I have a question about heat tracing for an application where there are outdoor, continuously sloped boiler drain lines (1.5" to 2", sch. 80 and 160, CS and P22) running to a blowdown tank. I can undertand the need to heat trace upstream of the last block valve in the line but what about heat...
I assume you are talking about advantages and disadvantages when compared to a traditional wedge gate valve.
The two main advantages of parallel slide gate for steam service are:
1. A parallel slide gate valve is much less likely to get stuck in the closed position. This is because the gate is...
Since the pump is already operating, you can determine the friction loss through your system by comparing the channel inlet water level with the level at the pump. Same with the friction loss across the screen.
rmw makes a good point about checking the minimum submergence of the pump. If you...
In my experience, the requirement to keep a stand-by pump warm depends on the design of the pump. Therefor, I'd stick to whatever the pump manufacturer's recommendations are. I've seen pumps that handle 375 deg F water that do not need any type of warm-up prior to start-up.
If you have a pump...
I think that spiral wound gaskets are overkill for the types of systems you're describing. I've always used the fibre-elastomer flat gaskets for 150# water systems like these. The cost of using spiral wound gaskets just doesn't make sense. Also, if you're in a jam, you can cut a flat gasket...
This may not be applicable to your case, however, I've generally specified cone or dome type roofs depending on the corrosiveness of the fluid contained in the tank.
For example, a demineralized water tank would have a dome type, self supporting roof with no internal bracing. Thus there is no...
I assume your are referring to rubber lined butterfly valves.
The manufacturer's I'm familiar with claim that the rubber lining will prevent seawater from ever contacting the shaft and therefor they typically provide 304SS or 420SS shafts.
The seals are usually nitrile.
I've heard of this problem occurring with a number of other F91 valves. I believe the problem lies in the procedure originally used to apply the Stellite 6 overlay on the F91 material. These failures prompted valve manufacturers to change the overlay procedure and perform additional NDE and I...
I heard an argument that it is necessary to use B7 studs instead of B8 studs for ANSI stainless steel flanges. This is due to the recommended torque creating a bolt stress that would exceed the yield stress of the B8 studs.
I've worked offshore previously and have always used B8 studs in...
In a compressed air system that has a compressor, dessicant dryer and air receiver, where is the best location for the dryer?
i.e. should it be upstream or downstream of the receiver.
I've always placed the dryer downstream of the receiver simply based on previous projects our company has...
In ASME Section I, PG-61.1 it states that the feedwater supply shall be capable of feeding the boiler at a pressure 3% higher than the highest relief valve setpoint on the boiler. It also lists a few exceptions where this requirement does not need to be met. Does anybody know specifically if...
