ZBWA42Y-16/25/40 C/P/R Bellows Back Pressure Balanced Full Lift Safety Valve
Bellows Back Pressure Balanced Full Lift Safety Valve for process pipelines and equipment where variable back pressure or hazardous/corrosive media require bellows isolation. Key selection data include DN20-DN350, with outlet size larger than inlet on full-lift designs per catalog table, PN16, PN25 and PN40, Up to 300 deg C, materials, connection standard and set pressure.
Final set pressure, certified relieving capacity, material code and connection standard must be confirmed on the approved datasheet before purchase.
- Size range: DN20-DN350, with outlet size larger than inlet on full-lift designs per catalog table
- Pressure rating: PN16, PN25 and PN40
- Temperature: Up to 300 deg C
- Connection: Flanged inlet and outlet
- Media: Poisonous, flammable or corrosive media, and service with variable back pressure
- Drawings, test records and material documents confirmed for the ordered configuration.
Technical Specifications and Selection Data
Product Model
ZBWA42Y-16/25/40 C/P/R
Size Range
DN20-DN350, with outlet size larger than inlet on full-lift designs per catalog table
Pressure Rating
PN16, PN25 and PN40
Temperature Range
Up to 300 deg C
Applicable Media
Poisonous, flammable or corrosive media, and service with variable back pressure
Connection Type
Flanged inlet and outlet
Standards and Compliance
GB/T 12241, GB/T 12242 and GB/T 12243 for safety valve design, performance and test references; model coding follows the JB/T 308 valve model method where applicable.
Engineering Insight: Model Logic and Application Boundary
Model code: WA42Y = bellows balanced A42Y full-lift safety valve; W indicates bellows; C/P/R identify body material code.
Typical application: process pipelines and equipment where variable back pressure or hazardous/corrosive media require bellows isolation
Capacity review: Main connection dimensions are listed on the source catalog page. Discharge capacity and orifice sizing should be confirmed by set pressure, medium, temperature and applicable code.
This product family should not be selected from model code, nominal size or pressure class alone. Confirm the relieving scenario, required capacity, set pressure, operating margin, temperature, back pressure and actual connection standard.
Dimensions and Selection Guide
The table below is transcribed from catalog page 30. Verify critical dimensions against the approved order drawing before fabrication or piping release.
| Nominal Diameter (DN) | do | Nominal Diameter (DN) | L | L1 | Approx. H |
|---|---|---|---|---|---|
| 20 25 32 40 50 | 15 | 25 | 110 | 95 | 281 |
| 20 25 32 40 50 | 16 | 32 | 110 | 95 | 281 |
| 20 25 32 40 50 | 20 | 40 | 1 15 | 100 | 285 |
| 20 25 32 40 50 | 25 | 50 | 120 | 1 1 0 | 295 |
| 20 25 32 40 50 | 32 | 65 | 135 | 120 | 305 |
| 65 100 125 150 | 40 | 80 | 160 | 140 | 394 |
| 65 100 125 150 | 50 | 100 | 170 | 135 | 406 |
| 65 100 125 150 | 65 | 125 | 205 | 160 | 511 |
| 65 100 125 150 | 80 | 150 | 210 | 190 | 586 |
| 65 100 125 150 | 100 | 175 | 255 | 230 | 601 |
| 200 250 300 350 | 125 | 250 | 305 | 260 | 734 |
| 200 250 300 350 | 150 | 300 | 350 | 320 | 928 |
| 200 250 300 350 | 200 | 400 | 370 | 350 | 1159 |
| 200 250 300 350 | 250 | 500 | 375 | 415 | 1314 |
RFQ checklist
RFQ checklist: model or valve type, DN/NPS, PN/Class, set pressure, relieving medium, operating temperature, body and trim material, inlet/outlet connection standard, cap/lever/pilot options, quantity, drawing, certificate and inspection requirements.
Failure Analysis, Manufacturing Evidence and Quality Control
Common misapplication risks: incorrect thread or connection standard, insufficient certified relieving capacity, unsuitable body or trim material, operating pressure too close to set pressure, unreviewed back pressure, and installation loads transferred to the valve.
Material review: body materials: WCB, CF8, CF8M or CF3M according to C/P/R/RL-style material requirements. Trim and internals: Stainless or corrosion-resistant trim with bellows isolation, selected by service. Spring and stem: 50CrVA spring for standard service; stainless or coated fluoroplastic/304 spring options for corrosive service where specified.
Testing and inspection: Set pressure calibration, shell strength test, seat tightness/leakage test, reseating/blowdown check, dimensional inspection and material verification can be supplied according to the confirmed standard and order requirements.
Source and scope: product data is based on Zobai Safety Valve Product Catalog.pdf, catalog page 30. Project compliance remains subject to the approved datasheet, drawing, calculation and controlled certificates for the ordered configuration.
Review material traceability, type-test scope and project certificate requirements.
Related Products
FAQ
Safety Valve FAQs
What models are covered by this ZBWA42Y-16/25/40 C/P/R Bellows Back Pressure Balanced Full Lift Safety Valve page?
ZBWA42Y-16/25/40 C/P/R
What size, pressure and temperature data should be confirmed?
Size: DN20-DN350, with outlet size larger than inlet on full-lift designs per catalog table. Pressure: PN16, PN25 and PN40. Temperature: Up to 300 deg C. Confirm the exact combination for the selected model.
Which media can this product family handle?
Poisonous, flammable or corrosive media, and service with variable back pressure. Material and sealing compatibility require review for the actual fluid composition and temperature.
Can the catalog dimension table be used for final fabrication?
Use it for preliminary review only. Confirm critical dimensions, connection details and orientation on the approved order drawing before piping or equipment fabrication.
What should be included in the RFQ?
RFQ checklist: model or valve type, DN/NPS, PN/Class, set pressure, relieving medium, operating temperature, body and trim material, inlet/outlet connection standard, cap/lever/pilot options, quantity, drawing, certificate and inspection requirements.