UPVC Blind Flange

A blind flange is a type of pipe fitting used to close the end of a piping system or pressure vessel openings, preventing the flow of fluids or gases. Unlike other types of flanges, a blind flange has no central opening, making it a solid disk that provides a secure seal.

Blind flanges are crucial components in piping systems designed to block off sections of pipelines or vessel openings. They are essentially solid discs used to cover or close the end of a pipe, valve, fitting, or equipment nozzle. UPVC blind flanges play a vital role in terminating or isolating piping systems, especially during non-destructive testing such as hydrostatic testing. They offer the flexibility to expand the piping system or install new equipment in the future. Proper selection and installation of upvc blind flanges are essential to ensure the integrity and safety of the piping system, as they must withstand factors such as pressure, temperature, and pipe size.

UPVC Blind Flange Details

L – Flange Diameter
H – Height/Thickness
U – Number of Bolt Holes

Size (Inch)	L (mm)	H (mm)	U (No. of Holes)
1″	115	15	4
1½”	136	18	4
2″	160	18	4
2½”	176	23	4
3″	188	23	4
4″	225	28	8
6″	278	28	8

Parameter	Details
Material	UPVC (Unplasticized Polyvinyl Chloride)
Size Range	½” to 12” (15 mm to 315 mm)
Flange Type	Blind Flange (Solid Disc)
Connection Type	Flanged with Backing Ring
Operating Pressure	Up to 10 bar (150 psi)
Temperature Range	0°C to 60°C (32°F to 140°F)
Color	Generally Grey
Standards Compliance	ASTM, DIN, ISO

Leak-Proof Sealing: Effectively closes the pipe end to prevent fluid leakage.
Corrosion and Chemical Resistant: Ideal for aggressive and corrosive fluid environments.
Strong and Rigid Construction: Designed to withstand high pressure and mechanical stress.
Reusable and Removable: Allows easy access to the pipeline for maintenance or future extensions.
UV and Weather Resistant: Suitable for both indoor and outdoor installations.
Compatible with Standard Backing Rings: Works with metal or plastic flanges.

UPVC Blind Flange Pressure Rating (at 20 °C)

DIN / ISO Standard (PN Rated)

Nominal Size (DN)	Flange OD (mm)	Typical PN Rating	Max Working Pressure
DN 15	95	PN10 / PN16	10–16 bar
DN 20	105	PN10 / PN16	10–16 bar
DN 25	115	PN10 / PN16	10–16 bar
DN 32	140	PN10 / PN16	10–16 bar
DN 40	150	PN10 / PN16	10–16 bar
DN 50	165	PN10 / PN16	10–16 bar
DN 65	185	PN10	10 bar
DN 80	200	PN10	10 bar
DN 100	220	PN10	10 bar
DN 125	250	PN10	10 bar
DN 150	285	PN10	10 bar
DN 200	340	PN10	10 bar

Temprature

Fluid Temperature	Allowable Pressure (%)
20 °C	100%
30 °C	80%
40 °C	63%
50 °C	50%
60 °C (max)	40%

Property	Typical Value	Unit	Notes
Density	1.38 – 1.45	g/cm³	Lightweight compared to metals
Color	Grey / Dark Grey	—	Standard industrial color
Surface Finish	Smooth	—	Reduces fouling and buildup
Chemical Absorption (24 h)	≤ 0.1	%	Excellent moisture resistance
Hardness (Rockwell)	R110 – R120	—	High rigidity
Tensile Strength	45 – 55	MPa	Indicates material strength
Flexural Strength	80 – 95	MPa	Resistance to bending
Impact Strength (Charpy)	2 – 5	kJ/m²	Lower than PP / PE (notched)
Elastic Modulus (Young’s)	2,800 – 3,300	MPa	High stiffness
Thermal Expansion Coeff.	5 – 8 × 10⁻⁵	/°C	Higher than metals
Vicat Softening Temp	75 – 85	°C	Max continuous use typically ≤ 60 °C
Max Service Temperature	60	°C	For pressure applications
Min Service Temperature	−10	°C	Below this becomes brittle
Electrical Conductivity	Insulating	—	Non-conductive
UV Resistance	Moderate	—	UV-stabilised grades recommended

If you are searching for customized product designs that meet your requirements, don’t worry. Petron Thermoplast also offers custom product manufacturing services to meet the unique needs of various industries. Work with our expert engineers to create custom designs suited for your application.

Benefits of Using UPVC Blind Flange

1. Excellent Corrosion Resistance

uPVC does not rust or corrode
Ideal for chemical, wastechemical, and marine applications
Resistant to many acids, alkalis, and salts

2. Lightweight and Easy Handling

Much lighter than metal blind flanges
Easier to transport, install, and remove

3. Quick to install

Lower material and installation costs compared to stainless steel or carbon steel
No need for corrosion protection coatings or cathodic protection

4. Reliable Sealing and Isolation

Provides a positive shut-off at the pipe end
Commonly used for pressure testing, maintenance isolation, and future expansion.
When properly gasketed, offers leak-tight sealing.

5. Low Maintenance

No painting or anti-corrosion treatment required
Long service life in suitable pressure and temperature ranges

6. Good Chemical Compatibility

Suitable for chemical treatment plants, chemical dosing lines, and industrial effluent systems
Maintains integrity in aggressive fluid environments

7. Electrical Insulation

Non-conductive material
Useful in systems where electrical isolation is required

8. Smooth Internal Surface

Prevents buildup of scale and deposits
Helps maintain flow cleanliness when removed or replaced

9. Easy System Modification

Can be removed later to extend piping systems
Ideal for temporary or permanent line termination

UPVC Blind Flange Details

Standard blind flanges are the most commonly used type. They are simple, flat, and solid discs designed to block off a section of pipe or valve.

Features:

• Flat Face: Provides a smooth surface for sealing.
• Bolt Holes: Standardised for easy installation with bolts and gaskets.
• Material Variability: Available in various materials like stainless steel, carbon steel, and alloys.

Applications:

Pipelines: Used to terminate the end of a piping system.
Valves and Pumps: Close off unused valve or pump connections.
Maintenance Points: Facilitate easy access for maintenance or inspection.

Features:

Raised Face: Enhances sealing performance.
Versatility: Compatible with different gasket types.
Pressure Handling: Suitable for higher pressure applications.

Applications:

Chemical Processing: Ideal for sealing high-pressure chemical pipelines.
Oil and Gas: Common in high-pressure oil and gas systems.
Chemical Treatment: Used in systems requiring a strong seal to prevent leaks.

RTJ blind flanges feature a groove cut into their face, which accommodates a metal ring gasket, providing a high integrity seal.

Features:

Metal Ring Gasket: Ensures a leak-proof seal.
High Pressure and Temperature: Suitable for extreme conditions.
Reusability: Gaskets can be reused multiple times.

Applications:

Refineries: Common in high-temperature and high-pressure environments.
• Offshore Platforms: Used in subsea pipelines where reliability is crucial.
• Petrochemical Plants: Ensures secure sealing in hazardous environments.

Why Choose Petron Thermoplast ?

Petron Thermoplast specialises in manufacturing world-class sewerage & drainage systems for both residential and commercial applications and UPVC systems that find applications in industrial and infrastructure projects. As a leading UPVC blind flange manufacturer in India, Petron Thermoplast also serves the agriculture sector through products in the borewell and agriculture chemical categories. The world’s largest manufacturers and inventors of UPVC compounds give us a sharp competitive edge amongst flange companies in India, as we exclusively bring Prince SmartFit Plus [UPVCsystems] to the market – the first choice globally for potable Chemical applications. Petron Thermoplast’s robust distribution network, combined with best-in-class technology, is set to create a strong & sustainable partnership in the chemical Industry.

UPVC Pipe Fittings

We offer UPVC Pipe Fittings products in all standard sizes and provide complete customization options to meet your specific project requirements across our entire product range.