Confirm the valve function
A GB/T 587 stop valve is for isolation and throttling. If reverse-flow prevention is also required, check GB/T 588 stop-check valves separately.
GB/T 587 covers marine bronze flanged stop valves used for isolation and flow control in shipboard systems. This guide summarizes the specification points a buyer should confirm before inquiry: body type, size, pressure rating, materials, service medium, temperature, flange details and documentation scope.
A GB/T 587 stop valve is for isolation and throttling. If reverse-flow prevention is also required, check GB/T 588 stop-check valves separately.
The catalog lists 0.6, 1.6 and 2.5 MPa ratings, with service media including seawater, freshwater, oil and steam up to 250 °C.
Material certificate, pressure-test records, inspection and class-certificate scope are confirmed by product and order.
The table below reflects the GB/T 587-2008 catalog data used on the corresponding product page. Where your project requires a deviation, state it in the RFQ so it can be checked as a separate technical requirement.
| Item | Catalog information | Buyer action |
|---|---|---|
| Valve type | Marine bronze flanged stop valve | Confirm whether simple isolation or throttling duty is required |
| Standard | GB/T 587-2008 | State the standard and edition on the requisition |
| Body type | Type A/AS or Type B/BS | Confirm configuration, flow direction and installation space |
| Size range | DN15-50 and 15-25 by body type | Give the required size and quantity for each body type |
| Pressure rating | 0.6 / 1.6 / 2.5 MPa | Match the rating to system design pressure, not nominal pipe size alone |
| Body, bonnet and disc | Cast tin bronze ZCuSn5Pb5Zn5 | Confirm the specified casting and required material documentation |
| Stem | Aluminium bronze CuA19Mn2 | Confirm trim requirements if the project specification is stricter |
| End connection | Flanged | Confirm flange drilling, face type and face-to-face dimensions |
| Service media | Seawater, freshwater, lubricating oil, fuel oil and steam | State the actual medium and working condition |
| Temperature | Steam service up to 250 °C | Confirm maximum working temperature and cycling condition |
| Step | What to confirm | Common risk |
|---|---|---|
| 1. Function | Isolation, throttling, or stop-check duty | A stop valve cannot replace a check valve where backflow must be prevented |
| 2. Body type | Type A/AS or B/BS, flow direction and orientation | Wrong body type can affect installation and maintenance access |
| 3. Size and quantity | DN size and quantity per body type | Mixed lines can result in the wrong size being quoted |
| 4. Pressure rating | 0.6, 1.6 or 2.5 MPa requirement | Selecting by availability rather than system design pressure is unsafe |
| 5. Material | Bronze body, bonnet, disc and stem material | A material name alone does not define certificate or inspection scope |
| 6. Service conditions | Medium, temperature and application system | Seawater, oil and steam place different demands on sealing and trim |
| 7. Documents | MTC, test records, inspection and class requirements | Late certificate requirements may not match the production arrangement |
ZCuSn5Pb5Zn5 is a Chinese cast tin bronze commonly discussed alongside ASTM B62 C83600 in marine valve procurement. The comparison is useful for communication, but it is not automatic substitution approval. For a project order, the governing specification, class requirement and approved manufacturer scope decide whether an alternative material can be accepted.
| Reference | Use in selection | Caution |
|---|---|---|
| ZCuSn5Pb5Zn5 | GB/T 587 catalog material for body, bonnet and disc | Confirm casting method, marking and material documentation |
| CuA19Mn2 | Catalog stem material | Confirm trim requirements when wear or corrosion resistance is specified |
| ASTM B62 C83600 | Common communication reference for overseas buyers | Do not treat as an approved equivalent unless the buyer or specification accepts it |
| Medium | Selection check |
|---|---|
| Seawater | Confirm material, application system, installation position and maintenance expectation |
| Freshwater | Confirm pressure rating and isolation duty |
| Fuel oil and lubricating oil | Confirm temperature, sealing compatibility and cleanliness requirement |
| Steam | Confirm maximum temperature does not exceed the catalog limit of 250 °C |
| Other media | Send the medium, concentration, temperature and pressure for technical confirmation |
Subject: GB/T 587 marine bronze stop valve RFQ Standard: GB/T 587-2008 Body type: Type A/AS / Type B/BS Size and quantity: Pressure rating: 0.6 / 1.6 / 2.5 MPa Body material: ZCuSn5Pb5Zn5, or project-approved alternative Stem material: CuA19Mn2, or project requirement End connection: Flanged Flange drilling / face-to-face requirement: Service medium and maximum temperature: Classification society / certificate requirement: Material certificate and pressure-test record requirement: Destination port / delivery term: Required delivery date:
| Question | Answer |
|---|---|
| What is the difference between GB/T 587 and GB/T 588? | GB/T 587 is a flanged bronze stop valve for isolation and flow control. GB/T 588 is the corresponding stop-check valve family, so it must be considered when backflow prevention is required. |
| Can C83600 replace ZCuSn5Pb5Zn5? | Not automatically. C83600 is a useful communication reference, but substitution requires approval under the buyer's specification, class requirements and the manufacturer's scope. |
| Which pressure rating should be selected? | Select from the catalog ratings of 0.6, 1.6 and 2.5 MPa according to the system design pressure and applicable project specification. |
| What flange details should be stated? | State the required drilling standard, face type, facing finish and face-to-face dimension where the drawing or class specification imposes them. |
| What documents are confirmed? | EN 10204 3.1 MTC, pressure-test records, inspection, class certificates and marking scope are confirmed by product and order. |
This guide is for procurement communication and does not replace GB/T 587, classification-society rules, ship specification or the approved project drawing. Final selection must be confirmed against the governing technical documents.
Send the body type, size, pressure, service condition and certificate requirement. We will check the specification before quoting.