1. PVC Flange Fundamentals and Classification
In chemical anti-corrosion piping, electroplating fluid transport and wastewater systems, PVC flanges are key components connecting pipes to valves and equipment. A complete PVC flange specifications and dimensions chart must cover four elements: nominal size range, pressure rating, connection type, and execution standard. PVC flanges fall into four main structural types:
- Flat welding flange (plate flat): most common; pipe end inserts into the flange bore and is double welded; for PN6-PN10 low-pressure systems
- Butt-welding flange (welding neck): butt-welded to pipe end, high strength and even stress distribution; for PN16 medium-pressure systems
- Blind flange (flange cover): closes pipe ends or isolates during maintenance; removable
- Loose flange (lap joint): rotatable flange for easy hole alignment; often paired with stub ends
By material, UPVC (rigid PVC) and CPVC (chlorinated PVC) are most common in industrial piping. UPVC handles up to 60°C, CPVC up to 95°C; selection must consider media temperature.
2. PVC Flange Specifications and Dimensions Chart (DN15-DN300)
2.1 PN10 Flat Welding Flange Dimensions (GB/T 9113)
Below is the complete dimension table for the most common UPVC PN10 flat welding flanges (mm):
| Nominal DN | Outer D | Bore d | Thickness C | Holes n | Hole dia K | Bolt circle P | Bolt |
|---|---|---|---|---|---|---|---|
| DN15 | 95 | 20 | 14 | 4 | 14 | 65 | M12 |
| DN20 | 105 | 25 | 16 | 4 | 14 | 75 | M12 |
| DN25 | 115 | 32 | 16 | 4 | 14 | 85 | M12 |
| DN32 | 140 | 38 | 18 | 4 | 18 | 100 | M16 |
| DN40 | 150 | 45 | 18 | 4 | 18 | 110 | M16 |
| DN50 | 165 | 57 | 20 | 4 | 18 | 125 | M16 |
| DN65 | 185 | 76 | 20 | 4 | 18 | 145 | M16 |
| DN80 | 200 | 89 | 22 | 8 | 18 | 160 | M16 |
| DN100 | 220 | 108 | 22 | 8 | 18 | 180 | M16 |
| DN125 | 250 | 133 | 24 | 8 | 18 | 210 | M16 |
| DN150 | 285 | 159 | 24 | 8 | 22 | 240 | M20 |
| DN200 | 340 | 219 | 26 | 8 | 22 | 295 | M20 |
| DN250 | 395 | 273 | 28 | 12 | 22 | 350 | M20 |
| DN300 | 445 | 325 | 30 | 12 | 22 | 400 | M20 |
2.2 PN16 Flat Welding Flange Dimensions (selected sizes)
Higher PN16 rating means larger outer diameter and thickness:
| Nominal DN | Outer D | Thickness C | Holes n | Bolt circle P |
|---|---|---|---|---|
| DN50 | 165 | 22 | 4 | 125 |
| DN80 | 200 | 24 | 8 | 160 |
| DN100 | 220 | 24 | 8 | 180 |
| DN150 | 300 | 28 | 8 | 250 |
| DN200 | 360 | 30 | 12 | 310 |
| DN250 | 425 | 34 | 12 | 370 |
| DN300 | 485 | 38 | 16 | 430 |
2.3 Blind Flange Dimensions
Blind flanges share the sealing face dimensions of the same-size flat welding flange but increase thickness by 2-4mm to handle internal pressure: DN100 thickness 26mm, DN150 28mm, DN200 32mm.
3. Standards and Pressure Ratings
3.1 Main Standards
- GB/T 9113-2010: national standard for steel pipe flanges, PVC flanges may reference dimensions
- HG/T 20538-2020: chemical rigid PVC pipe flange standard
- GB/T 4219.1-2008: rigid PVC pipe standard
- ISO 7005-1: international metal flange standard (PVC reference)
- DIN 2501 / EN 1092: European standards, common for imported equipment
3.2 Pressure Rating Comparison
| Rating | Working pressure (MPa) | Temp limit | Typical use |
|---|---|---|---|
| PN6 | 0.6 | ≤60°C | Drainage, low-corrosion media |
| PN10 | 1.0 | ≤60°C | Chemical water, electroplating fluid |
| PN16 | 1.6 | ≤60°C | High-pressure chemicals, compressed gas |
CPVC flanges can work up to 95°C; PN10 still holds 0.6 MPa at 80°C. See /products/engineering_plastic.
4. PVC Flange Selection Tips
- Confirm media and temperature: choose UPVC or CPVC based on media and max temperature
- Determine working pressure: select PN rating at 1.5x working pressure
- Verify flange type: flat for low pressure, butt-weld for medium, loose for maintenance locations
- Check bolt hole count and diameter: must match the mating flange exactly
- Inspect sealing face: flat face (FF) most common; male-female (MF) seals better
- Matched gaskets: PVC flanges pair with EPDM or FKM gaskets; asbestos prohibited
- Batch consistency: use the same manufacturer and batch within one piping system
5. PVC Flange Price Reference
Common domestic UPVC flange quotes (for reference):
| Size | PN10 flat (RMB/pc) | PN16 flat (RMB/pc) | Blind (RMB/pc) |
|---|---|---|---|
| DN50 | 12-22 | 18-30 | 18-28 |
| DN80 | 22-38 | 32-50 | 32-48 |
| DN100 | 30-52 | 45-70 | 45-65 |
| DN150 | 65-110 | 95-150 | 95-140 |
| DN200 | 120-200 | 175-280 | 175-260 |
| DN300 | 280-450 | 420-620 | 420-580 |
CPVC flanges typically cost 1.5-2x UPVC. Imports (AGRU, SPEARS) are 2-3x domestic.
As a professional engineering plastics supplier, huagong offers one-stop procurement of multi-spec, multi-brand PVC flanges and fittings, with selection advice and full kits (flange, gasket, bolts). Contact us for quotations.
6. FAQ
Q1: PVC vs. PPH flanges—which is more corrosion resistant?
UPVC resists acids and alkalis well but not aromatic solvents; PPH offers broader chemical resistance, especially to salt solutions and dilute acids. For hot hydrochloric acid, PPH or PVDF flanges are recommended; for ambient dilute acid/alkali, UPVC delivers the best value.
Q2: How much pressure can PVC flanges handle?
PN10 UPVC flanges hold 1.0 MPa at ambient; PN16 holds 1.6 MPa. Capacity drops with temperature—about 60% at 60°C. See /blog/pvc-pipe-specifications-chart for the temperature-pressure curve.
Q3: How to connect PVC flanges to steel pipe?
Match same size and PN rating, both with flat face (FF) sealing, insert an EPDM flat gasket between, and tighten bolts diagonally to specified torque.
Q4: What standard do PVC flanges follow?
Chemical systems use HG/T 20538-2020; general piping references GB/T 9113. Imported equipment often follows DIN 2501 or EN 1092. The standard should be specified in the purchase contract.
Q5: How to choose bolts for PVC flanges?
304 stainless bolts work in dry ambient environments; 316L stainless or titanium for humid or corrosive environments; FRP/PP bolts for severely corrosive conditions. Bolt size must match the hole diameter to avoid under-loading.
7. Summary and Action
The PVC flange specifications and dimensions chart is the core reference for chemical anti-corrosion piping design and procurement. Selection must start with media, temperature and pressure, then verify flange type, standard and bolt parameters, with gaskets and bolts procured together to avoid field issues.
For the complete PVC flange specifications chart PDF, 3D models or bulk pricing, contact huagong—our engineering plastics team provides professional flange selection and piping system support.
Related:
- Browse the Engineering Plastics Center for PVC pipe and fitting specs
- Read PVC Pipe Specifications Chart for pipe-flange matching
- Contact huagong for complete flange, gasket and bolt kits