PP Flanged Diaphragm Valve | Polypropylene | EPDM PTFE Diaphragm | DN15–DN150 | Chemical Supplier India

Description

PP Flanged Diaphragm Valve Supplier India | Polypropylene | EPDM / PTFE Diaphragm | Weir & Straight-Through | DN15–DN150 | KELOR

Supplier: Krishna Industries (KELOR) – Ahmedabad, Gujarat, India
Established: 2017 | GSTIN: 24AKLPP6499B1ZT | IEC: AKLPP6499B
MOQ: 10 Nos | Body: Polypropylene (PP) | Standard: ISO 16135 / DIN 3356
Sizes: DN15–DN150 | Rating: PN10 (at 20°C — derated at higher temperature)

PP Flanged Diaphragm Valve Supplier in India

Krishna Industries (KELOR), based in Ahmedabad, Gujarat, is a B2B supplier of PP Flanged Diaphragm Valves — Polypropylene (PP) body — EPDM, PTFE, and PTFE-backed EPDM diaphragm — weir type and straight-through type — flanged end DIN/EN PN10 — DN15 to DN150 — handwheel manual and pneumatic actuated — ISO 16135 / DIN 3356 — GST invoice — MOQ 10 Nos — Pan India dispatch from Ahmedabad.

The PP diaphragm valve is the correct valve for corrosive chemical, acid, alkali, effluent, and aggressive fluid service where metal valves would corrode, contaminate the process, or require expensive alloy upgrades. The Polypropylene body provides excellent resistance to most mineral acids, alkalis, and salt solutions at moderate temperatures. The flexible diaphragm seals against the body weir or seat — no stem penetration into the flow path — inherently leak-free stem seal, suitable for toxic and hazardous chemical service. Used extensively in Gujarat’s chemical belt (Ankleshwar, Vapi, Dahej, Bharuch), Indian ETP/STP contractors, electroplating shops, textile dyeing units, and pharmaceutical plants.

Weir Type vs Straight-Through — Critical Design Difference

Standard supply: Weir type is standard unless straight-through is specifically requested. Confirm valve type in RFQ for slurry or solids-containing media.

Thermoplastic Body Material Comparison

For most Indian chemical plant applications at temperatures below 60°C — dilute HCl, dilute H2SO4, NaOH, ferric chloride, copper sulphate, chromic acid solutions, textile dyes, ETP chemicals — PP flanged diaphragm valve is the correct and most economical specification. Upgrade to PVDF only when media or temperature exceeds PP limits.

PP Chemical Compatibility — Common Indian Chemical Plant Media

Compatibility guide is indicative. Always confirm media, concentration, and temperature with Krishna Industries before finalising order. Actual compatibility depends on chemical concentration, temperature, and mixture effects.

PP Pressure-Temperature Derating

Polypropylene loses mechanical strength at elevated temperature — the pressure rating of a PP valve must be derated above 20°C. This is critical for Indian chemical plant applications where process temperatures may be 40°C to 70°C.

Important: Always state operating temperature AND operating pressure in your RFQ — not just one. A PP valve rated PN10 at 20°C may only be suitable for PN3 at 70°C. For hot chemical service above 60°C, consider CPVC or PVDF body instead of PP.

Technical Specifications

Diaphragm Material Selection Guide

Applications in Indian Industries

• Gujarat chemical belt (Ankleshwar, Vapi, Dahej, Bharuch) — PP PTFE-backed EPDM — acid dosing lines, chemical transfer, reactor feed and discharge, neutralisation tank — DN25 to DN100 most common
• Effluent treatment plants (ETP) — PP EPDM weir type — chemical dosing (acid/alkali for pH correction), ferric chloride dosing, polymer dosing — DN15 to DN80
• Electroplating and surface treatment — PP PTFE — chromic acid, ferric chloride, copper sulphate, nickel sulphate circulation lines — flanged PN10 for plating tank connections
• Textile dyeing units (Surat, Ahmedabad) — PP EPDM — dye chemical lines, bleaching agent (NaOCl) distribution, caustic soda transfer
• Pharmaceutical plants — PP or PVDF PTFE — purified water chemical dosing, acid/alkali neutralisation, ETP chemical feed
• Fertiliser plants — PP PTFE-backed EPDM — phosphoric acid, sulphuric acid, ammonia handling
• Water treatment and chlorination — PP PTFE — chlorine dosing, fluoride dosing, alum dosing — chemical resistant, no contamination of treated water
• Swimming pool chemical dosing — PP EPDM — chlorine and pH adjustment chemical lines

Frequently Asked Questions

1. What is the difference between weir type and straight-through diaphragm valve?

Weir type has a raised saddle across the bore — the diaphragm presses onto this weir to close. Shorter diaphragm travel means lower torque and longer diaphragm life. Straight-through has a flat bore — the diaphragm must travel the full bore diameter. Weir type is correct for clean chemical, acid, alkali, and water service — the most common specification. Straight-through is specified for slurry, fibrous media, and where complete bore drainage is required.

2. Can PP diaphragm valve handle concentrated sulphuric acid?

PP body handles sulphuric acid up to approximately 70% concentration at moderate temperature. Above 70% concentration (concentrated H2SO4), PP body is not recommended — specify PVDF body with PTFE diaphragm. Always state acid concentration AND temperature in your RFQ. For dilute H2SO4 up to 50% at temperatures below 50°C — PP PTFE-backed EPDM diaphragm is the standard specification in Indian chemical plants.

3. Why does pressure rating decrease at higher temperature?

Polypropylene is a thermoplastic — its mechanical strength (yield stress) decreases as temperature increases. At 20°C a PP valve is rated PN10 (10 bar). At 60°C, the same valve should only be used up to approximately 4.5 bar. Exceeding the derated pressure at operating temperature will cause body deformation or failure. Always confirm operating temperature AND pressure when ordering — not just one of the two.

4. EPDM or PTFE diaphragm — which is standard?

EPDM is standard supply — suitable for water, dilute acid, dilute alkali, and most ETP service. PTFE (or PTFE-backed EPDM) is specified when the media attacks EPDM — concentrated acids, oxidising chemicals, chlorinated water above 200ppm, solvents. PTFE-backed EPDM (sandwich diaphragm) gives PTFE chemical resistance with better flexibility and cycle life than plain PTFE — recommended for chemical plant service where EPDM is borderline.

5. Can the diaphragm be replaced without removing the valve from the pipeline?

Yes — the top bonnet unbolts from the body, the compressor and old diaphragm are removed, and a new diaphragm drops in. The valve body stays bolted in the pipeline. Diaphragm replacement is a standard maintenance activity taking 15–20 minutes with basic tools. Keep one set of spare diaphragms per valve size on site for planned maintenance.

6. Is UV stabilised PP available for outdoor installation?

Standard PP can degrade with prolonged UV exposure — surface chalking and embrittlement over 2–3 years of outdoor use. For outdoor installation, specify UV-stabilised (carbon black compounded) PP body — available on request. Alternatively, paint or cover the valve body. Diaphragm should be protected from direct sunlight regardless of UV stabilisation.

7. What is the MOQ?

MOQ is 10 Nos. Project orders for ETP, chemical plant, or electroplating shop — 20 to 200+ Nos across sizes — handled with project pricing and consolidated dispatch from Ahmedabad.

Conclusion

The PP Flanged Diaphragm Valve supplied by Krishna Industries (KELOR) is the correct non-metallic valve for corrosive chemical, acid, alkali, effluent, electroplating, textile, and pharmaceutical service in India — Polypropylene body — EPDM, PTFE, PTFE-backed EPDM diaphragm — weir type and straight-through — flanged DIN/EN PN10 — DN15 to DN150 — handwheel manual and pneumatic actuated — ISO 16135 / DIN 3356. Confirm media, concentration, and operating temperature in RFQ for correct diaphragm material recommendation. GST invoice, Pan India dispatch from Ahmedabad. WhatsApp valve type, size, diaphragm material, and quantity for bulk pricing within 2 hours.