Dispositivo de alívio de pressão do transformador – PRD Safety Valve System
Automatic Overpressure Protection | Explosion Prevention | Fast-Acting Relief Valve | Fornecimento direto da fábrica

Responds within milliseconds
No manual intervention required
All-climate operation capability
50kVA to 10MVA+ transformers
What Is a Transformer Pressure Relief Device?
UM dispositivo de alívio de pressão do transformador (PRD) is a critical safety component that prevents catastrophic transformer tank rupture by automatically venting excessive internal pressure. When internal faults generate rapid gas expansion or oil vaporization, the PRD opens instantly to release pressure buildup, protecting the transformer tank from explosive failure.
Also known as a válvula de segurança do transformador ou válvula de alívio de pressão, this device acts as the last line of defense against transformer explosions caused by internal arcing faults, quebra de isolamento, or thermal overload conditions.
Why PRDs Are Essential
Internal transformer faults can generate pressure rises exceeding 100 psi within seconds. Without proper pressure relief, this buildup causes violent tank rupture, oil fires, and severe equipment damage. Transformer explosion prevention devices fornecer:
- Segurança Pessoal: Prevents dangerous tank explosions near personnel and facilities
- Proteção de Equipamentos: Safeguards expensive transformer assets from catastrophic structural damage
- Prevenção de Incêndios: Controlled venting reduces risk of ignition and oil fires
- Insurance Compliance: Required by most electrical codes and insurance policies
Especificações Técnicas
Common models of pressure relief valves are displayed. Please contact us for more information
| Modelo | Capacidade do transformador | Operating Pressure | Connection Size |
|---|---|---|---|
| PRD-50 | 50-315 kVA | 7-10 psi | DN50 |
| PRD-80 | 315-1000 kVA | 7-10 psi | DN80 |
| PRD-100 | 1-3.15 AMIU | 7-10 psi | DN100 |
| PRD-150 | 3.15-10 AMIU | 7-10 psi | DN150 |
Standard Features
- Material: Stainless steel construction
- Tempo de resposta: Menor que 30 milissegundos
- Reset Type: Automático (spring-loaded)
- Temperatura operacional: -40°C to +90°C
- Selagem: Viton/EPDM gaskets
- Montagem: Flange or threaded connection
- Classificação de proteção: IP65
- Padrões: CEI 60076, IEEE C57.12.00
How PRDs Work
O transformer overpressure protection system uses a spring-loaded diaphragm or disc mechanism calibrated to open at predetermined pressure thresholds (tipicamente 7-10 psi). When internal pressure exceeds this setpoint:
- Excessive pressure overcomes spring force, lifting the relief disc
- Pressurized gas and oil vapor vent rapidly through discharge ports
- Pressure drops below threshold; spring force reseats the disc automatically
- Optional contact switches signal SCADA systems when activation occurs
PRD Operating Principle
Normal Condition
PRD Housing
Relief Disc
Spring Force
Normal Pressure
Overpressure Event
Disc Lifted
Gas Venting
HIGH PRESSURE
Pressure Force
Fault Occurs
Operation Sequence
1. Operação normal:
Spring force keeps relief disc sealed against normal pressure (0-6 psi)
2. Detecção de falhas:
Internal fault creates rapid pressure rise (7-10+ psi)
3. Automatic Relief:
Disc lifts, venting gas/vapor in milliseconds
4. Auto-Reset:
Spring reseats disc when pressure normalizes
Diretrizes de instalação
Important Safety Notice
PRD installation must be performed by qualified transformer technicians following manufacturer specifications and local electrical codes. Improper installation can compromise transformer safety.
- Mounting Position: Install vertically on transformer cover to ensure proper venting direction away from personnel and equipment
- Requisitos de liberação: Maintain minimum 3-foot radius clear zone around discharge path
- Torque Specifications: Follow manufacturer torque values for flange bolts to prevent oil leaks
- Conexões Elétricas: Wire optional alarm contacts to monitoring systems using shielded cable
- Teste: Never test PRD operation while mounted on energized transformer
Aplicações
Nosso transformer pressure relief valves proteger:
- Transformadores de distribuição (50kVA – 3.15AMIU)
- Transformadores de potência (3.15AMIU – 100AMIU+)
- Transformadores de subestação
- Generator step-up transformers
- Industrial plant transformers
- Mobile/temporary transformers
Why Choose Our PRDs?
🏭 Factory Direct Pricing
Competitive wholesale rates with volume discounts for projects requiring multiple units.
✓ Qualidade Certificada
CEI 60076 and IEEE C57.12.00 compliant. ISO 9001 manufacturing facility.
🚚 Fast Delivery
Os modelos padrão são enviados dentro 7-10 dias úteis. Global freight forwarding available.
🔧 Custom Solutions
Specialized pressure setpoints, flange configurations, and alarm contact options available.
Perguntas frequentes
How do I select the correct PRD size for my transformer?
PRD sizing is based on transformer capacity (Classificação kVA/MVA). Use PRD-50 for 50-315kVA, PRD-80 for 315-1000kVA, PRD-100 for 1-3.15MVA, and PRD-150 for 3.15-10MVA transformers. For transformers above 10MVA or special applications, contact our engineering team for custom sizing calculations.
Does the PRD require periodic replacement or maintenance?
PRDs are maintenance-free during normal operation. No entanto, after any activation (pressure relief event), the device should be inspected for seal integrity and proper reset. Replace gaskets if oil leakage is detected. We recommend visual inspection annually during transformer maintenance outages. Typical service life is 15-20 years without activation.
Can PRDs be tested without removing from the transformer?
Não. Never attempt to test PRD operation while installed on an energized or oil-filled transformer. Testing requires controlled bench conditions using specialized pressure test equipment. PRD functional verification should only be performed by qualified technicians following manufacturer procedures in a workshop environment.
Request Your PRD Quotation Today
web@fjinno.net
+86 135 9907 0393
+86 135 9907 0393
135 9907 0393
🏭 Instalação de fabricação:
Parque Industrial de Rede de Grãos Liandong U
Estrada Oeste No.12 Xingye, Fucheu, Província de Fujian, China
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