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投标翻译样文 添加时间:2019-1-29



General Provisions


1. The pipes shall meet following conditions before being installed:


a. The construction drawing and other technical documents are complete, and the technical disclosure of drawings has been completed and meets the construction requirements;


b. The construction scheme, construction technique and the supply of materials and machines and tools shall be able to guarantee the normal construction;


c. The construction personnel shall have completed the technical training for the installation of polypropylene pipeline for building water supply. 


2. The pipes and pipe fittings provided shall meet the design specifications, and shall come with product instructions and quality certificate.


3. Materials having any sign of damage shall not be used. If any abnormal quality condition is found on the pipes, a technical appraisal or re-inspection shall be completed before use.


4. All openings shall be blocked off during the installation of the pipeline system.


5. The pressure rating of cold and hot water pipes and their usage occasions shall be re-checked before the installation. The markers of pipeline shall face the outside and is placed in conspicuous position.


II. Key Points for the Installation and Laying of Pipeline


1. For concealed lying of pipe in wall, it is suitable to reserve grooves in coordination with the civil construction. If there is no specific provision on the dimension, the wall groove for concealed pipes shall have a depth at De20mm  and width at De4060mm. The groove surface must be smooth without any sharp corner and other projection. After the pipeline passes the pressure testing, the wall groove shall use M7. Grade 5 concrete mortar shall be used for filling and sealing.


2. If the pipes are buried in the floor surface layer, the concealed lying shall be constructed in accordance with the location on the design drawing. A graphical record shall be available if any change is made in the site construction.

3、管道安装时,不得有轴向扭曲,穿墙或楼板时,不宜强制校正。给水聚丙烯管与其它金属管道平行敷设时应有一定的保护距离,净距离下宜小于 100mm,且聚丙烯管宜安装在金属管道的内侧。

3. The pipe installation shall not have any axial distortion, and the pipe should not be corrected forcibly when passing through wall or floor slab. Where the water supply polypropylene pipe is laid parallel to other metal pipes, there shall be certain protection distance between them, wherein the net distance should be less than 100mm and the polypropylene pipe should be installed on the inner side of metal pipe.


4. The indoor exposed pipes should be installed after the whitewash of civil construction. Before the installation, holes and casing pipes shall be reserved and embedded correctly in coordination with the civil construction.

5、管道穿越楼板时,应设置钢套管,套管高出地面 50mm,并有防水措施。管道穿越屋面时,应采取严格的防水措施。穿越前端应设固定支架。

5. To pass through the floor slab, the pipes shall be equipped with steel sleeve, and the steel pipe shall be 50mm higher than the ground and shall have waterproofing measure. To pass through the roof, the pipes shall have strict waterproof measure. A fixed support shall be set at the front end of the section passing through.


6. Where the hot water pipes pass through the wall, the steel sleeve shall be set in coordination with the civil construction. Where the cold water pipes pass through the wall, the holes may be reserved wherein the dimension of the opening shall be 50mm greater than the outer diameter.


7. Before the pipes directly buried in the floor surface layer and in the wall body are sealed, the acceptance record for pressure test and concealed work shall be completed.


8. The laying of building’s buried inlet pipes and indoor buried pipes are required as below:


a.  The laying of pipes 0.00 under the indoor floor should be constructed in two stages. The pipes 0.00 under the indoor floor to the outer wall section of the foundation wall shall be laid first; after the civil construction is completed, the outdoor connecting pipes shall be laid;


b.  The pipes below the indoor floor shall be laid by re-excavation after the backfill and compaction for the civil construction is completed. It is strictly prohibited to lay pipes before backfilling or in the soil layer not compacted yet;


c.  The bottom of trench for pipe laying shall be smooth without any sharp or hard protruding object. The particle diameter of soil should be no greater than 12mm, and a sand bed in 100mm thick shall be laid where necessary.


d.  In the backfill for buried pipeline, the backfill soil around the pipes shall have no sharp or hard object which directly contacts with the pipe wall. Sandy soil or soil with a particle size no greater than 12mm shall be used to backfill to 300mrn above the pipe top and shall be compacted before the original soil is backfilled. The buried depth of the indoor buried pipes should be no lower than 300mm;


e.  Protective pipe shall be set at the position where the pipe goes out of the floor, and shall be 100mm higher than the floor;


f.  Where the pipes pass through the foundation wall, metal sleeve shall be set. If the design has no requirement, the free height above the reserved hole for the casing pipe and foundation wall shall be no lower than 100mm;


g.  Where the pipeline passes through the road and the thickness of covering soil is lower than 700mm, strict protective measure shall be taken.


III. Key Points for Pipe Connection


1. The water supply polypropylene pipe and pipe fittings in same material shall be installed through hot melt connection by dedicated hot melt tools. Pipes concealed in wall body or floor shall not be connected through screwed or flange connection.


2. For the connection between water supply polypropylene pipe and metal pipe fittings, the polypropylene pipe fittings having metal fittings shall be adopted for the transition. Such pipe fittings shall be connected with plastic pipe through hot melt connection, and shall be connected with metal fittings or sanitary hardware fittings through screwed connection.


3. The hot melt connection shall be carried out as per following steps:


a.  The operation is not allowed until the hot-melt machine is powered on and the indicator light for reaching the operating temperature is on;


b.  The pipe must be cut to make the end surface vertical to the pipe axis. Generally, the pipes shall be cut by pipe scissor or pipe cutter. Where necessary, sharp hacksaw may be used, but the sharp edge and burr on the pipe section shall be removed after cutting.


c.  The connecting end surface between pipe and pipe fitting must be clean and dry without any oil;


d.  For the hot melt connection of bend or tee joint, it shall accord with the requirements of design drawing and pay attention to its direction. And it shall mark the position by auxiliary signs on the straight direction of the pipe fittings and pipe;


e.  Lead the pipe end into the heating sleeve without rotating the pipe, and insert the pipe end into the marked depth. Meanwhile, push the pipe fitting onto the heating head without rotating the pipe, and reach the specified marked position.


f.  Immediately after the heating time is out, simultaneously take down the pipe and pipe fitting from the heating sleeve and heating head, and rapidly insert the pipe into the marked depth uniformly in a straight line without rotating the pipe, and make the junction form a uniform flange;


4. The electrofusion connection for pipeline shall meet following provisions:


a.  The fused part of the electrofusion pipe fittings and pipes should be kept free from moisture;


b. The connection end of the electrofusion socket connecting pipe shall be cut vertically; the clean cotton cloth shall be applied to clean the dirt on the connection surface of the pipe and pipe fittings; the insertion depth shall be marked; the coat of the pipe shall be scraped off;


c. Straighten the two opposite connecting fittings and make them on one same axis;


d. The wire connection between electrofusion connecting machine and the electrical fused fitting shall be correct. Before the connection, it shall inspect the voltage of ohmic heating, wherein the heating time shall accord with the related provisions from the manufacturer of the electrofusion connecting machine and the electrical fusion pipe fittings;


e.  In the process of fusion and cooling, do not move or turn the electrofusion pipe fittings and the fused pipe, and do not apply any pressure on the connecting fitting;


f.  The standard heating time for electrofusion connection shall be provided by the manufacture, and shall be adjusted according to different ambient temperature. If the electrofusion machine has the temperature self-compensating function, the heating time will not need to be adjusted.

Steel-plastic Composite Pipe


(I) Construction Technology of Steel-plastic Composite Pipe 


1) Technology principle: The inner rib embedded lining plastic steel pipe is machined from welded steel pipe with convex reticulated pattern on its inner wall and polypropylene plastic pipe through hole shrinkage treatment, which forms interference fit between the steel pipe and plastic pipe. The inner rib of the steel pipe is embedded in the outer wall of the plastic pipe, so as to form the composite of steel and plastics. In the construction of inner rib embedded lining plastic steel pipes, based on the cold extruding principle, a special-purpose channeling machine is applied to make extension and deformation on certain distance away from the end surface of the pipe so as to form a small arc groove, and then a clamp-spring stainless snap ring is placed in the groove, and the nut or connector, new-type enamel pipe fitting and its accessories are set on the pipe and fastened. The installation method is quick and convenient. Because of the cone self-locking design on the matching part of the snap ring, as well as the bidirectional sealing design on both end direction and radial direction, the pipe has a reliable connecting strength and anti-leaking performance.


(II) Technological Process 


1) Prepare the construction.


① Before the pipeline construction, carefully inspect whether the elevation, position and dimension of the reserved holes, reserved casing pipes and embedded parts on the walls, floor slabs and other structures where pipes will pass through are correct.


② Prepare the cooperation measures and schemes with the secondary decoration and other specialties during the pipeline construction.


③ Carefully inspect the appearance of the pipes and pipe fittings, and clear the dirt and impurities in and on the pipes and pipe fittings. 


2) Draw the field construction drawing. Before the pipeline construction, the technical personnel shall draw the detailed pipeline construction drawing according to the design drawing, the requirements from the construction side and the coordination with other specialties. Actually measure the installation length of the pipeline and the installation position of pipe fittings, for easier pipeline maintenance and construction. As the lining plastic steel pipe uses modified polypropylene (PP) as the lining material, and uses baking varnished and galvanized steel pipe as the outer pipe, it shall also take pipe’s heat insulation and the corresponding protective measures under different ambient temperatures into consideration.


3) Process the pipes and pipe fittings.


① Fix the special-purpose channeling machine on the operation platform for easier pipe processing.


② Do piping in accordance with the field construction drawing and pre-assemble the pipeline.


③ Cut off and groove the pipes. 

管材切断时,根据现场测量所需实际长度定尺。用内筋嵌入式衬塑钢管滚槽机断管,保证断口端面与管材轴线垂直,切斜度DN50以下管材不大于2度,DN65以上管材不大于1.5度,并去掉毛刺、飞边。 压槽和切断时,应依据管道直径大小选择进刀速度。进刀不能太快,滚槽机手柄每轮近给量不大于0.2mm。如果进刀太快,可能导致个别管材出现变形和破裂。 

In the pipe cutting, it shall measure the specified length according to the field requirement. It shall cut the pipe by channeling machine for inner rib embedded lining plastic steel pipe, and ensure the fracture end surface is vertical to the pipe’s axis. The cutting slope shall be no greater than 2 degrees for pipes below DN50, and no greater than 1.5 degrees for pipes above DN65. Remove the burr and flash. In the groove rolling and cutting off, the feeding speed shall be selected according to the pipe diameter. The feeding shall not be too fast, and the feed amount of the channeling machine’s hand shank in each round shall be no greater than 0.2mm. Too fast feeding may cause deformation or fracture on some of the pipes. 


4) Fabricate and install the support.


① It is strictly prohibited to adopt gas cutting welding for the material cutting and eyelet blowing in the support fabrication. The holding clamp of support and hanging bracket shall be fabricated to tightly contact with the pipe. The corrosion prevention of support and hanging bracket shall be uniform without any paint flowing.


② For supports and hanging brackets which are set on wall, column and beam, it shall embed them or reserve holes during the civil construction, and it is prohibited to punch or embed without permission for fear of damaging the building or the waterproof layer. If any condition forces to do so, the consent from related department shall be obtained, and where the condition allows, it shall try best to adopt the expansion bolt or fastener for fixing.


③ To fix a support by expansion bolt, it shall drill holes on the wall as per the position of the bolt holes of the support, wherein the hole diameter shall be equal to the outer diameter of the expansion set, and the hole depth shall be equal to the bolt length. Then, insert the expansion bolt into the bolt hole of the support and drive it into the wall hole, and then tighten the nut by spanner. 


5) Lay the pipes.


① The coating layer on the connecting part of pipes shall be removed before pipe installation;


② Inspect where all the accessories of the pipe connector are complete;


③ For pipe fittings for DN50 and below, install the nut, washer, and sealing ring on the pipe in the sequence shown on the diagram attached to the instructions for pipe fitting assembly, and then inset the pipe into the socket of the pipe, and lastly tighten the nut by spanner.


④ For the connection of large pipe fittings above DN50, nest the connector, snap ring, washer, and sealing ring on the pipe, then connect with the connector ring flange, and tighten the bolts. Tighten the corner in the mean time of tightening the bolts of ring flange for fear of any bad sealing caused by deflection.


⑤ When laying the indoor pipeline, the distance from the pipe to wall surface shall be 12~15mm. Steel sleeve shall be set where the pipe passes through the floor slab, and it shall 50~100mm above the floor. In the installation of main pipes, no subsiding and hunch-up wave phenomenon or left and right distortion phenomenon is allowed. No threading is allowed on the lining plastic steel pipe. The horizontal pipe of the pipeline system shall have a gradient at 2~5‰ towards the drainage opening.


⑥ The buried lining plastic steel pipes and pipe fittings shall have antiseptic treatment by surface painting or pitching. But the indoor concealed pipes and fittings may be buried in the floor slab directly, and the wall groove where pipes are buried shall be filled up by 1:2 concrete mortar. Pipes under the indoor floor shall be laid in the soil layer compacted by civil construction. The trench bottom shall be smooth, and a sand bed in 100mm thick may be laid where necessary.


⑦ When the buried pipeline is backfilled, it shall firstly use sand and stone or soil with particle size no more than 12mm to 300mm to backfill to the place above the pipe roof, and then use the original soil to backfill after compaction.


⑧ In the pipe laying, it shall consider the expansion length change caused by temperature difference, and take corresponding expansion compensating measure according to the actual calculation. 


6) Test the water pressure of pipes. The pressure test for lining plastic steel pipe is same as that of general galvanized steel pipes.


7) Quality control.


① Set up the quality leading team, and establish QC team.


② For pipeline laid on roof and exposed outdoor place, asbestos rubber shall be adopted for heat insulation. Before accessing water, the coating layer shall be well protected for fear of electrochemical reaction erosion caused by direct contact between the lining plastic steel pipe and wet object.


③ Steel angle reinforcement measure shall be adopted at the joint between the pipe and the hydrant.


④ Where pipes are laid parallel to other pipelines in same trench (frame), the pipe shall be laid along the trench (frame) edge. Where pipes are laid in vertical parallel, the pipes shall be laid below the hot water and steam pipe. Where pipes are laid across other pipeline, the protective measure of rubber isolation shall be adopted.


⑤ In the pipe grooving, the ideal groove spacing shall leave no gap after the snap ring, washer and sealing ring are assembled. To reach the ideal groove spacing, the installation personnel shall use vernier caliper to measure the groove spacing, so as to guarantee the installation quality of the pipeline.

Metal Hose


Metal hose can bend at will, and generates very low stress by being bended under the condition of rated bending radius. Therefore, it can bring great convenience to the installation work, and also plays certain role in guaranteeing the safe operation of the pipeline system. This is the main reason why certain pipeline systems must use the metal hose.


But in complicated pipeline system, various difficulties often appear in the installation work due to the limitation of space position and condition: the formed pipe cannot be installed; the pipe has to bend and come straight; pipes installed constrainedly will inevitably cause local cold straightening. According to the pipe size and the actual site conditions, the cold straightening amount ranges from several millimeters to tens of millimeters, even up to hundreds of millimeters. Practice shows that, the larger such amount is, the higher its internal stress will be. The residual installation stress in the pipeline system is undoubtedly a great hidden danger, which will cause the occurrence of metal hose fracture and other problems, affecting the pipeline safety. 


The lower installation stress the metal hose has, the easier the installation work will be. And it will also play a great role in ensuring the safety of pipeline. In the process of installing the stainless steel metal hose, the installation stress can be controlled well. 


Five-step welding method for metal hose


Where the metal hose is used as the highly flexible pipe for connecting metal equipment, it is generally connected with other equipments by welding method. In the process of welding, we often use the five-step welding method.


Step I: Pipe orifice size. Before welding, measure the pipe length fist, and then cut the pipe by pipe cutter. 


Step I: Pipe cleaning. As the pipe is metallic, some waste residues may be generated inside the pipe due to oxidation which will impact the welding effect. Therefore, before welding, we should use abrasive cloth or paper to grind off the waste residues in pipes. 


Step III: Clean the accessories by pipe brush. The accessory cleaning will guarantee the junction between welded hose and tin.


Step IV: Master the welding time. Generally, the corresponding length of welding material depends on the length of welded pipe required.


Step V: Use torch to heat the hose. Using torch to heat the hose is to guarantee the uniform heating on the welded point of pipe. Note that, in the application of torch, it shall guarantee the flame is close to the extent of covering the whole pipe diameter.


Mastering the welding steps for metal hose is beneficial to a safer metal hose welding by the user. The welding of metal hose is not easy, but this work will be completed better as long as user carefully studies the related knowledge and operates rigorously and carefully.


How to eliminate the distortion of metal hose


In the process of installation, the metal hose will be stretched and distorted due to improper installation or excessively high pressure on the hose. A higher stress generated by the stretching or distortion than the ultimate strength of the steel wire net cover will cause a greater damage.


The frequently-used method is the application of a rigid elbow connector to eliminate the distortion and obtain a satisfactory bending state.


1. Use a rolling wheel equivalent to the bending radius to eliminate the extreme bending of stainless steel metal hose.


2. Use a shifting rolling wheel equivalent to the bending radius to eliminate deflection and distortion caused by the interlacing of stainless steel metal hoses.