Top 5 Types of Plate Flanges for Waterworks and Valves

Choosing the right flange can make a huge difference in the effectiveness of your waterworks and valve systems. But how do you know which type suits your needs best? 

Let’s dive into the top 5 flange types, exploring their distinct features, benefits, and ideal uses to help you make an informed choice for your next project.

1. Flat Plate Flange

Flat plate flanges are commonly used in low-pressure applications requiring minimal sealing. Their straightforward design makes them cost-effective for basic waterworks systems where pressure is manageable and connections are straightforward.

• Advantages for Waterworks: Given their simplicity, flat plate flanges are highly versatile. They work well in non-corrosive environments where leaks are not a major concern. They are particularly useful for quick repairs and temporary setups, offering a basic but effective sealing mechanism when combined with gaskets.
• Best Practices for Use: It’s important to select the right gasket material for sealing efficiency. Flat plate flanges are often bolted, so proper torque is essential to prevent leakage.
• When Not to Use: Due to their limited pressure resistance, they are unsuitable for systems requiring significant sealing or high-stress operations.

2. Raised Face Plate Flange

What’s a raised face plate flange? A raised face flange is engineered with a small raised section around the bore, where the gasket is placed. This design enhances sealing under moderate to high-pressure conditions.

• Performance in Waterworks: The raised face flange design concentrates pressure on a smaller gasket area, leading to a better seal. It is an ideal choice for waterworks systems where pressure fluctuations occur, as it offers leak prevention even during varying conditions.
• Industries & Applications: Beyond waterworks, these flanges are also widely used in chemical and oil & gas industries. For valve systems that need tight seals under higher pressure, raised face flanges provide a cost-effective solution that balances sealing strength and installation ease.
• Installation & Considerations: When installing a raised face flange, pay attention to the type and thickness of the gasket. The pressure rating and temperature compatibility of the gasket must align with the flange type and the piping system.

3. Slip-On Plate Flange

Slip-on plate flanges are designed for easy sliding over the pipe. Their double-welded feature makes them highly durable, with welds both inside and outside providing additional support.

• Usage in Waterworks Systems: Slip-on plate flange type is optimal for low to moderate-pressure water systems that require a quick and reliable connection. They offer greater flexibility than flat plate flanges, providing a more secure hold while still being easier to align and install than some more complex flange types.
• Material and Pressure Compatibility: These flanges are often made from stainless steel, carbon steel, or alloys. Each material caters to different needs, from corrosion resistance in coastal waterworks to strength in high-pressure valve applications.
• Installation Insight: Ensure the pipe is properly aligned before welding. The welds must be clean and even, as the security of the slip-on flange relies on the integrity of both internal and external welds.

4. Weld Neck Plate Flange

What are weld neck plate flanges? Weld neck flanges are identified by their tapered neck, which gives the flange added strength and stability. They’re typically used in high-pressure, high-temperature environments, where their design helps distribute stress evenly between the pipe and the flange.

• Why They Matter in Waterworks: For critical waterworks applications where leaks and pipe stress can’t be risked, weld neck flanges are a top choice. Their design minimizes turbulence and erosion at the flange joints, making them highly durable.
• Industries & Best Fit: Beyond standard water systems, weld neck flanges are often found in steam piping, high-pressure gas lines, and chemical processing. They offer structural integrity that helps prevent system failures.
• Maintenance & Durability: While weld neck flanges offer superior reliability, they are more labor-intensive to install due to the need for precision welding. The flange’s material should match or be compatible with the pipe to ensure longevity and prevent corrosion or weakening at the joint.

5. Blind Plate Flange 

Blind plate flanges are solid disks used to close off the ends of pipes or valves, providing a safe way to isolate a section of the system for maintenance, testing, or repair.

• Functionality in Waterworks: Blind flanges are versatile and are often used when the system needs to be easily accessible for inspection or alterations. They can effectively block off a pipe or valve end and can be re-installed as needed without damage to the pipe.
• Testing & Isolation: These flanges are essential when conducting pressure tests on piping systems or during system upgrades. They provide a way to secure the pipeline, preventing fluid flow and ensuring safety.
• Removal & Reuse Considerations: Because they are removable and reusable, blind flanges offer cost savings for systems requiring regular maintenance. Ensure that the bolts and gaskets used are pressure-rated and compatible with the system requirements.

Benefits of Using Plate Flanges in Waterworks and Valves

Pressure Management

Plate flanges ensure secure connections in systems under various pressures, effectively managing fluid flow and preventing leaks.

Sealing Efficiency

With the right gasket and bolts, plate flanges offer effective sealing even under moderate to high-pressure environments.

Versatile Application

Whether for connecting pipes, valves, or closing off systems, plate flanges are adaptable to different requirements, including waterworks, sewage systems, and industrial plumbing.

Durability and Strength

Using high-grade materials like stainless steel or carbon steel ensures that plate flanges remain durable against corrosion, temperature changes, and fluid pressure over time.

How to Choose the Right Plate Flange

1. Assess your system’s pressure and temperature requirements to select the appropriate flange type that withstands those conditions without compromising sealing.
2. Plate flanges are available in carbon steel, stainless steel, alloy steel, and other materials. Choose one that complements your water system and is resistant to corrosion, wear, and chemical reactions.
3. Ensure that the flange’s bolt pattern aligns with the piping and valve setup. Matching the flange bore size to the pipe diameter is crucial for proper sealing and pressure containment.
4. Different flanges require different gasket types. Flat plate flanges may use softer materials, while raised face or weld neck flanges might need higher-grade gaskets that can endure pressure and temperature variations.
5. Slip-on and flat plate flanges offer easier installation but may not provide the same level of pressure resistance as weld neck or blind flanges. Determine the trade-off between ease of installation and long-term durability based on system needs.

Find the Perfect Plate Flange for Your Waterworks System

Looking for reliable, high-quality plate flanges? 

Explore our plate flat welded steel pipe flanges, designed with durability, strength, and top manufacturing standards to enhance your waterworks and valve systems. 

Contact us to discuss your project requirements and find the ideal flange to boost your system’s performance!

FAQ Section 

Can plate flanges be used for all types of piping systems?
Yes, plate flanges are versatile and can be used in various piping systems, but the flange type and material must be chosen according to the system’s pressure, temperature, and fluid requirements.

How do I determine the pressure rating for my flange?
The pressure rating depends on factors like the flange material, pipe size, and application environment. It’s best to consult a flange pressure class chart or speak with a specialist for accurate selection.

Are plate flanges corrosion-resistant?
The corrosion resistance of a plate flange depends on its material. Stainless steel and certain alloys provide high resistance to corrosion, making them suitable for waterworks and corrosive environments.

What is the main difference between a raised face flange and a flat plate flange?
A: A raised face flange has a raised surface around the bore for improved sealing with a gasket, while a flat plate flange has a flat surface, making it suitable for low-pressure applications.

Can blind flanges handle both pressure testing and isolation?
A: Yes, blind flanges are specifically designed to seal off a section of piping or a valve, making them perfect for both pressure testing and isolating parts of a system for maintenance.

Resources:

13 Different Types of Flanges and Their Applications 

A Guide to Flat Plate Strainers

The Difference Between a Raised Face and Flat Face Flange

Understanding and Choosing Waterworks Valve Flanges

Benefits of Flanges

Slip-On Flanges