Pulverized Coal Flow Measurement Testing Requiremetns

[MechEng1995]

I am an engineer at a fossil fired boiler power plant. We are redesigning the coal nozzles for lower NOx. The units in question are equipped with CE Raymond Bowl Mills (RB-533) and B&W MPS-67 Pulverizers. We have hired a testing outfit to perform an isokinetic coal flow test on the coal piping risers after the mills. I am not that familiar with the testing code that governs this and I don't have a vast PTC ot ASME library. My questions:

1. What are the upstream and downstream straight pipe requirements for the test ports?

2. Does a victaulic coupling qualify as a disturbance?

3. Is a gate valve wide open a significant disturbance?

Thanks.

 

[davefitz]

refer to the following power test codes:
ASME PTC 4.2- pulverizers
PTC 38- fines measurement in gas streams

 

[rmw]

What type of gate valve? A regular gate valve or a knife gate?

rmw

 

[insult2injury]

We usually use 20D or longer if it can be accomodated for the straight pipe requirements but I think the PTC might be less stringent. We definitely wouldn't have any valves through that portion of pipe.

I2I

 

[MechEng1995]

A knife gate valve. No valves are upstream of the test ports, however, some are immediately downstream. (i.e. 2 to 3 D) The only thing other than elbows are victaulic couplings. Some pipes have a vic. coupling 2 to 3 D upstream from the ports. We have anywhere from 7 to 10 diameters upstream from any elbow.

Thanks.