THE BUYER'S GUIDE / SELECTION
Threaded Cast Iron Fittings or Cast Bronze? Choosing a Reducing Tee: Application Fit and Specification Checks
A buyer-focused checklist for the Reducing Tee Cast Bronze Threaded Fittings from Langfang Pannext Pipe Fitting Co., Ltd. It covers material (ASTM B62 C83600 / ASTM B824 C89633), ASME B16.15 Class 125 dimensions, NPT threads to ASME B1.20.1, the listed size range from 3/4 x 1/2 x 1/2 to 1-1/2 x 1 x 1, packing quantities and test claims. It also explains why buyers searching for threaded cast iron fittings should confirm material requirements first, because this reducing tee is cast bronze, not cast iron.
Material match: the product is cast bronze (ASTM B62 UNS C83600; ASTM B824 C89633), not cast iron. Confirm your specification allows bronze.
Fitting standard and class: ASME B16.15 Class 125 dimensions.
Thread standard: NPT conforming to ASME B1.20.1.
Size combination: listed range from 3/4 x 1/2 x 1/2 to 1-1/2 x 1 x 1. Some items have no listed dimensions.
Application fit: the listed application is jointing water pipe. Check lead-content rules, since the C83600 composition includes Pb 4.6–5.2%.
Mechanical data as listed: elongation 20% minimum; tensile strength 20.0 kg/mm minimum. Confirm the unit with the supplier.
Testing and certification: the product has UL certification, 100% air testing and 100% water pressure testing.
Packaging: export-standard master cartons with inner packs of 5 per bag, plus the case quantity for each item.
Threaded Cast Iron Fittings or Cast Bronze? Choosing a Reducing Tee: Application Fit and Specification Checks
Procurement teams often start a search with a broad phrase such as threaded cast iron fittings and then narrow down to a specific shape, like a reducing tee fitting. Before you go further, check one thing first. The Reducing Tee Cast Bronze Threaded Fittings from Langfang Pannext Pipe Fitting Co., Ltd. are made of cast bronze, not cast iron. If your project specification calls for cast iron or malleable iron, this product does not meet that requirement, and you should not use it as a direct substitute without approval from the engineer of record.
If your specification allows or calls for bronze, the checks below will help you decide whether this reducing tee pipe fitting fits your application.
1. Start with your buyer constraints
Write down these points before you compare item numbers:
- Material required by the specification. Iron, bronze or another alloy.
- Fitting standard and pressure class. For example, ASME B16.15 Class 125.
- Thread standard. For example, NPT.
- Run and branch sizes. All three ends of the tee.
- Service medium. The confirmed application for this product is jointing water pipe.
- Required documents. Certificates, material test reports and test records your project or market needs.
2. Material: cast bronze, not threaded cast iron fittings
The product listing gives the material as ASTM B62, UNS Alloy C83600; ASTM B824 C89633, made by casting. A related Pannext bronze plug listing gives this C83600 composition range: Cu 84.6–85.5%, Zn 4.7–5.3%, Pb 4.6–5.2%, Sn 4.7–5.1%.
The C83600 range includes lead. If your market or application limits lead content (for example, in potable water systems), confirm which listed alloy applies to your order and whether it meets your local rules. Do not assume compliance from the listing alone.
3. Dimensions, pressure class and threads
The listing gives:
- Fitting dimensions: ASME B16.15 Class 125 (written as "ASEM B16.15" in the source listing)
- Threads: NPT, conforming to ASME B1.20.1
- Elongation: 20% minimum
- Tensile strength: 20.0 kg/mm (minimum), as written in the listing. Confirm the unit with the supplier before using this figure in a submittal.
- Brand mark: "P"
- Origin: Thailand
The class for this reducing tee is Class 125. Do not select it for Class 300 duty.
4. Confirm the size combination (reducing tee threaded sizes)
Sizes are given in inches. Dimensions A, B and C are shown in the listing, but the excerpt does not state their unit, so confirm against the supplier drawing. An asterisk (*) means the listing gives no dimension for that item.
| Item No. | Size (inch) | A | B | C | Master case qty | Inner pack |
|---|---|---|---|---|---|---|
| RT3070505 | 3/4 x 1/2 x 1/2 | 1.08 | 1.38 | 1.38 | 100 | 5/bag |
| RT3070507 | 3/4 x 1/2 x 3/4 | 1.39 | 1.38 | 1.39 | 100 | 5/bag |
| RT3100505 | 1 x 1/2 x 1/2 | 1.31 | 1.22 | 1.31 | 50 | 5/bag |
| RT3100507 | 1 x 1/2 x 3/4 | 1.30 | 1.38 | 1.31 | 50 | 5/bag |
| RT3100510 | 1 x 1/2 x 1 | 1.43 | 1.24 | 1.43 | 50 | 5/bag |
| RT3100705 | 1 x 3/4 x 1/2 | 1.20 | 1.08 | 1.24 | 50 | 5/bag |
| RT3100707 | 1 x 3/4 x 3/4 | 1.30 | 1.08 | 1.31 | 50 | 5/bag |
| RT3100710 | 1 x 3/4 x 1 | 1.50 | 1.45 | 1.50 | 50 | 5/bag |
| RT3120512 | 1-1/4 x 1/2 x 1-1/4 | 1.69 | 1.40 | 1.69 | 45 | 5/bag |
| RT3120705 | 1-1/4 x 3/4 x 1/2 | * | * | * | 30 | 5/bag |
| RT3120707 | 1-1/4 x 3/4 x 3/4 | * | * | * | 30 | 5/bag |
| RT3120712 | 1-1/4 x 3/4 x 1-1/4 | 1.69 | 1.48 | 1.69 | 45 | 5/bag |
| RT3121010 | 1-1/4 x 1 x 1 | 1.52 | 1.43 | 1.60 | 35 | 5/bag |
| RT3121012 | 1-1/4 x 1 x 1-1/4 | 1.69 | 1.60 | 1.69 | 35 | 5/bag |
| RT3150515 | 1-1/2 x 1/2 x 1-1/2 | 1.84 | 1.52 | 1.84 | 30 | 5/bag |
| RT3150715 | 1-1/2 x 3/4 x 1-1/2 | * | * | * | 20 | 5/bag |
| RT3151010 | 1-1/2 x 1 x 1 | * | * | * | 35 | 5/bag |
The listed range runs from 3/4 x 1/2 x 1/2 to 1-1/2 x 1 x 1.
5. Choose the right fitting shape
- Reducing tee: use it when the branch, or one run end, is a different size from the main run.
- Equal tee: if all three ends are the same size, Pannext also lists a Cast Bronze Threaded Equal Tee Fitting. The listing gives the same material, ASME B16.15 Class 125 dimension and NPT thread data.
- Reducing coupling: if you only need an inline size change with no branch, the Reducing Coupling Cast Bronze Threaded Fitting comes in sizes from 1/4 x 1/8 upward.
6. Testing and certification claims to verify
The product description says the reducing tee is UL certified, 100% air tested, and has independent lab verification of chemical and physical properties. The quality-control section of the same listing describes 100% water pressure testing to check for leaks, along with raw material, molding, casting appearance, grinding and thread gauge checks.
Because the listing mentions both air and water testing, ask which test applies to your order and request the records. For UL or any other certification, ask for the certificate or listing number covering the exact item numbers and confirm it is valid in your target market. This article does not confirm pressure ratings beyond the stated class, and it makes no claims about price, lead time or availability.
7. Packaging
The listing describes export-standard packing: master cartons with inner boxes, and master cartons made of 5-layer corrugated paper. Case quantities for each item are shown in the table above. These help with order rounding and warehouse planning.
When this recommendation does not apply
- Your specification requires threaded cast iron fittings or malleable iron fittings.
- You need a pressure class other than Class 125, or a thread standard other than NPT.
- Your service is not water pipe jointing, and no supplier confirmation covers it.
- Local regulations restrict the lead content allowed by the listed alloy.
For documents, drawings and order details, contact Langfang Pannext Pipe Fitting Co., Ltd. with your item numbers and application data.
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Langfang Pannext Pipe Fitting Co., Ltd.
Langfang Pannext Pipe Fitting Co., Ltd. is a Sino-US joint venture, which is specialized in the production of malleable iron pipe fittings and bronze pipe fittings. PanNext has been founded in 1993 with over 366,000 square feet of facility area. It is located in Langfang City, Hebei Province - known as the Pearl on the Beijing-Tianjin Corridor,which is very convenient by land, sea and air transportation. With +30years’ R&D experiences,there are more than 350 employees working in PanNext.…
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Post time: Oct-22-2026
