ASTM A795

Description

ASTM A795 Pipe

ASTM A795 is a specification published by ASTM International that covers black and hot-dipped zinc-coated (galvanized), welded and seamless steel pipe intended for use in fire protection systems.

Key Features of ASTM A795

• Application: Primarily used for fire protection piping systems, such as sprinkler systems, standpipes, and fire water mains.
• Types:

1. Type E – Electric-Resistance Welded (ERW)
2. Type S – Seamless

• Grades:

1. Grade A – Standard grade for most applications.
2. Grade B – Higher strength variant, less commonly used in fire protection.

• Coating Options:

1. Black (uncoated)
2. Hot-Dip Galvanized – Zinc-coated for enhanced corrosion resistance, particularly important for outdoor or humid environments.

• Sizes: Covers NPS (Nominal Pipe Sizes) from 1/2″ to 10″, with corresponding wall thickness suitable for fire protection use.
• Pressure Ratings: Vary based on wall thickness and pipe size, typically suitable for standard fire system pressures.
• Ends:

1. Plain End (PE)
2. Threaded End (TE)
3. Grooved End (common in fire protection for mechanical joining)

Size & Dimensions

ASTM A795 Schedule 10 (S10) Sizes

• 1/2″ NPS (1.315″ OD) x 0.109″ wall 
• 1″ NPS (1.315″ OD) x 0.109″ wall 
• 1 1/4″ NPS (1.660″ OD) x 0.109″ wall 
• 1 1/2″ NPS (1.900″ OD) x 0.109″ wall 
• 2″ NPS (2.375″ OD) x 0.109″ wall 
• 2 1/2″ NPS (2.875″ OD) x 0.120″ wall 
• 3″ NPS (3.500″ OD) x 0.120″ wall 
• 3 1/2″ NPS (4.000″ OD) x 0.120″ wall 
• 4″ NPS (4.500″ OD) x 0.120″ wall 
• 5″ NPS (5.563″ OD) x 0.134″ wall 
• 6″ NPS (6.625″ OD) x 0.134″ wall 

ASTM A795 Schedule 40 (S40) Sizes

• 5″ NPS (5.563″ OD) x 0.280″ wall (example of thicker wall for Schedule 40) 
• 6″ NPS (6.625″ OD) x 0.280″ wall (example of thicker wall for Schedule 40) 
• 8″ NPS (8.625″ OD) x 0.277″ wall (example of thicker wall for Schedule 40) 
• 10″ NPS (10.75″ OD) x 0.365″ wall (example of thicker wall for Schedule 40) 

Standards Referenced

• NFPA 13 – Standard for the Installation of Sprinkler Systems
• FM Approved & UL Listed pipes are often specified under ASTM A795 for compliance with fire safety authorities.

Equivalent or Related Standards

• ASTM A53 – General purpose pipe (also sometimes used in fire protection)
• ASTM A135 – Similar to A795 but with slightly different manufacturing and testing criteria

Applications

• Automatic sprinkler systems
• Fire hose standpipes
• Fire water mains
• Wet, dry, deluge, or preaction fire protection systems