초록 ▼

An improved double block and double bleed stream switching system (modifiable to, for example, a double block, single bleed stream switching system) includes a common stream path for a multitude of gas streams from, for example, a process pipeline. The improved stream switching system includes a hea

An improved double block and double bleed stream switching system (modifiable to, for example, a double block, single bleed stream switching system) includes a common stream path for a multitude of gas streams from, for example, a process pipeline. The improved stream switching system includes a heating mechanism and insulation oven to help temperature stabilization, along with a structure to separate temperature sensitive solenoids from the heated area. Pre-heat coils are located between the sample switching system and the sample shut off system to warm the gas sample and to act as a flow restrictor. A first embodiment is suited for the Division 1 environment and a second embodiment is suited for Division 2 uses. The improved stream switching system may also feature membrane or cartridge filters located upstream of the sample wetted portion of the stream switching system.

대표청구항 ▼

What is claimed is: 1. A stream switching system, comprising: a stream switching housing having at least one common stream channel portion with a plurality of input ports and at least one output port; tubing connected at least one of said output ports, said tubing at least in part being a pre-heat

What is claimed is: 1. A stream switching system, comprising: a stream switching housing having at least one common stream channel portion with a plurality of input ports and at least one output port; tubing connected at least one of said output ports, said tubing at least in part being a pre-heat coil suitable to heat a fluid sample traveling through said coil and to act as a flow restrictor for flow restriction of said fluid sample, the extent of said flow restriction sufficient to restrict said sample flow to about 50-70 cc/mm. 2. The stream switching system of claim 1, further comprising: an insulated housing forming an interior region and encapsulating said stream switching housing in said interior region, said insulated housing stabilizing a temperature of said stream switching housing. 3. The stream switching system of claim 2, further comprising a heater within said interior region. 4. The stream switching system of claim 3, wherein said fluid flow actuation switches connect to said insulated housing. 5. The stream switching system of claim 3, wherein said fluid flow actuation switches are remote from said insulated housing. 6. The stream switching system of claim 2, further comprising: a plurality of gas flow actuation switches positioned outside of said insulated housing; piping connecting said plurality of fluid flow actuation switches to said insulated housing. 7. The stream switching system of claim 6, wherein said fluid flow actuation switches are solenoids. 8. The stream switching system of claim 7, wherein said piping connects said solenoid to said stream switching housing. 9. The stream switching system of claim 1, wherein there are more input ports than output ports. 10. The stream switching system of claim 1, further comprising at least one sample shut off switch connected to a downstream end of said tubing. 11. The stream switching system of claim 10, wherein said sample shut off switch includes a bleed port. 12. The stream switching system of claim 1, wherein each of input ports and output ports are individually actuatable. 13. A stream switching system, comprising: a housing forming an interior flow path for gas samples, said flow path connecting to the exterior of said housing via a first number of input ports and a second number of output ports, wherein said number of input ports is greater than said number of output ports; and piping connected to at least one of said output ports, said piping heating said gas samples to about a predetermined temperature. 14. The stream switching system of claim 13, wherein said housing further forms a sample shut off channel with an external bleed port, and further wherein said piping is upstream of said sample shut off channel. 15. A stream switching system, comprising: a stream switching housing having at least one common stream channel portion with a plurality of input ports and at least one output port; tubing connected at least one of said output ports; insulation surrounding said stream switching housing and said tubing; a heater to warm said stream switching housing and said tubing to a predetermined temperature; said tubing at least in part being a pre-heat coil suitable to heat a fluid sample having a liquid portion and to act as a flow restrictor for flow restriction of said fluid sample such that said fluid sample is heated to said predetermined temperature. 16. The stream switching system of claim 15, wherein said predetermined temperature is eighty degrees Fahrenheit. 17. The stream switching system of claim 15, further comprising: a gas chromatograph attached to said output port; wherein said gas chromatograph is maintained at a second predetermined temperature and said predetermined temperature for said fluid sample is the same as said second predetermined temperature.