1.In order to make design, construction and acceptance of building water supply composite pipe lined stainless steel pipeline project with advanced technology, reasonable economical, safe and health and ensure quality, draw up this regulation.
2.This procedure is applied to transportation pipelines of drinking hot and cold water, drinking water and other media in the industrial and civil buildings.
3.Composite pipe lined stainless steel of water supply system should comply with the current Ministry of Construction CJ/T192-2004 standard.
4.Composite pipe lined stainless steel of water supply system should meet the following requirements:
5.In addition to the implementation of this regulation, design/construction and acceptance of building water supply composite pipe lined stainless steel pipeline project should be in line with the provisions of the existing national standards.
This pipe is to line a certain thickness of stainless steel with standard galvanized pipe so as to make them compound closely.
Press notch at the end of pipe. Fasten groove to connect by a special clamp, combined with rubber seals.
This process is to press standard notch by using pressing wheel on the end of rotating pipe.
1.When the working pressure of pipeline system is no more than 2.5Mpa, use galvanized steel pipe or welding pipe lined with stainless steel composite tube, malleable iron pipe fittings lined with stainless steel, and threaded connection.
2.When the working pressure of pipeline system is more than 1.6MPa and no more than 3.0MPa, use low-pressure fluid pipes lined with stainless steel composite tube, tube lined stainless steel or stainless steel pipe fittings and flange connection or welding connection.
3.When the working pressure of pipeline system is more than 1.6MPa and less than 2.5MPa, use low/middle-pressure fluid pipes lined with stainless steel composite tube, tube lined stainless steel or pure stainless steel pipe fittings and flange connection or welding connection.
4.When the diameter of pipe is no more than 100mm, use threaded connection; when the diameter of pipe is more than 100mm, use flange connection or groove connection.
Pipelines which immerse in water should use tubes covered with plastic both inner and outside and lined with stainless steel and drain pipe covered plastic outside and lined with stainless steel; Outlet pipe should use pipe covered plastic outside and lined with stainless steel. The supporting and fastening units of pipeline should use metal supporting unit which is processed with anti-corrosion treatment. Parts of the pipeline through the reinforced concrete pools (boxes) should use corrosion-resistant and waterproof casing pipe.
6.In the hot water supply pipeline system, use malleable iron pipe fittings lined with stainless steel or full stainless steel pipe fittings. Rubber seal of these pipes should use heat resistant rubber seals. When use tubes lined with plastic, use these lined with PP and PVC-C.
7.Composite steel pipe lined with stainless steel which is underground should be adopted with reliable anti-corrosion measures on the outside wall of pipe.
2.Friction factor of re-crystallized stainless steel composite pipe can be calculated as follows:
When design calculations, obtain by hydraulic calculation table of the first volume "useful information" of "Water Supply and Drainage Design Manual".
1.In regard of water supply system which is used of malleable iron pipe fittings lined with plastic and threaded connection, local resistance of water distribution segment can be determined by resistance along the way multiplied by the percentage. Percentage can be adopted according to the following provisions:
2.In regard of water supply system which use steel pipes lined with plastic and use flange connection or groove connection , local resistance can be calculated by 10%~20% of resistance along the way.
Anti-cold and heat preservation
Anti-cold
1.Outdoor composite steel pipe lined with stainless steel should be buried under the frozen line.
2.In the case of clear dew outdoor or freeze indoor, composite steel pipe lined with stainless steel should adopt anti-cold and heat preservation measure.
Heat preservation and insulation
1.Obvious announced hot water pipes in the room should be heat preservation and insulation. Anti-condensation measures should be taken in place where may condensate.
2, Thickness of insulation materials of wall pipe should be calculated according to the length of the pipe, the water temperature, environment temperature and water supply time.
3, Thermal conductivity of composite tube lined with stainless steel can be determined by the following formula:
In this formula
λ——Thermal conductivity of composite tube lined with stainless steel (W/m.K)
λ1——thermal conductivity of the outer layer of galvanized steel, usual takes 54W/m.K;
δ1——calculated wall thickness of the outer layer of galvanized steel(mm), calculated diameter, wall thickness of galvanized or non-galvanized welded steel pipe is determined by CJ/T192-2004 standard;
λ2——thermal conductivity of inner stainless steel, usual takes 25W/m.K;
δ2——calculated wall thickness of inner stainless steel (mm)
4, Because galvanized or non galvanized steel pipe and stainless steel pipe have same properties and their thermal conductivity are the same level, in general cases and in order to calculate conveniently, treat composite tube lined with stainless steel as one and its thermal conductivity is 50W/m.K.
Pipeline installation
● General provisions
1, Prior to installation, pipeline shall meet the following conditions：
⑴Complete construction drawings and other technical documents. Do Technical exchanges.
⑵In regard of accessories such as pipe, fittings and valves which are necessary for installation , as well as pipe supporting units, fastening units, seals, check product certification, quality assurance and specifications, the variety and quantity, and do visual inspection.
⑶Construction site and water supply of construction, power supply can meet the requirements.
⑷Construction equipment has arrived at the scene.
⑸The equipment for pipe connection has been in place fixed or has been targeted.
2, Construction personnel should be technically trained to be familiar with the performance of the composite pipe lined with stainless steel and master basic skills.
3, Composite pipe lined with stainless steel should use the following construction equipments:
⑴Cutting should use abrasive cutter
⑵Die head thread should use automatic die head threading machine；
⑶Pressing groove should use special grooving machine
⑷Elbow pipe should be coldly bended by the bending machine
4, Construction procedure of composite tube lined stainless steel should meet the following requirements:
⑴Indoor underground pipe should be installed before the underlying civil floor construction;
⑵Indoor underground pipe should be installed exceed the wall more than 500mm and the nozzle should be timely plugged;
⑶Composite pipe lined with stainless steel should not be buried in the reinforced concrete structure;
⑷Pipeline installation should be connected gradually from large-caliber to small-caliber.
5, When the pipeline passes through the floor, roof, water tank (pool) wall (bottom), it should reserve holes or pre-buried casing tube, and shall meet the following requirements:
⑴Size of hole reserved should be the outer diameter plus 40mm;
⑵When open ducts as the pipes are hidden announced in the wall. The width of the ducts should be the outer diameter of pipe plus 30mm; and the slope of the ducts should be pipe slope;
⑶Pre-bury waterproof casing tubes in places of reinforced concrete water tank (pool)where the inlet pipe, outlet pipe, vent pipes, overflow pipes pass through and fill them with dense waterproof clay.
6, When the pipe diameter is no more than 50mm, coldly bend with bending machine, but the bending radius of curvature should be no less than eight times of the diameter, and the bending angle is 10 °.
● Threaded connection
1、Pipe cutting shall meet the following requirements:
1) Pipe cutting should use abrasive cutter, and also be cut by cutting tools which do not affect the quality of composite steel lined with stainless steel. When use a circular saw cutter, the speed shall not be greater than 800r/min; at the beginning, the cutting speed should be slow and accelerate the cutting speed when the tube is cut through.
2) When use a hand-saw to cut the tube, its sawing surface should be perpendicular to the tube axis, don’t break it by hand before finishing sawing.
2、 Die head thread shall meet the following requirements:
（1） Die head thread should use automatic die head threading machine;
（2） Die head threading machine should be used lubricating oil;
（3） Conical pipe thread should be in line with requirements of current national standards "sealed with screw pipe threads” GB/T7306 and shall use the standard thread gauge to test.
3、 Processing of end-of-pipe clean-up shall meet the following requirements:
（1）
Use a finishing file to repair the burrs of the metal tube end smoothly;
（2） Remove oil, water and metal chips on the end of pipe and within thread by cotton waste and brush;
（3） Prune flat the common ending surface of composite pipe lined with stainless steel; uniformly coat with a layer of food-grade epoxy resin.
4、 After cleaning the pipe ends and pipe thread, do embalmed and sealed treatment by anti-rust sealant and Teflon tape wrapped thread, at the same time use a color pen to mark the screw-in depth on the pipe wall.
5、 Don’t use ordinary malleable iron pipe fittings.
6、 Before connecting the tube with accessories, check the rubber seals or anaerobic sealant of malleable iron pipe fittings lined with stainless steel and malleable iron pipe lined with plastic, and then twist the pipe end threaded by hand. After confirming that the pipe connector has been inserted into composite pipe lined with stainless steel, connect the pipe with accessories by pipe wrench according to table 6.2.6.
Note: No reverse rotation.
Table 6 Standard screw-in number of teeth and standard robust torque
|
Nominal diameter
|
Screw-in
|
Torque
|
|
(mm)
|
length (mm)
|
Threads
|
Number
|
N.m
|
|
15
20
25
32
40
50
65
80
100
|
11
13
15
17
18
20
23
27
33
|
6.0-6.5
6.0-6.5
6.5-7.0
7.0-7.5
7.0-7.5
9.0-9.5
10.0-10.5
11.5-12.0
13.5-14.0
|
40
60
100
120
150
200
250
300
400
|
400350×0.15
350×0.25
450×0.30
450×0.35
600×0.30
600×0.40
900×0.35
900×0.40
1000×0.50
|
7, After connection of pipe and accessories, coat anti-rust sealant on exposed threaded portion, all clamp marks and damaged surface portions.
8, Curing period of the tube connector which is sealed with anaerobic sealant should be no less than 24h. During this period, no pressure test can be taken. Tube connector which is sealed with seal has no curing period. Do the pressure test at once after installation.
9, Composite pipe lined with stainless steel can’t be directly connected with valve. Use special transition pipe to transit before connection.
10 , Composite pipe lined with stainless steel can’t be directly connected with hydrant. Use dedicated yellow copper internal thread pipe connector.
11, When connect the composite pipe lined with stainless steel with copper tube and plastic tube, use dedicated transition connector.
12 , When connect the composite pipe lined with stainless steel with tube fittings and accessories of other materials, coat with food-grade epoxy polyester on the end of the outer thread to do anticorrosive treatment.
● Flange connection
1, The flange used in composite pipe lined with stainless steel should meet following requirements:
⑴ Convex plate flat welded steel pipe flanges shall comply with the requirements of the current national standard "convex plate flat welded steel pipe flanges" GB/T9119.5 ~ 9119.10
⑵ Convex with a neck screwed steel pipe flange shall comply with the requirements of the current national standard “Convex with a neck screwed steel pipe flange” GB/T9114.1~9114.3 and is only applicable to connection of composite pipe lined with stainless steel which nominal diameter is not greater than 150mm.
⑶ Pressure grade of flange should match with working pressure of pipeline.
2, Onsite flange connection of composite pipe lined with stainless steel should meet following requirements:
⑴ Cut-off pipe of composite pipe lined with stainless steel should conform to the requirements of this regulation 6.2.1;
⑵ When connect flange on site, use convex with a neck screwed steel pipe lined with plastic flange;
⑶ The connected composite pipe lined with stainless steel should use pipe thread which is for thread sealing and its tooth type should be consistent with the requirements of the current national standard “pipe thread which is for thread sealing” GB/T7306.
● Groove connection
1, The groove connection is applicable for connection of composite pipe lined with stainless steel which nominal diameter is not less than 65mm.
2, Grooved pipe connector should be consistent with current national product standards
3, The working pressure of grooved pipe connector should match with working pressure of pipeline.
4, Grooved pipe connector used for hot water transportation should use heat resistant rubber seals. The rubber material used for drinking water pipeline should comply with the requirements of current national standards "security evaluated criteria of drinking water, water distribution equipment and protective materials" GB/T17219.
5, In regard of composite pipe lined with stainless steel, when process the groove on site and install pipeline, its construction shall meet the following requirements:
⑴ Give priority to the use of the finished grooved stainless steel fittings or plastic coated pipe;
⑵ The length of pipe-connector should be net length between two pipe ends minus 6~8mm broken material, there should be3~4mm space between each connector and numbered with steel mark;
⑶Use grinding wheel to cut pipe and the cutting section should be vertical with axis: The allowed deviation is: pipe diameter no more than 100mm, deviation no more than 1mm; pipe diameter more than 125mm, deviation no more than 1.5mm;
⑷ The outer wall surface of tube should be mechanically processed a fillet which is 1/2 of wall thickness;
⑸ Use special grooving machine to press notch and the pipe should be kept level. Steel pipe and stopping surface of grooving machine appear 90 °. Continued gradually press notch and the depth of groove should meet the requirement of table 6.4.5; and measure the circle depth with standard gauge. If the groove is too shallow, adjust grooving machine and then process.
Table 5 The standard depth and tolerance of groove
|
Pipe diameter
|
Depth of groove
|
Tolerance
|
|
≤80
|
2.20
|
+0.3
|
|
100~150
|
2.20
|
+0.3
|
|
200~250
|
2.50
|
+0.3
|
|
300
|
3.0
|
+0.3
|
Note: if the groove is too deep, treat as reject.
⑹ The outer end of pipe which connected with rubber seal should be flat and smooth and with no burr which scratch rubber ring or impact seal’
6, The groove connection of composite pipe lined with stainless steel is used for onsite measure and installation.
7, Coat with anti-rust paint on the end of pipe and outside sections which contact with rubber seal ring. The anti-rust paint should be consistent with existing national standards.
8, The groove connection of composite pipe lined with stainless steel should be done according to following procedures:
⑴ Check whether the rubber seal match or not, coat lubricant and entangle on the end of pipe; entangle on the docking pipe and move the apron to the center of the connection segment.
⑵ Entangle the clamp on the apron and snap the edge into the groove.
⑶ Insert bolt with deformed block to the hole and tighten the nut.
Note: Tighten symmetrically and alternately to prevent the apron wrinkle
9, The largest supporting space of pipes should meet requirements of table 6.4.9:
Table 9 The largest supporting space of pipes
|
Pipe diameter (mm)
|
The largest supporting space (m)
|
|
60-100
|
3.5
|
|
125-200
|
4.2
|
|
250-315
|
5.0
|
Note: ⑴ there should be support between any two connectors of horizontal tube
⑵ Don’t support on the connector.
10, Grooved connection pipes have no need to consider the compensation of the pipe due to thermal expansion and contraction.
11, When bury grooved stopped hoop connector used for pipe, its anti-corrosion measures should be the same as the pipe section.
