电气工程电缆敷设工艺(英文版).doc

Content1. Foreword.32. Preparation before laying out cables.353. Principal requirements of laying out cables564. Drawing cables.675. Fixing cables.76. Laying out cables in the metal duct.77. Laying out cables in the refrigeration area78. Laying out cables near the radio electric equipments789. Checking items.81. Foreword1.1 This workmanship is based on the GL rule 2000, IEC standard No.92-401 publication, relative rule in the workmanship for laying out the marine cables of the professional standard of the Peoples Republic of China and the specification of the ship, combinated the traditional workmanship and the practicality of our shipyard.1.2 The following problems in laying out cables are stated in other documents about workmanship:a. Cables grounding workmanship is shown in the grounding workmanship for electric equipments. b. Processing cables end is shown in the installing workmanship for electric equipments. c. Sealing cables is shown in the sealing workmanship for marine cables. (QB/LRA32008-91)d. The laying out cables workmanship with special requests is not included in the document.2. Preparation before laying out cables2.1 Prepare the following relative working drawings and technical documents:a. The workmanship of laying out cablesb. The workmanship of sealing cablesc. The workmanship of electric equipments groundingd. The combination electric lofting drawing e. The arrangement drawing for electric equipmentf. The first electric system drawing, the second electric system drawingg. The cable of main way tending towards drawingh. The cables list book and the drawing cables booki. Other drawings and technical documents about laying out cables2.2 According to the above working drawings and documents, prepare all kinds of fabricated sections, fixtures and necessary tools for laying out cables. It is better to arrange the fixtures and fabricated sections according to the working area, and to place them separately.2.3 For conveniently installation on board, the fixtures of cables shall be made as assembling parts in the workshop. The assembling parts are shown in table No.1.The bracket of assembling parts shall be enough strong. The distance between the feet of assembling parts is usually not more than 1500mm.1supporting angle bar 2I type bracket 3bracket angle bar2.4 According to the cables list and cables laying out book, cut cables for preparing, try best to earlier cut the cable laid out later, later cut the cable laid out earlier. Coil cables on the cables drum in turn according to the sequence of laying out. 2.5 Make the temporary mark of cables in advance. On the mark shall state the number of cables, size, length, the ending equipments and position. It is proper to dividually make at least two marks on two ends of every cable. The temporary marks may be made of the white rubberized fabric. When cutting every cable, tie the temporary mark on the two ends of cable.2.6 If there are some cables through stop opinion of cofferdam or deck, shall make the striking marker “stop opinion” with different color painting.2.7 The cutting section of cable shall avoid damp to affect insulation, when it necessary properly close it.2.8 According to the lofting drawing for cables and the size of fixture and fitter confected in advance, to execute location on board, draw the welding position of fitter and fixture and the opening position and dimension of cable bracket, cable penetration, stuffer box.2.9 Make holes on the structure and deck.2.9.1 The opening usual shall be round or kidney shaped, if the opening is other shape, at less it shall be round corner. The size of hole shall comply with cable frames, cable canisters, stuffer box, and not proper to be too big.2.9.2 Make hole on the deck stringers, webs, showing in the table No.2. a. The highness of opening (h) shall be not over 25% of the highness of stringers and webs, the width of opening (I) shall be not over 60% of the distance of frames (L) or shall be complemented intension; the distance from the edge of opening to the stringer panel shall be not less than 40% of the highness of stringer web (B).b. Openings shall be scattered, can not be concentrated in the distance between longitudinal frame or distance between frames at same time, when it is need to make two or more holes, shall arrange along the horizon, the sum of all width of holes shall be not over half of the distance between frames or longitudinal frames.If the opening is not complied with the above, it shall be complemented intension.2.9.3 Make holes on the surface of decka. The shape of opening shall be rotundity, kidney shaped and ellipse. The axes of kidney shaped or ellipse opening shall be arranged along the bow-stern direction as practice as possible, and the ratio of the length and width of opening shall not less than 2, to insure to reduce the width of opening along the width direction of vessel as practice as possible under the same opening area.b. Make holes on the strengthening deck in the area of the half of the midship, the dimension along the width of ship shall be not over 6% of the distance from the cargo hatch to the side, the width of other opening, kidney shaped or ellipse on deck shall be not over 9% of the distance from the side line of hatch to the side, the rotundity opening shall be not over 6% of the above distance. If the opening does not comply with the above, it shall be complemented its intensity.2.9.4 Forbid opening in the following positionsa. The below part of the transverse elements (beams, cross girders) that there is made opening and end backing strip.b. On the longitudinal strengthening elements (longitudinal frame, stringer).c. On the frame of the upper part of plane keel d. The bracket on end part of the stay.e. After discussing with the hull department, can make holes on the special material for the special vessel type.2.10 Weld fixtures, assembled parts and fabricated sections.2.10.1 Welding shall be fixed, can insure to fasten cables and no sealing off during using.2.10.2 The toes of fixtures and assembled parts shall be not direct welded on the shell below the continual deck. When where is necessary, it shall be welded on the corresponding webs.2.10.3 The cables bracket what is used for complementing intensity on the opening, shall be continual single side welding around the bracket to insure the intensity; on the opening where is not need to be complemented, the bracket is allow to adopt the discontinuous welding.2.10.4 The proof-fire and water tight fabricated parts such as the stuffer holder of cables, cables penetraters, stuffer boxes etc. shall be adopted the around double side welding. After welding and cleaning, shall check the water tight of the welding seam. However the cable brackets on the dry area without the request of proof-fire and water tight is allowed to be continual single side welding.2.10.5 After being welded, all welded parts shall be cleaned and covered the anti-rust paint.3. Principle requirements of laying out cables3.1 Arrangement of cables shall be in straight line and easy to be checked and maintained as practice as possible, and to avoid crossing laying out.3.1.1 When laying out the main cables, the closing plane on the way of laying out cables shall be easily opened.3.1.2 If the branch connection boxes on the cable line is hidden installed, the closing plane shall be easily opened and made the perpetual marker.3.1.3 Cables shall not be in the insulation of compartment, cables of the illumination circuit, plug circuit and control circuit in the accommodation area is allowed to be excepted, but insure that the max loading of cables is not more than 70% of the rate current.3.2 Laying out cables shall be prevented from the machine damage.3.2.1 Avoid laying out cables in the cargo holder, store room, deck, checker plate where is easy to be machine damage as possible. If it is no way to avoid that, it needs to be arranged removable cases or cable pipes to protect. The thickness of the cases in the cargo holder and deck usual is not less than 3mm. The metal cases shall be done anti-corrupt treatment.3.2.2 When the cables pass through the deck, it shall be protected with metal cable pipe, cable penetrater or cables boarding, its highness is usual not less than 200mm, the special one can be flexible treatment.3.3 Laying out cables shall be far from the heat source as possible. The distance from cables to the heat source such as steam pipes, exhaust gas pipes, flanges and boiler usually shall be not less than 100m, when the cable is crossing with the steam pipes or exhaust gas pipes, the distance of net space usually shall be not less than 80mm, or shall be taken the insulation measures3.4 Cables shall be avoided laying out in the area where is damp, congulation, drop, immerged by oil or water. When laying out cables below the checker plate which is easy to be immerged by oil or water, cables shall be laid out in the metal pipes, which shall be fixed close to the checker plate and the two ends of it shall be higher than the checker plate and closed with stuffer.3.5 In the flammable and explosive area, cables shall be armoured or covered with the knitting shield layer, or shall be laid out in the metal pipes. The penetration on the bulkhead or deck must be sealed to avoid the poison gas penetrating.3.6 Cables forbid passing through the oil tank, usually shall not pass through the water tank. When that is no way to avoid, it may adopt the one piece of seamless steel pipes for laying out cables. Welding between the pipes and the bulkhead shall be water tight and anti-corrupt.3.7 The distance from laying out cables to the shell, water partition and deck shall be not less than 20mm, the distance from laying out cables to the lubrication oil tanker, foul oil tanker shall be less than 50mm.3.8 At the bending part, shall be according to the min bending radius allowed by maker, the radius shall at less be not less than 6 times of the outside radius of cables.3.9 The important or emergency power cables, the cables of illumination, communication and signal cables circuit shall be as possible bypassed the galley, laundry, machine space as well as the engine casing where are high fire danger areas. 3.10 The following cables shall be avoided laying out together as possible:a. To the important electric equipment required feeding with two circuits, the two circuits shall be laid out far from each other in the horizon and the vertical direction as possible.b. When the main steer gear plane is arranged two independent control system, the cables of the two system from the wheel room to the steer gear room shall be laid out far from each other.c. The cables with different casing or covered layer shall be considered to lay out divided.3.11 To consider the heat elimination of cables, the section of bunched cables shall be arranged the rectangle to avoid the rotundity or the square, the ratio of length and width of the rectangle is better not less than 3:1.The layer of laying out bunched cables shall be not more than two layer or the thickness of layer is not over 50mm in principle, if necessary it shall be adopted the multi-layer bracket for laying out.3.12 The cables is not relative to the refrigerator shall not pass through the refrigeration area.3.13 The bunched cables are usually fastened on the bracket, when the number of cables is smaller, according to the size of bunched cables, use the bracket made of the flat bar B40,B20 or the round steel 8 for fastening.3.14 The signal cables (24V) from the host computer of monitor, alarm, lever remote control to the extension, computer shall be divided laying out to the power cables that is more than 220V, AC, and the distance shall be more than 100mm as possible, at less not less than 50mm.3.15 The power cables of generator and bigger output applicants shall be divided laying out to the signal cables of the alarm and monitor circuit.4. Drawing cables4.1 Before drawing cables, shall check if there is missing the fixture and fabricated parts in the circuit, if there are sharp edges and burrs, if the welding is fixed and the welding area is painted the anti-rust paint; carefully check the code, size, length of cables and the name of the terminal equipments and jumping off point equipments according to the cables list books and drawings.4.2 Drawing cables shall be executed according to the sequent stated in the list books. the local cables can be cut and drawn as the practical direction of laying out according to the arrangement drawings and electric system drawings. The local cables shall be drawn after finishing laying out the main cables.4.3 When drawing cables, the cables shall be even moving along the direction of laying out cables where are welded fixtures, can not be hard drawn to avoid damaging it. The main cables shall be stop on the stated bulkhead or deck according to the stop marker in the cable.4.4 When cables with the different jackets are mixed and drawn, shall specially pay an attention to avoid the cable damaged by the friction of each other jackets.4.5 After beginning to drawing cables, shall avoid gas cutting and welding closed to the laying out cables as possible, or shall take the temporary protection means.4.6 After drawing every cable, shall tidy up cable and hung the cable coils near the equipment. Do not thrust and step on the cable arbitrarily to avoid damaging it. 4.7 After drawing all cables, shall check roundly to avoid error or missing. Fasten cables after checking. When the number of cables is more, shall divide cables in bunch for laying out. That is at first draw one bunch cables, fasten with tapes after checking and tidying up, then draw the second bunch cables.5. Fixing the cables5.1 The cables on the weather deck, in the area where from the heat source such as boiler is 0.5m, in the refrigeration room, bath etc. shall be fixed with fasten with the multiple plasticated stainless steel tapes.5.2 The vertical laying out bunch cables shall be fixed with the multiple plasticated galvanized steel tapes.5.3 The cables of the main way shall be fixed with the multiple plasticated galvanized steel tapes in principle.5.4 The other cables shall be fixed with nylon tapes. When fixing cables with nylon in the important compartments (such as engine room, auxiliary engine room etc.), shall fix with one piece o