of groove; ensure the exposed metallic lustre, groove face without crack and interlayer, clear contamination inside and outside of groove.焊接坡口形式如下图。 The shape of welding groove has been shown as follows.
②
焊条、焊剂使用前应按说明书进行烘干，并在使用过程中保持干燥。 Welding rod and soldering flux shall be oven dry according to specification before usage and keep dry in service.焊条药皮无脱落和显著裂纹。 Electrode coating shall be no desquamation and visible crackle.
③
焊前管口组对：管口组对采用专用的组对工具，以确保管子的平直度和对口平齐度。 Pipe orifice assembly before welding: pipe orifice assembly adopts special instrument to ensure the flatness of pipe and contra-aperture.管道对接焊口的组对必须做到内壁齐平，特别是浆料不锈钢输送管道，内壁错边量绝对不可超标；管子组对点固，应由焊接同一管子的焊工进行，点固用的焊条或焊丝应与正式焊接所用的相同，点焊长度为10～15mm，高度为2～4mm，且应超过管壁厚的2/3；管道焊缝表面不得裂缝、气孔、夹渣等缺陷；管子、管件组对点固时，应保持焊接区域不受恶力环境条件（风、雨）的影响； The assembly of butt welding junction of pipe should be flush with the inner wall; especially for the stainless steel running piping of pulp, the unfitness of butt joint absolutely must not overproof; Pipe assembly fixed by point by the same welder who welded the pipe, the welding rod and welding wire also shall be the same with the formal welding， the spot welding length is 10～15mm, the height is 2～4mm and not exceed 2/3 of the pipe thickness;The weld surface of pipe shall have not flaws such as crack, pore, slag inclusion; during the course of point fixing of pipe assembly, the weld zone shall be prevent form the bad ambient condition (wind, rain);
④
管道焊接： Pipe welding:
焊接施工必须严格按焊接作业指导书的规定进行；焊接设备使用前必须进行安全性能与使用性能试验，不合格设备严禁进入施工现场；焊接过程中做好自检与互检工作，做好焊接质量的过程控制。 Welding procedure must satisfy the guide book for welding; welding equipments shall be tested the safety feature and usability，disqualification equipments are strictly prohibit to use in job location; During the welding process, self-checking, cross-check process control of welding quality shall be carried out.
管道焊接采用手工电弧焊，焊条在使用前放入焊条烘干箱在100℃～150℃的温度下烘焙1～2小时，并且保证焊条表面无油污等。 Pipe welding adopts manual electric arc welding, welding rod shall be oven dried in 100℃～150℃ 1～2 hours to ensure the surface without oily soil before welding.焊接中注意引弧和收弧质量，收弧处确保弧坑填满，防止弧坑火口裂纹，多层焊做到层间接头错开。 Pay attention to the quality of generating the arc and drawing the arc in welding, drawing the arc to ensure the arc pit be filled up, crater crack shall be avoided, interlaminar joints of making overlapping run shall be staggered.每条焊缝尽可能做到一次焊完，因故被迫中断时，及时采取防裂措施，确认无裂纹后方可继续施焊。 Each weld shall be welded at once as much as possible, if it was interrupted, adopt crack control measures in time, validate there was flawless and then keep on welding.
管道连接时，不得强力对口，尤其与设备连接部分当松开螺栓时，对口部分应处于正确的位置。 The contra-aperture of pipe mustn't be connected by brute force, especially the bolt of device attachment is unbolted, the contra-aperture shall be in the correct position.
管道上的对接焊口或法兰接口必须避免与支、吊架重合。 Butt welding joint and flange connecting piece shall be avoided matching together with branch and hanger frame.水平管段上的阀件，手轮应朝上安装，只有在特殊情况下，不能朝上安装时，方可朝下或朝侧面安装。 The handwheels of valves in horizontal pipe shall be installed open upward, only in particular cases, handwheels can be installed open downward or sideward.管道上的仪表取源部件的开孔和焊接应在管道安装前进行。 Pore opening and welding of source components shall be carried out before pipe installation.
焊缝表面的焊渣必须清理干净，进行外观质量检查，看是否有气孔、裂纹、夹杂等焊接缺陷。 The welding slag on weld surface must be cleared, inspect the appearance quality to ascertain whether there are welding defects such as pore, crackle and impurity如存在缺陷必须及时进行返修，并作好返修记录。 If there was any flaw, repair it in time and make repair record.