Suction plate, pump

The sani-open impellers have only one wearing ring. For liquids having comparatively high viscosity like molten sulfur a semi-open type impeller is usually preferred. These impellers are non-clogging and easy to clean whenever the pump is removed for maintenance. The frontal clearance, i.e., the distance between the suction plate/cover face and the impeller is very important when using a semi-open impeller. An increase in the frontal clearance drastically reduces the head or flow of the pump. 

The front suction plate, or throat bush in large pumps... 

The technique of the filtration of hot solutions has already been described in Section 11,28. The filtration of cold solutions will now be considered this operation is usually carried out when it is desired to separate a crystalline solid from the mother liquor in which it is suspended. When substantial quantities of a solid are to be handled, a Buchner funnel of convenient size is employed. The ordinary Buchner fimnel (Fig. 11,1, 7, a) consists of a cylindrical porcelain funnel carrying a fixed, flat, perforated porcelain plate. It is fitted by means of a rubber stopper or a good cork into the neck of a thick-walled filtering flask (also termed filter flask, Buchner flask or suction flask) (Fig. 11,1, 7, c), which is connected by means of thick-walled rubber tubing (rubber pressure tubing) to a similar flask or safety bottle, and the latter is attached by rubber pressure tubing to a filter pump the safety bottle or trap is essential since a sudden fall in water pressure may result in the water sucking back. The use of suction renders rapid filtration possihle... 

Sodium anthraquinone-p-sulphonate ( silver salt ). Place 60 g. of fuming sulphuric acid (40-50 per cent. SO3) in a 250 or 500 ml. round-bottomed flask and add 50 g. of dry, finely-powdered anthra-quinone (Section IV,145). Fit an air condenser to the flask and heat the mixture slowly in an oil bath, with occasional shaking, so that at the end of 1 hour the temperature has reached 160°. Allow to cool and pour the warm mixture carefully into a 2 litre beaker containing 500 g. of crushed ice. Boil for about 15 minutes and filter off the unchanged anthraquinone at the pump. Neutralise the hot filtrate with sodium hydroxide and allow to cool, when the greater part of the sodium anthra-quinone-p-sulphonate separates as silvery glistening plates ( silver salt ). Filter these with suction and dry upon filter paper or upon a porous plate. A second crop of crystals may be isolated by concentration of the trate to half the original volume. The yield is 40-45 g. 

Milk-of-lime transfer pumps should be of the open impeller centrifugal type. Pumps having an iron body and impeller with bronze trim are suitable for this purpose. Rubber-lined pumps with rubber-covered impellers are also frequently used. Makeup tanks are usually provided ahead of centrifugal pumps to ensure a flooded suction at all times. Plating out of lime is minimized by the use of soft water in the makeup tank and slurry recirculation. Turbine pumps and eductors should be avoided in transferring milk of lime because of scaling problems. 

Positive pumps are normally fitted with relief valves. These are not usually fitted to centrifugal pumps unless the process material is likely to explode if it gets too hot. As an alternative to a relief valve, such pumps may be fitted with a high-temperature trip. This isolates the power supply. Or a kick-back, a small-diameter line (or a line with a restrietion orifice plate) leading from the delivery line baek to the suction vessel, may be used. The line or orifice plate is sized so that it will pass just enough liquid to prevent the pump from overheating. Small-diameter tines are better than restriction orifice plates as they are less easily removed. 

Filtrier-erde, /. filtering earth. -flMche, /. filtering surface or area, -flasche, /. filtering flask, -gestell, n. filter stand, -hut, m. (paper) filtering funnel, -kessel, m. filtering boiler, -konus, m. filter cone, -korb, m. filtering basket, -nutsche, /. suction filter, -papier, n. filter paper, -papierstreifen, m. strip of filter paper, -platte, /. filter plate, -presse, /. filter press, -pumpe, /. filter... 

Figure 8.45. Single-stage, single-action liquid ring gas pump 1, shaft 2, impeller 3, casing 4, guide plate 5, suction port 6. discharge port 7, liquid ring...

Benzenesulphohydroxamic Acid.1—Hydroxylamine hydrochloride (10 g.) is boiled under reflux condenser with just enough methyl alcohol to dissolve it, and when still hot is decomposed by a solution of 3 g. of sodium in 60 c.c. of ethyl alcohol, which should not be added too quickly. After the mixture has been cooled, precipitated sodium chloride is removed at the pump and 8-5 g. of benzenesulphonyl chloride are then added in small portions to the solution of free hydroxylamine. Most of the alcohol is now removed by distillation from the water bath, the hydroxylamine hydrochloride which has separated is removed by filtration, and the filtrate is evaporated to dryness in vacuo at a moderate temperature. The residue is extracted three times with 15 c.c. portions of boiling absolute ether. Evaporation of the combined ethereal extracts in an open dish yields the benzene sulphohydroxamic acid in the form of a mass of crystalline plates which are digested with cold chloroform and filtered with suction. Yield 5-6 g. Melting point 126°. 

The residue in the flask is then filtered at the pump while hot, and the filtrate is strongly acidified with concentrated hydrochloric acid. When the acid filtrate is cooled the by-product of the reaction, benzoic acid, separates in glistening plates. These are filtered with suction, and recrystallised from boiling water. Melting point 121°. Benzoic acid is somewhat volatile with steam. 

For open system sump pump service, the pressure containing components Types VS4 and VS5 pumps are the volute casing, suction cover, and discharge fine. For closed system pressurized or vacuum tank service, the outer stuffing box or seal housing, pump cover plate, and tank cover also become pressure containing components. 

The components which constitute the pressure casing of Type V S7 pumps are the outer casing (complete with the discharge nozzle), the head plate, and the suction pipe. 

The horizontal pumps are available for capacities up to 900 m /h (4000 gahmin) the vertical in-line pumps, for capacities up to 320 m /h (1400 gahmin). Both horizontal and vertical in-line pumps are available for heads up to 120 m (400 ft). The intent of each ANSI specification is that pumps from all vendors for a given nominal capacity and total dynamic head at a given rotative speed shall be dimensionally interchangeable with respect to mounting, size, and location of suction and discharge nozzles, input shaft, base plate, and foundation bolts. 

Fig. 4.1-35. Diaphragm compressor (HOFER). a, Diaphragm b, Gas space c, Discharge valve d, Suction valve e, Diaphragm cover f, Perforated plate g, Hydraulic cylinder h, Oil overflow valve i, Oil return j, Cylinder cooling k, Check valve 1, Crank drive m, Cooling-water in/out n, Oil-cooling coil o, Oil chamber p, Oil injection (leakage compensation) q, Compensation pump r, Check valve s, Oil supply.

For suction pump systems where the potential for syphoning exists should the fuel feed line be broken when the dispenser is in operation, some jurisdictions require a valve that allows fuel flow from the tank only when the dispenser is in operation. These valves are typically made from brass and have an elastomeric diaphragm used to open the valve. The diaphragm within the valve must be methanol-compatible or it will rupture, causing the pump to draw air and lose prime. The valves should be nickel-plated and the diaphragm replaced with one made from teflon [4.4],... 

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