CS Slip On Flange – Complete Guide by Fortis Forge
Introduction
In the industrial piping world, certain flange types stand out for their simplicity, reliability, and affordability. One such type is the CS (Carbon Steel) Slip On Flange. Designed to slide over the pipe before welding, this flange offers a secure and economical method for connecting pipelines in a wide range of industries.
At Fortis Forge, we manufacture CS slip on flanges that meet ASTM, ASME, ANSI, DIN, JIS, and EN standards, ensuring they perform flawlessly in high-pressure and high-temperature environments. Trusted by clients across oil & gas, chemical processing, water treatment, and power generation, our flanges deliver the perfect balance between performance and cost-effectiveness.
1. What Is a CS Slip On Flange?
A slip on flange is designed to slip over the outside diameter of a pipe and then be welded both inside and outside to provide strength and prevent leaks. It is preferred in low- to moderate-pressure applications where alignment ease is important.
Key Features:
Fits over the pipe without threading.
Requires less accuracy in cutting pipe length.
Allows easy alignment before welding.
2. Advantages of CS Slip On Flanges
Cost-Effective – Less expensive than weld neck flanges.
Easy Installation – Simple alignment before welding.
Flexibility – Suitable for a variety of pressure ratings.
Durability – Carbon steel ensures long service life.
Wide Availability – Produced in various sizes and classes.
3. Why Choose Carbon Steel for Slip On Flanges?
High Strength – Handles moderate to high pressure with ease.
Thermal Resistance – Performs reliably in temperature extremes.
Corrosion Resistance – Can be coated or galvanized for harsh environments.
Cost Advantage – More affordable than stainless steel while delivering comparable mechanical performance in many cases.
4. Types of CS Slip On Flanges
At Fortis Forge, we supply:
Raised Face (RF) Slip On Flanges – Common for most applications, providing a better gasket seal.
Flat Face (FF) Slip On Flanges – For use with cast iron or fiberglass flanges to prevent stress cracking.
Ring Type Joint (RTJ) Slip On Flanges – For high-pressure, leak-proof sealing in demanding environments.
5. Standards & Specifications
Our slip on flanges comply with:
ASTM A105 / ASTM A350 LF2 / ASTM A694
ASME B16.5 / B16.47
DIN, EN, JIS
Pressure Classes: 150, 300, 600, 900, 1500, 2500 lbs
Sizes: ½” to 60”
6. Manufacturing Process
Material Selection – High-quality carbon steel billets.
Forging – Improves structural integrity.
Heat Treatment – Normalizing, quenching, or tempering for strength.
Precision Machining – Ensuring accurate bore and bolt hole alignment.
Surface Finishing – Anti-rust coating, galvanizing, or painting.
Inspection & Testing – Verifying mechanical and dimensional accuracy.
7. Applications of CS Slip On Flanges
Oil & Gas Pipelines – Easy to install and align in field conditions.
Chemical Plants – Suitable for process piping where frequent maintenance is required.
Water Treatment Facilities – Ideal for pump and piping connections.
Power Generation – Cooling water, steam, and condensate systems.
Marine & Offshore – With coatings, withstands saline conditions.
8. How CS Slip On Flanges Are Installed
Slide the flange over the pipe end.
Position it at the desired location.
Weld the inside circumference (fillet weld).
Weld the outside circumference.
Attach the mating flange with bolts and a gasket.
9. Benefits in Maintenance & Operations
Quick Assembly & Disassembly – Ideal for systems needing frequent inspection.
Alignment Ease – Less precision cutting required.
Reusability – Can be removed and reused if undamaged.
Versatile Connection – Compatible with a wide variety of piping systems.
10. Quality Control at Fortis Forge
Each flange undergoes:
Hydrostatic Testing – To confirm leak-proof performance.
Ultrasonic & Radiographic Testing – Detecting internal defects.
Mechanical Testing – Tensile, yield, and hardness tests.
Dimensional Inspection – Ensuring proper fit and bolt hole alignment.
MTC Certification – EN 10204 3.1 / 3.2 compliance.
11. Why Fortis Forge Is the Preferred Supplier
International Standards Compliance – Meets or exceeds global specifications.
Custom Manufacturing – Special sizes, coatings, and drilling patterns available.
Large Ready Stock – Fast delivery to meet urgent project needs.
Competitive Pricing – Affordable without compromising quality.
12. Maintenance Tips
Always inspect the weld joints for cracks or wear.
Use proper gasket material for operating conditions.
Re-torque bolts after the system reaches operating temperature.
Store flanges in a dry, clean area to prevent corrosion.
13. FAQs
Q: Are slip on flanges suitable for high-pressure systems?
A: They are best for moderate pressure ratings, but high-class slip on flanges can handle elevated pressures with proper welding.
Q: How do slip on flanges compare to weld neck flanges?
A: Slip on flanges are easier to install and more affordable, while weld neck flanges offer better stress distribution for very high-pressure systems.
Q: Can CS slip on flanges be galvanized?
A: Yes, hot-dip galvanizing improves corrosion resistance for outdoor or marine use.
Conclusion
CS slip on flanges combine ease of installation, durability, and cost-effectiveness, making them an excellent choice for a wide range of industrial applications. At Fortis Forge, we ensure every flange meets strict quality standards, performs reliably under demanding conditions, and offers long service life. Whether you require standard sizes or tailor-made solutions, we deliver precision-engineered slip on flanges on time and within budget.