EN 1092-1 Type 04 loose plate flange assembly with integral weld-neck collar. DN10-DN300, PN2.5-PN40. Ideal for high-pressure lap joint applications requiring frequent assembly/disassembly.
The EN 1092-1 Type 04 Loose Plate Flange Assembly consists of two components: a Loose Plate (flange ring) and a Weld-Neck Collar (integral hub collar). The weld-neck collar is butt-welded to the pipe end, providing a smooth bore transition and excellent stress distribution. The loose plate is free to rotate around the collar, enabling rapid assembly and disassembly without moving the adjacent pipe or equipment.
Compared with Type 02 (Loose Plate with plain collar), the weld-neck collar of Type 04 offers superior reinforcement at the weld joint and improved alignment with the pipe bore — making it the preferred choice for higher pressure and more demanding service conditions.
| Feature | Type 02 | Type 04 |
|---|---|---|
| Collar type | Plain collar (plate collar / lapped pipe end) | Weld-neck collar (hubbed) |
| Pressure range | PN2.5 – PN40 | PN2.5 – PN40 |
| Size range | DN10 – DN500 | DN10 – DN300 |
| Weld reinforcement | Standard fillet weld | Full butt-weld with tapered hub |
| Bore alignment | Acceptable | Precise alignment via integral hub |
| EN 1092-1 Annex A group | Group 2 (thin-walled) | Group 1 (standard) |
| Parameter | Specification |
|---|---|
| Standard | EN 1092-1: 2018, Type 04 |
| Equivalent DIN | DIN 2672 (weld-neck collar) |
| Size Range | DN 10 – DN 300 |
| Pressure Rating | PN 2.5, PN 6, PN 10, PN 16, PN 25, PN 40 |
| Face Finish | Type A (Flat Face), Type B (Raised Face), Type C (T&G) |
| Materials | X5CrNi18-10 (1.4301), X2CrNiMo17-12-2 (1.4404), X2CrNiMoN22-5-3 (1.4462), X2CrNiMoN25-7-4 (1.4410), NiCr22Mo9Nb (2.4856), NiCu30Fe (2.4360) |
| Surface Finish | Pickled & passivated, anti-rust oil, or matte polished |
| Face Finish (RF) | Ra 3.2 – 12.5 μm per EN 1092-1 |
| Dimension | Value (mm) |
|---|---|
| Bore (B) | 108.0 |
| Outside Diameter (D) | 220.0 |
| Hub Diameter at Back (H) | 114.3 |
| Collar Outside Diameter (Dm) | 133.0 |
| Thickness of Plate (t) | 20.0 |
| Thickness of Collar (s) | 6.3 |
| Length of Collar (L) | 42.0 |
| Bolt Circle (k) | 180.0 |
| Bolt Hole Diameter | 18.0 |
| Number of Bolts | 8 |
| Bolt Size | M16 |
Note: Dimensions per EN 1092-1. All dimensions in mm unless stated. For full DN/PN range, refer to EN 1092-1 tables or request our dimensional PDF.
| EN Designation | Mat. No. | UNS |
|---|---|---|
| X5CrNi18-10 | 1.4301 | 304 |
| X2CrNi18-9 | 1.4306 | 304L |
| X5CrNiMo17-12-2 | 1.4401 | 316 |
| X2CrNiMo17-12-2 | 1.4404 | 316L |
| X6CrNiTi18-10 | 1.4541 | 321 |
| X6CrNiNb18-10 | 1.4550 | 347 |
| EN Designation | Mat. No. | UNS |
|---|---|---|
| X2CrNiMoN22-5-3 | 1.4462 | S32205 |
| X2CrNiMoN25-7-4 | 1.4410 | S32750 |
| X2CrNiMoCuWN25-7-4 | 1.4501 | S32760 |
| EN Designation | Mat. No. |
|---|---|
| X1NiCrMoCu25-20-5 | 1.4539 |
| X1CrNiSi25-21 | 1.4361 |
| EN / Alloy Name | Mat. No. | UNS |
|---|---|---|
| NiCr22Mo9Nb | 2.4856 | N06625 |
| NiCr21Mo | 2.4858 | N06625L |
| NiCu30Fe | 2.4360 | N04400 |
| NiMo16Cr15W | 2.4819 | N10276 |
| NiCr15Fe7TiAl | 2.4669 | N07718 |
Per EN 1092-1, each Type 04 loose plate and weld-neck collar is permanently marked with: Manufacturer / Standard / Type / Size / Pressure Rating / Material designation / Heat Number.
Example (Loose Plate): JIAJI · EN 1092-1-04 · DN100 · PN16 · 316L · HEAT-2024-001
Example (Weld-Neck Collar): JIAJI · EN 1092-1-04-COLLAR · DN100 · PN16 · 316L · HEAT-2024-001
Optional certifications: CE marking (PED 2014/68/EU), EN 10204 3.1/3.2 inspection certificates, NACE MR0175 / ISO 15156, IBR, API 6A. Full material traceability and test reports available.
Both Type 02 and Type 04 are loose plate flanges used in lap joint assemblies. The key difference is the collar type: Type 02 uses a plain plate collar or lapped pipe end, while Type 04 uses a weld-neck collar (integral hub). The weld-neck collar provides a tapered hub that transitions smoothly from the pipe bore, offering better mechanical strength at the weld joint and more precise bore alignment. Type 04 is typically preferred for higher-pressure or more demanding applications.
Type 04 loose plate flanges with weld-neck collars are available in PN2.5, PN6, PN10, PN16, PN25, and PN40 per EN 1092-1. The size range is DN10 to DN300.
No. Type 04 uses a dedicated weld-neck collar with a specific bore geometry and flange thickness designed for Type 04 loose plates. Mixing collar and plate types is not recommended as it can compromise sealing integrity and pressure containment.
JIAJI FORGING manufactures Type 04 loose plates and weld-neck collars in austenitic stainless steel (304/304L, 316/316L, 321, 347), duplex and super duplex stainless steel (2205/2507/1.4501), super austenitic (904L), and nickel alloys (Inconel 625/600, Hastelloy C276, Monel 400). Custom alloys available on request.
Loose plate with plain collar. DN10-DN500. PN2.5-PN40. Cost-effective lap joint solution.
View Details →Full bore closure. DN10-DN2000. PN2.5-PN400. No flow connection.
View Details →Integral weld neck. DN10-DN2000. PN2.5-PN400. Full structural reinforcement.
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