One-piece Stainless Steel Insulating Joint for Oil & Gas Pipeline Metal Expansion Bellows
DN50-DN3200
A monolithic insulating joint (MIJ) is a boltless, factory - prefabricated and welded integral pipeline component. Its core function is to achieve reliable electrical isolation between pipeline segments while ensuring sealing and pressure - bearing capacity, which is a critical part of the cathodic protection system for steel pipelines in the oil, gas, and water transmission industries.
Delivery
EXW,FOB,CIF,CFR,DAP
minimum order
1 piece
Supply Ability
100piece / Day
Country of Origin
China
Stock Time
10-15Day
Quantity:
US $1.00 - US $999.00
/ piece
Product Description
Product Description
A monolithic insulating joint (MIJ) is a boltless, factory - prefabricated and welded integral pipeline component. Its core function is to achieve reliable electrical isolation between pipeline segments while ensuring sealing and pressure - bearing capacity, which is a critical part of the cathodic protection system for steel pipelines in the oil, gas, and water transmission industries.
Core Structure
It mainly consists of upper pipe, lower pipe, sleeve, insulation components, sealing elements, and insulation coating. Insulation parts and seals are clamped between the butt - end faces of the upper and lower pipes to form a double - sealing structure with insulation performance. The sleeve tightly wraps the insulation components and the upper and lower pipes through groove welding, forming a sealed container to ensure insulation effectiveness and pressure resistance.
Key Technical Specifications
| Parameter | Typical Value |
|---|---|
| Pressure Rating | PN1.0-PN40 MPa (ANSI 150-900) |
| Operating Temperature | -30°C to 90°C (standard); -173°C to 180°C (special customization) |
| Insulation Performance | Insulation resistance ≥10 MΩ (DC 1000V); withstand 2500V, 50Hz voltage for 1 minute without breakdown/arcing |
| Test Pressure | Hydrostatic test: 1.5× design pressure; Pneumatic test: equal to design pressure |
| Service Life | Consistent with the connected pipeline (≥20 years under normal conditions) |
Core Advantages
- Superior Electrical Isolation: Blocks stray current and prevents electrochemical corrosion, significantly improving the efficiency of the cathodic protection system.
- High Structural Integrity: Bolt - free integral design, with strength matching the pipeline, and a double - sealing structure ensuring long - term leak - proof performance.
- Low Installation & Maintenance Costs: Factory - assembled and fully tested, requiring only on - site butt welding for installation; suitable for direct underground burial without the need for observation wells.
- Good Adaptability: Compatible with pigging operations and suitable for most hydrocarbon and water - based media.
Typical Applications
- Oil & Gas Pipelines: Isolate pipe sections to ensure the effect of cathodic protection and prevent corrosion caused by stray current.
- Petrochemical Plants: Used for the isolation of process pipelines containing corrosive media to avoid cross - segment electrical interference.
- Urban Gas Networks: Applied in pipeline branches and pressure - grade transition sections to enhance operational safety.
Installation & Quality Control
- Weld - end bevels shall be properly prepared; no welded dead ends shall be left within 50 meters of the installation position.
- No pipeline lifting is allowed within 5 meters of the joint after installation to avoid structural damage.
- 100% factory hydrostatic, electrical insulation, and leak - tightness tests are mandatory to ensure reliability before delivery.
FAQ
a) How can I get more details about your products?You can send an email to our email address. We will provide catalogue and pictures of our products for your reference.We can also supply pipe fittings, bolt and nut, gaskets etc. We aim to be your piping system solution provider.
b) How can I get some samples?
If you need, we will offer you samples for free, but new customers are expected to pay express charge.
c) Do you provide customized parts?
Yes, you can give us drawings and we will manufacture accordingly.
d) To which country have you supplied your products?
We have supplied to Thailand, China Taiwan, Vietnam, India, South Africa, Sudan, Peru , Brazil, Trinidad and Tobago, Kuwait, Qatar, Sri Lanka, Pakistan, Romania, France, Spain, Germany, Belgium, Ukraine etc. (Figures here only include our customers in latest 5 years.).
e) I can't see the goods or touch the goods, how can I deal with the risk involved?
Our quality management system conforms to the requirement of ISO 9001:2015 verified by DNV. We are absolutely worth your trust. We can accept trial order to enhance mutual trust.
