ANSI B16.5 ASTM A182 UNS S31008 Slip On RTJ Flange DN40 Class600

Type: Slip On RTJ Flange
Material: Grade 310S (UNS S31008)
Size: 1-1/2″ (DN50)
Class: 600#
Norm: ANSI B16.5

Stainless steel 310/310S is an austenitic heat resistant alloy with excellent resistance to oxidation under mildly cyclic conditions through 2000°F. Its high chromium and nickel contents provide comparable corrosion resistance, superior resistance to oxidation and the retention of a larger fraction of room temperature strength than the common austenitic alloys like Type 304. Stainless 310 is often used at cryogenic temperatures, with excellent toughness to -450°F, and low magnetic permeability.

A Ring Type Joint Flange, abbreviated as RTJF, is a type of flange that uses a metal ring that sits in a hexagonal groove as a gasket to seal the flange pair. The flanges seal when the bolts are tightened and the gasket is compressed into the groove making a metal to metal seal. An RTJ flange usually has a raised face with the groove machined into the face of the flange. The raised face doesn’t serve as a way to contain the pressure. 

RTJ Flanges are used for high pressure applications up to pressures as high as 15,000 psi (103 MPa). It is only furnished only on steel or alloy valve bodies and usually need to specified when ordering. The flanges usually come in blind, slip-on, threaded and weld neck. The benefits of using an RTJ flange and ring is that the gasket is confined to a groove and has two sealing surfaces. The groove assures that the ring centers itself when the bolts are tightened. It also is self actuating meaning that the sealing pressure increases when the process pressure increases. The disadvantages of using RTJ Flanges is that ring type joint grooves can accumulate dirt or moisture when the flange is open. Since the seal is a metal on metal connection, a small amount of damage on the narrow sealing surface(s) may lead to a leak. Additionally, the grooves and gasket must align properly in order to assemble the flange and obtain a seal. They must stay aligned throughout the operating cycle. This is important if you are flanging up to dissimilar metals like stainless steel to carbon steel flanges.

Chemical composition % of Grade 310S (UNS S31008)

%	Cr	Ni	C	Si	Mn	P	S	Mo	Cu	Fe
310	min: 24.0 max:26.0	min: 19.0 max: 22.0	0.25	0.75	2.0	0.045	0.030	0.75	0.5	balance
310S	min: 24.0 max: 26.0	min: 19.0 max: 22.0	0.08	1.00	2.0	0.045	0.030	0.75	0.5	balance

Mechanische eigenschappen of Grade 310S (UNS S31008):

Rang	Treksterkte ksi (min.)	Yield Strength 0.2% Offset ksi (min.)	Elongation – % in 50 mm (min.)	Hardheid (Brinell) MAX	Hardheid (Rockwell B) MAX
310/310S	75	30	40	217	95

Fysieke eigenschappen of Grade 310S (UNS S31008):

Denstiy lbm/in3	Coefficient of Thermal Expansion (min/in)-°F			Electrical Resistivity mW-in		Thermal Conductivity BTU/hr-ft-°F		Specific Heat BTU/lbm -°F	Magnetic Permability (annealed)1	Modules of Elasticity (annealed)2-psi
at 68 °F	at 68 – 212°F	at 68 – 932°F	at 68 – 1832°F	at 68°F	at 1200°F	at 68 – 1832°F	at 68 – 932°F	at 32 – 212°F	at 200H	in tension (E)	in shear (G)
0.29	8.8	9.5	10.5	30.7	-	10.5	10.8	0.12	1.02	29 x 106	11.2 x 106

What are the characteristics of 310/310S Stainless?

• Oxidation resistance to 2000°F
• Moderate strength at high temperature
• Resistance to hot corrosion
• Strength and toughness at cryogenic temperatures

Typical Applications for 310/310S Stainless

• Kilns
• Heat Exchangers
• Radiant Tubes
• Muffles, retorts, annealing covers
• Tube hangers for petroleum refiing adn steam boilers
• Coal gasifier internal components
• Saggers
• Furnace parts, conveyor belts, rollers, oven linings, fans
• Food processing equipment
• Cryogenic structures

Fabrication with Stainless 310/310S

Type 310/310S is readily fabricated by standard commercial procedures. In comparison to carbon steel, stainless steels are tougher and tend to work harden rapidly.

Type 310/310S can be welded using all of the common welding processes.