AS-CSB2S to replace Johncrane Mechanical seal type  Type SB2S

 

AS-CSB2S heavy-duty dual cartridge mechanical seal is to replace Johncrane Mechanical seal type  Type SB2S.

Parameters:

TEMPERATURE LIMITS

350°F/180°C

PRESSURE LIMITS

Process pressure: 290 psi(g)/20 bar(g)

Barrier fluid: 215 psi(g)/15 bar(g)

SPEED LIMITS

65fps/20m/s

Material Combinations:

Seal faces: SiC/Carbon or SiC/SiC

O-rings: PTFE, EPDM, Viton, FFKM

Metals: AISI 329 and 316 standard, titanium, Hastelloy, UHB, 904, SAF 2507 for sea water applications

Springs: Nimonic steel

Bellow are Several variant of the design available for different services:

• Type CSB2A — designed for ANSI standard dimensions
• Type CSB2A-PR — designed for ANSI standard dimensions, including integrated pumping device
• Type CSB2B — designed for big bore dimensions
• Type CSB2B-PR — designed for big bore back plate dimensions
• Type CSB2S — designed for special dimensions, including metric sizes
• Type CSB2S-PR — designed for special dimensions, including integrated pumping device

Background Knowledge：
Why silicon carbide can be used for mechanical seals under high temperature conditions
High temperature can easily cause changes in properties of friction pair materials, deform the sealing faces or reduce their hardness, and reduce the service life of the mechanical seal. Therefore, how to solve the problem of thermal deformation, strength and wear resistance  conditions under high temperature are the key to selecting sealing materials for the friction pair of the mechanical seal. 

Silicon carbide has high strength under high temperature, and its flexural strength at 1400°C is the same as that at room temperature, so silicon carbide can be used for mechanical seals under high temperature conditions.