When choosing a new ball valve, one of the first decisions is how to terminate the end connections. Should you go with a flanged or threaded design? The method you select can significantly impact installation, maintenance, performance and overall costs.
Both options have their advantages depending on the application. But they are not interchangeable. It’s critical to understand the key distinctions to make the optimal choice for your piping system. Let’s compare the two.
Flange Ball Valve
As the name implies, a flange end ball valve utilizes a flanged end connection instead of threaded piping. The valve body has protruding hub collars with an integral flange on each end. This ball valve flange type contains a circular pattern of bolt holes.
To install, the flange faces are bolted and gasketed together on adjoining pieces of equipment or pipe flanges. This creates a rigid, straight pipe run without threaded joints.
The dimensional standards from organizations like ANSI, ASME, JIS and others define precise measurements for flange diameters, bolt patterns/counts, pressure ratings and facing types to ensure compatibility.
Advantages:
- Allow easy removal for maintenance or replacement without cutting the pipe
- Create a straight-line installation ideal for multi-plane piping configurations
- Have a solid, blowout-proof design rated for higher pressures
- Are available in a wide range of metallurgies for any service
- Provide a leak-tight seal when properly tightened
Disadvantages:
- More labor-intensive installation and gasket replacement
- Generally more expensive than threaded valves
Threaded Ball Valves
On the other hand, threaded ball valves have tapered or straight threads machined directly into the valve end connections. These mate with corresponding threaded fittings on the pipe ends.
NPT (National Pipe Taper) is one of the most common thread forms. The tapered thread design allows an interference fit to create a pressure seal. Threaded joints require no additional gaskets or hardware.
Advantages:
- Quick, low-cost installation with basic tools
- More compact form factor versus flanges
- Disassembly is simple by unscrewing union fittings
- Generally lower-cost than flanged valves
Disadvantages:
- Weaker than flanges and prone to stripping or cross-threading
- Less blowout-proof – mainly limited to lower pressure services
- Metallurgy options tend to be more limited
- Installation requires cutting pipe runs for tight spaces
Flanged vs Threaded – Which Style is Better?
There is no universal “better” choice – it depends on the specific application requirements. In general:
- Threaded connection works well for low-pressure utility services like air, water, inert gas lines
- Flanged is preferred for critical, hazardous, high-pressure and high-temperature services
- Flanges are used where frequent maintenance is required with easy removal
- Threaded suits permanent, rigid installations in tight spaces
Many facilities utilize a mix of both threaded and flanged ball valves based on their piping system needs.
Abschluss
Whether you opt for flanged or threaded ball valves, ensure they are sourced from a trusted manufacturer that adheres to published standards. This guarantees compatibility and optimal performance.
Xintai Valve Company produces a wide range of both flanged and threaded end ball valves to global quality specifications. Our experts can guide your selection based on your operating conditions and requirements. Don’t compromise your piping system integrity – consult with Xintai on your next ball valve purchase.
