close
Choose Your Site
Global
Social Media
| Quantity: | |
|---|---|
Overview
BS 4504 Blind Flanges manufactured to BS 4504 Code 105 (PN40) are designed to securely seal the end of a pipeline, valve, or pressure vessel opening.
With a solid plate structure and no central bore, these blind flanges provide reliable isolation, pressure containment, and long-term sealing performance in high-pressure systems.
BS 4504 PN40 blind flanges are widely used in water transmission, fire protection, oil & gas, petrochemical, power generation, and industrial processing systems, especially in projects following British and European flange standards.
Product Description
A BS 4504 PN40 Blind Flange (Code 105) is a circular, solid stainless steel plate with precision-drilled bolt holes that match BS 4504 PN40 mating flanges.
Standard: BS 4504
Code: 105
Pressure Rating: PN40
Type: Blind Flange (BL)
Size Range: DN15 – DN600
| Model Number: | BS4504 BLIND105 |
| Standard: | BS4504 BLIND105 PN6 PN10 PN16 PN25 PN40E |
| Product name: | BLIND Flange |
| Material: | Q235 /A105/ ST37/S235JR/ CT20 /SS400/16MN/SS321/SS304/SS316/S235/P245GH/P250/P91/904L |
| Pressure: | PN6 PN10 PN16 PN25 PN40 |
| Technics: | Forged |
| Connection: | Welding |
| Surface Antirust: | Antirust light oil、 Black paint coating、Yellow paint coating or Red paint coating、Galnavized (Hot galvanized or Cold galvanized or Electro Galvanized) |
| Certificate: | ISO, CE, PED, BV, KS |
 |  |  |  |
Flange production process
Factory Showcase
 |  |  |
 |  |  |
For safe installation and optimal sealing performance, follow these steps:
Check Specifications
Verify DN size, PN40 rating, material grade, and bolt pattern before installation.
Inspect Flange Faces
Ensure both flange faces and sealing surfaces are clean and undamaged.
Select Proper Gasket
Choose a gasket suitable for PN40 pressure and service media
(spiral wound, graphite, PTFE, or metal-reinforced gasket).
Align Bolt Holes
Position the blind flange accurately against the mating flange.
Tighten Bolts Evenly
Use a cross-tightening pattern and apply torque gradually and uniformly.
Pressure Test
Perform hydrostatic or pneumatic testing to confirm leak-free installation.
Tip: Always follow recommended torque values and gasket manufacturer instructions.
FAQ
Q1: What is BS 4504 Code 105?
BS 4504 Code 105 corresponds to PN40 pressure rating, defining flange dimensions and pressure performance.
Q2: Can BS 4504 blind flanges be used as permanent closures?
Yes. They are suitable for both permanent sealing and temporary isolation, depending on system design.
Q3: Are BS 4504 blind flanges interchangeable with EN 1092-1 flanges?
BS 4504 is the predecessor of EN 1092-1. While many dimensions are similar, interchangeability should be confirmed case by case, especially for PN40 systems.
Q4: Which gasket type is recommended for PN40 applications?
Spiral wound or metal-reinforced gaskets are commonly recommended for high-pressure PN40 systems.
Q5: Are custom materials, sizes, or markings available?
Yes. Custom sizes, materials, coatings, and project-specific markings can be supplied upon request.
