ASC
300# Extra Heavy Black Malleable Iron Union
- Availability:
- Usually in Stock – Ships Quickly
- Weight:
- 0.00 LBS
Description
300# Extra Heavy Black Malleable Iron Union
300# extra heavy black malleable iron unions provide a removable threaded connection between two compatible male-threaded pipes, pipe nipples, valves, or fittings. The female NPT connections and three-piece union design allow the piping system to be separated for maintenance, repair, replacement, or modification without cutting or rotating the connected pipe.
Select the required nominal pipe size from the product options above. The selected variation determines the ASC item number, online selling price, estimated weight, net cost, and other size-specific product information.
Product Highlights
- 300# / Class 300 extra heavy black malleable iron construction
- Female NPT threaded connections on both ends
- Three-piece union design provides a removable piping connection
- Allows connected piping to be separated without cutting the pipe
- Designed for maintenance, repair, replacement, and system modification
- Manufactured to ASME B16.3 requirements
- Threads conform to ASME B1.20.1
- Malleable iron material conforms to ASTM A197
- UL Listed
- ASC Figure 3459
- Available in nominal pipe sizes from 1/4" through 4"
Technical Specifications
| Material | Black Malleable Iron |
|---|---|
| Pressure Class | 300# / Class 300 / Extra Heavy |
| Connection | Female NPT x Female NPT |
| Fitting Type | Threaded Union |
| Function | Removable Threaded Piping Connection |
| Thread Standard | ASME B1.20.1 |
| Dimensional Standard | ASME B16.3 |
| Material Standard | ASTM A197 |
| Finish | Black |
| Listing | UL Listed |
| Manufacturer | ASC |
| Figure Number | 3459 |
| Available Sizes | 1/4" through 4" |
How a Threaded Union Works
A threaded union consists of two female-threaded end pieces joined by a center union nut. Each end threads onto a compatible male-threaded pipe, pipe nipple, valve, or fitting. Tightening the union nut draws the two halves together to complete the connection. Loosening the center nut allows the piping sections to be separated without cutting the pipe or rotating the connected components.
Common Applications
Commercial and Mechanical Systems
- Mechanical-room piping
- Equipment and valve connections
- Water and utility piping
- Compressed-air systems
- Pump and equipment service connections
- General repair and maintenance
Industrial and Fire-Protection Service
- Industrial process piping
- Fire-protection piping where approved
- Oil and petroleum piping
- Compatible gas service
- Approved steam service
- Locations requiring future piping disconnection
Product Resources
Review the ASC malleable iron threaded fittings catalog for dimensions, weights, standards, and additional product information before installation.
Need Help Selecting a 300# Black Malleable Iron Union?
Our industrial PVF specialists can help confirm the required pipe size, pressure class, thread type, material compatibility, service conditions, and product availability.
Frequently Asked Questions
What is a 300# black malleable iron union used for?
It creates a removable threaded connection between two compatible male-threaded piping components so the line can be separated for maintenance, repair, replacement, or modification.
Does this union have female threads on both ends?
Yes. ASC Figure 3459 has female NPT threaded connections on both ends.
Can the piping be disconnected without cutting the pipe?
Yes. Loosening the center union nut allows the connected piping sections to be separated without cutting the pipe or rotating the connected components.
What pressure class is this fitting?
This fitting is manufactured as a 300# / Class 300 extra heavy threaded malleable iron fitting.
What sizes are available?
Available product variations range from 1/4" through 4" nominal pipe size.
What standards and listings apply?
The fitting conforms to ASME B16.3, ASTM A197, and ASME B1.20.1 requirements. ASC lists its Class 300 malleable iron fittings as UL Listed.
Should thread sealant be used during installation?
Use an approved pipe-thread sealant or thread tape selected for the piping media, pressure, temperature, applicable codes, and manufacturer recommendations.
Important Ordering Notes
- Select the required nominal pipe size before adding the product to your cart.
- This union has female NPT threaded connections on both ends.
- The selected variation determines the ASC item number, online selling price, estimated weight, and net cost.
- Confirm the nominal size and thread type of both mating components before ordering.
- Confirm that a threaded union is appropriate for the required service and installation location.
- Confirm pressure, temperature, media compatibility, and application requirements before installation.
- Use an approved thread sealant suitable for the piping media and operating conditions.
- Install the union where the center nut remains accessible for future service.
- Depressurize and drain the piping system before loosening or removing an installed union.
- Support connected piping properly to avoid excessive mechanical stress on the fitting.
- Installation should be completed by qualified personnel and comply with applicable codes and standards.
