Insulating Joint is an apparatus installed on oil and gas pipelines to prevent the flow of electrical current injected into the pipes for cathodic protection. Integrated insulating joints are used to electrically isolate pipelines from other equipment and pipelines. The aim is to establish electrical isolation between segments. Insulating joints are used to assure effective current distribution for cathodic protection systems. Its electrical resistance is more than 4M? with a DC current of 1000V and it is also resistant against electrical fracture with AC current of 50 HZ to 3000V .
Insulating Joints withstand high pressures according to the following table. As per the related standard , diameter size of insulating joints ranges from 2-56” in three classes of 150 , 300, 600,900,1500,2500.
Gas souzan Co is the sole manufacturer of this product in iran.
Test Carried out on this product are as follows:
• Weld inspection by RT radiography.
• Ultrasonic inspection of finished welds.
• Hydrostatic pressure test with maximum test pressure acc to table.
• Belding test with hydrostatic pressure
• Paint thickness control
• Electrical resistance measuring in 1000V DC
• Insulating fracture resistance measuring in 3000V AC specifications of Gas Souzan ‘s insulating joints are according to the following tables and drawing.
The tavle is according to ASME/ANSI B16.5
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Without Temperature Range
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38C to 93C
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-28C to 38C
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Temperature Range
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Max. .test
pressure
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MAX. working pressure
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MAX. working pressure
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ANSI Class
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|
450 psig
|
260 psig
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285 psig
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150
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31 bar
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17.93 bar
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19.65 bar
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1125 psig
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675 psig
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740 psig
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300
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bar 77.6
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46.55 bar
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51 bar
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2175 psig
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1350 psig
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1480 psig
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600
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|
150 bar
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93.1 bar
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102 bar
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3330 psig
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2025 psig
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2220 psig
|
900
|
|
229.6 bar
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139.6 bar
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153.1 bar
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|
5557.5 psig
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3375 psig
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3705 psig
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1500
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|
383.3 bar
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232.75 bar
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255.5 bar
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9255 psig
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5625 psig
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6170 psig
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2500
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|
638.3 bar
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387.9 bar
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425.5 bar
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Insulating Part List
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NUM
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MATERIAL
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STANDARD/SUBSTANCE
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1
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Pipe
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API 5L :B,X42,X52,X60,X65
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2
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Steel Flange
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ASTM A105&ASTM A694
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3
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Steel Flange
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ASTM A105&ASTM A694
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4
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Steel Ring
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ASTM A105&ASTM A694
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5
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Insulating Ring
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ASTM D709:G10 or G11
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6
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Insulating Ring
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ASTM D709:G10 or G11
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7
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Sealing
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ASTM D2000: VITON
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8
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Filling
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Epoxy Resin
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|
9
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Internal Coating
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BS 5493 SK4) or ( IPS
M TP 750/8))
|
|
10
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External Coating
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BS 5493 SK4) or ( IPS
M TP 750/8))
|
|
11
|
Edging
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MSS SP 75 ASTM/ANSI B31.8
|
|
12
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Weld
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ASTM/ANSI B31.8 ASME Sec VIII,IX
|
|
13
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Filling
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Epoxy Resin
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Insulating Joints
