Valves float

Ghtsch, Inc. and (c) Nutter Float Valve, courtesy of Nutter Engineering Co. 

Float Valve Tray Design Manual, Nutter Engineering Co., Tulsa, OHa., 1976. 

A float valve is provided to control the supply of makeup water to replace the water vapor that has flashed off, Tne flash tank should be insulated. 

Fractionation Research, Inc. Report of Tests of Nutter Type B Float Valve Tray, July 2, 1964 from Nutter Engineering Co. 

Float Valve Figures 8-69A, 69B Nutter High Hlgh/High Medium Good... 

Figure 8-69B. Nutter float valves in open and closed positions for use on distillation trays. Used by permission, Nutter Engineering, Harsco Corp., Bui. N-2.

Trays FLOAT VALVE tray Rectangular valve M Mod Med Med Med Lateral release of... 

Screened Sump, Overflow. Float Valve Basin Drain, Wood Basin Only. 

Bleed-Off Line. This line bleeds off pressure within the standpipe, rotary base, kelly and the drill pipe to the depth of the top float valve. The bleed-off line allows air (or gas) under pressure to be fed directly to the blooey line. 

Make-up water. A semi-sealed section within the main tank will feed water from the treatment plant to the main tank either through a separate make-up tank or. In either case, the water level will be the same in both sections, excluding the ullage left for condense returns. Control of the make-up water level may be by float valve, float switches or conductivity probes. These methods allow water to flow through the treatment plant, although conductivity probes or switches permit a positive flow and avoid the risk of slippage. 

Flooded evaporators require a constant liquid level, so that the tubes remain wetted. A simple float valve suffices, but must be located with the float outside the evaporator shell, since the surface of the boiling liquid is agitated and the constant movement would cause excessive wear in the mechanism. The float is therefore contained within a separate chamber, coupled with balance lines to the shell (see Figure 8.1). 

Figure 8.1 Low-pressure float valve on flooded cooler...

On a single-evaporator flooded system, a float valve can be fitted which will pass any drained liquid from the condenser direct to the evaporator. The action is the same as that of a steam trap. The float chamber is at condenser pressure and the control is termed a high-pressure float (Figure 8.3). 

High-pressure float valves plus handset throttle valves for some flooded and low-pressure receiver circuits. 

Float thermostatic steam traps employ a float valve that rises in the presence of condensate and then opens to permit the discharge of the condensate. 

Water discharges from the bottom outlet of an open tank 1.5 in by 1 m in cross-section. The outlet is equivalent to an orifice 40 mm diameter with a coefficient of discharge of 0.6. The water level in the tank is regulated by a float valve on the feed supply which shuts off completely when the height of water above the bottom of she tank is I m and which gives a flowrate which is directly proportional to the distance of the water surface below this maximum level. When the depth of water in the lank is 0.5 m the inflow and outflow are directly balanced. 

Since boron trichloride reacts with many lubricants to form hydrogen chloride, the diboron tetrachloride synthesis is carried out in a grease-free system. A mercury float-valve vacuum system4 depicted in Fig. 15 is employed here. The U-traps have a capacity of 50 ml. without plugging and tubes A and B have... 

Automatic refilling using an automatic float valve should be provided. A maximum refill time of 8-hours is recommended (NFPA 22). Low-level alarms to protect the pumping unit should be provided. Suction pits associated with reservoirs should be monitored by level alarms to detect suction screen plugging. 

Another important item to maintain regularly is the float valve that supplies make-up water to tanks of heated cleaning solution. Float valves are used to maintain the level in the tank so that the heating coils/elements do not become exposed. While maintaining an adequate level is extremely important, it is also important that the valve does not leak and result in dilution of the cleaner. In addition to maintenance, use of frequent analytical checks is a good way to detect slow leaks. 

Float valve control for water and syrup feed... 

The choice of a filler depends on the number of bottle sizes being considered for use on it. For example, if 3 1 PET bottles are to be filled, a 126 mm pitch between filling valves is required. If only small bottles up to 500 ml are to be filled, then a 70 mm pitch will suffice. This has a direct effect on the size of the filler and its footprint on the factory floor. Unless the filler bowl level is kept within tightly controlled limits, pressure head variations will affect the rate of flow into containers. Systems such as that shown in Figure 7.15 need to be employed. Wherever possible there should be minimal contact between any instrumentation and the product. Conventional float valves should be avoided and simple capacitance probes, which are easily cleanable but small and very effective, should be used. It is not uncommon in older fillers to only have one float valve. This often gives rise to filler bowl flooding, which may lead to inconsistent fill level and poor counter-pressurisation of the container pre-filling. 

Makeup-This term refers to the water required to replace the circulating water that is lost by evaporation, drift, blowdown and leakage. It is expressed as a percentage of the water circulated and normally is automatically controlled by a float valve. 

Float valves are required on all cooling tower systems. Their purpose is to supply makeup water to replace that lost by evaporation, blowdown, drift and system leakage. They are usually installed in the cold water basin and function to maintain a preestablished water level. A typical flowsheet showing the recommended arrangements for instrumentation and valves is given in Figure 7.4. 

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