Emerson 3000 manual World Class, Figure A-12.Snubber Diffusion/Dust Seal Assembly

Instruction Manual

Appendix A Rev. 3.6 July 1998

World Class 3000

Figure A-12. Snubber Diffusion/Dust

Seal Assembly

d.Snubber Diffusion/Dust Seal Assembly

The snubber diffusion/dust seal assembly, Figure A-12,is used in applications where an abrasive shield is to be used with a snubber type diffusion element. The dust seal consists of two rings of packing to pre- vent abrasive dust from collecting inside the abrasive shield.

e.Bypass Probe Options

For processes where the flue gas exceeds the maximum allowable temperature of 1300°F (704°C) a bypass sensor package can be employed. The bypass system uses

an 18 inch (457 mm) or 3 foot (0.92 m) probe mounted externally on the stack or duct. The process or exhaust gases are di- rected out to the probe through a passive sampling system using inconel tubes. Flue gas flow induces the movement of gases into, through, and out of the bypass unit. The bypass arrangement does not require the use of aspiration air and the gas which flows past the probe is returned to the stack or duct.

The bypass probe package is normally used for process temperatures of 1300°F (704°C) to 2000°F (1094°C). A higher temperature version of the bypass provides for operation at temperatures up to 2500°F (1372°C). In this version the pick up tubes are made of a special high-temperature alloy.

Overall dimensions and mounting details of the American and European bypass sys- tems are shown in Figure A-13.

f.Probe Mounting Jacket Options

A probe mounting jacket option is available to allow the probe to operate at tempera- tures of up to 2000°F (1095°C). A separate instruction bulletin is available for this option.

A-8 Appendices Rosemount Analytical Inc. A Division of Emerson Process Management