Sump temperatures

Polyol ester turbine oils currendy achieve greater than 10,000 hours of no-drain service in commercial jet aircraft with sump temperatures ranging to over 185°C. Polyol esters are made by reacting a polyhydric alcohol such as neopentyl glycol, trimethylol propane, or pentaerythritol with a monobasic acid. The prominent esters for automotive appfications are diesters of adipic and a2elaic acids, and polyol esters of trimethylolpropane and pentaerythritol (34). 

The flow scheme of the process(17) is represented in Fig. 2. The required throughput rate of 5 kg Pu/day is obtained in a batch-type operation, where a 5 to 10% substoichometric oxalate precipitation is performed by adding solid oxalic acid to a 3 M HNO - 100 g/L Pu(NO3) 4 solution at 80°C in about 2 hours. Up to 95% of the Pu is precipitated as uniform crystals of 20 yum average size and filtered. After washing and calcination, the average analysis of this product shows less than 1000 ppm total metallic impurities. When evaporating the filtrate to about 5% of its original volume, nitric acid is recovered, and most of the oxalic acid is destroyed. This results from sump temperatures of up to 123°C and the presence of Pu(VI). 

Whatever the specification system, successful engine lubricants must satisfy a wide range of functions. They must ensure the operating reliability of the many friction points in engines. Table 17.1, but additionally must seal and cool the piston/cylinder interface and also transport metallic debris, soot and degradation products to the filter. Hydrodynamic and elastohydrodynamic conditions exist in bearings, whilst boundary conditions exist at the top and bottom dead centres (TDC and BDC) of sliding piston simple harmonic motion. Temperatures can vary from -50°C at start-up to 100°C-i- sump temperatures and >300°C peak values under the piston crown. The issues to be addressed for each lubricant formulation are included in Table 17.1. 

This time limit is established in the Topical Report CENPD-201-A. Combustion Engineering will perform a test to verify the analysis in Appendix A. The component cooling water will be secured to the pump lubrication oil sumps and data taken so as to demonstrate the heat up rate of the oil sump up to a maximum sump temperature of 200 F. A test securing cooling water to the pump seals will also be performed to demonstrate the seals operability as detailed in Combustion Engineering Topical Report CENPD-201-A. In the remote possibility of a simultaneous loss of component cooling water to all reactor coolant pump motor assemblies, 30 minutes is adequate to secure the plant and maintain the normal coast down capabilities of the reactor coolant pump motor assemblies. 

Also of Interest Is that what Is Che limitation of oil sump temperature. In particular, cold start-up conditions,... 

Ring oiling for small machines is used predominantly when the additional cost of a pumping system cannot be justified. ITie system enjoys the advantage of selfcontainment, needing no external motivation for its performance. Cooling coils are sometimes added when the sump temperature may become excessive. 

N2, and traces of PH, CO2, E, and S large furnaces generate off-gas at a rate of about 120—180 m /min. In most installations the off-gas is passed through a series of Cottrell electrostatic precipitators which remove 80—95% of the dust particles. The precipitators ate operated at temperatures above the 180°C dew point of the phosphoms. The collected dust is either handled as a water slurry or treated dry. Einal disposal is to a landfill or the dust is partially recycled back to the process. The phosphoms is typically condensed in closed spray towers that maintain spray water temperatures between 20 and 60°C. The condensed product along with the accompanying spray water is processed in sumps where the water is separated and recycled to the spray condenser, and the phosphoms and impurities ate settled for subsequent purification. 

Pressure Zero shift, air leaks in signal lines. Variable energy consumption under temperature control. Unpredictable transmitter output. Permanent zero shift. Excessive vibration from positive displacement equipment. Change in atmospheric pressure. Wet instrument air. Overpressure. Use independent transmitter mtg., flexible process connection lines. Use liquid filled gauge. Use absolute pressure transmitter. Mount local dryer. Use regulator with sump, slope air line away from transmitter. Install pressure snubber for spikes. 

A dry sump design should be employed. The gear unit for a train with a central lube oil system should be designed for the turbine grade oils of the system. Typically, 150 Saybolt Seconds Universal (SSU) oils at 100°F (ISO 32) with an inlet temperature of 110°F to 120°F are adequate. 

A similar incident occurred on another plant. The liquid in the plant was cold, so a low-temperature alarm was installed in the sump. It was tested with cold water and worked well. When a leak occurred, the leaking liquid, which was acidic, reacted with the steelwork on its way to the sump and warmed up the temperature element could not, of course, tell the difference between warm air and warm liquid and failed to detect the leak. 

Blowdown and drains may be taken to either a sump or blowdown tank prior to discharging into the drains. The purpose of this is to reduce the temperature by dilution and dissipate the pressure to prevent damage to the drains. 

The pour point of the lubricant should be at least 10°C lower than the expected minimum ambient starting temperature. If the ambient starting temperature approaches the pour point, sump heaters may be required to ease starting and ensure adequate lubrication. Viscosity ranges are provided to allow for variations such as surface finish, temperature rise, loading and speed. 

If long distillation time is a problem, one can move to continuous distillation with conventional shell and tube heaters accompanied by a typical column bottom (often called a sump) which is a high temperature holdup, or better yet a short path evaporator (falling film, thin film, or wiped film) with usually a smaller receiver (called an accumulator in this case). The most chemical damage is in the thin liquid film at the heat transfer surface, so the short path evaporators do the least thermal damage. 

Of course the only way to keep this 250W behemoth running for more than a minute without hitting the IC s internal OTP (over temperature protection) was to use a water-cooled heatsink, which my rather lab-ratty senior tech fashioned in less than half a day with some tubes, strips of metal, high-temp solder, and a sump (submersible pump). Note that the dissipation in the TO-220 was about 15W at this power level (calculated and measured). Yes, if you think that is a wee bit too much for a TO-220 to handle, I am on your side. 

Worms work best at temperatures between 50 and 77°F (12-25°C). They will survive considerably lower temperatures, but their rate of producing compost will slow down. Keep a worm bin where temperatures do not fluctuate widely—out of direct sunlight in summer. Bring the bin into a garage or warm greenhouse in winter, or insulate it well before the cold weather starts. A worm bin with an integral drainage sump can be kept indoors, in a shed or porch, for example, and moved out in the summer. Other bins may need to be set on bare soil to absorb any excess liquid produced. 

The boiling point of water, at 10 psig, is about 240°F. This means that the temperature in the entire water draw-off sump is 240°F. But the pressure at point B is 1 psi above the water s bubble, or boiling point. We say, then, that the water at point B is subcooled by an equivalent of 28 in of liquid, or 1 psi. 

Range—The numerical difference between the temperature of the hot water entering the cooling tower at the distribution system and the temperature of the colder water leaving the sump basin. 

Tapproach = CWT °F/C° WBT °F/C° where CWT = tower sump cold water temperature and WBT = ambient air wet bulb temperature... 

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