Document qm23rQ2Kjk5Oy9Ddk8RoDO1rG

| Hew Pullman-Standard operate* boiler* on a ll% blow-down basis.., with SORBO-CEL At tht Htskvll ft Bstktr plant of Pullm* a.jrsndirdCtrMfg.Co,,SorboCel *ol*d the major filintlon problem of i<nwi<i| oil from condtnnit rtru/ned to <h two new 90,000 Ib-pcrhr 400 pii, 750-F boiler*. ' Pre-Coat Sorbo-Cel and regalar Sorbo-Cel, specially proceurd high Row-rat*<fittomccotft tilice powder* era uaed on leaf-tfpe filter*. After a film of Pre-Coat Sorbo-Cel hsa been built op on tbe biter screen*, regular Sorbo-Cel la added continuously >o | the un6liered water. Tbii meau a new filter surface it comtently prerented to lb* oncoming water. I Remit*... Water filtered bp SorboCel contained lei* than 0.1 ppm of oil , ... and boiler*.have <inc been oper ated onaeoe perreal blow-down bttlt. Send coupon below for bulletin giv ing data on thii low-con wap tnst to remove oil from water. No IJiM con or obligation. IlfMl Johns-Manville SORBO-CEL Johns-Maavflfe s-ow-t^ Boa 60, Naw York Id, N. Y. i Pltait tend me free bulletin giving [ advinugea of Sorbo-Cel filtration. Mmn_ --- 228 More TECHNICAL BRIEFS P*gMf * gfp* /J4 Obaened transient in phase and cathode currents were not dangerously high, but piovcd mote severe titan when auxiliary power was maintained while load was dropped, leading lo the conclusion that provision should be mode in proposed higher-capscity installations to maintain auxiliary power. However, the teats showed there is no cause (or concern in cases o( power failure in which the' auxiliary power supply would be lost. 3. Load interruptions by short-cir. cutting the firing circuit should nol be considered in large reetifier installations because of excessive overcurrem and accompanying arc-back. 4. Load interruption by operation of cathode circuit breakers is not recom mended because the last breaker has to clear as much as one half the normal polling current. 5. At Mead, it la satisfactory to pick up load by removing the short circuit on the firing circuits, followed by clos ing the ac circuit breaker. In general, it is recommended that loads be picked up by removing the short circuit on the igniter circuit after the ac circuit breaker is closed- Such procedure re duces the maximum transient eurrent on the ac system since load current duet not Sow timnltaneouily with trans former inrush current. 6. The order, of magnitude of indue-, lance on aluminum potlines is less than one millihenry. This figure, originally arrived at by calculation, was confirmed by these tests. 7. It ii improbable tliot failures of rectifier transformers on earlier instal lation* were ,caused by voltage surges resulting from circuit-breaker opera tions. A!EE Paper No. 53-65. Capacitors In Power Systems with Roctlflov leads. By A Schmidt, Jr, General Electric Co. Static capacitors have come into wide use as an efficient and economical aource of reactive power for ac systems- Har monic voltages are sometimes a problem when applying capacitor! to a system. In early days the principal sources of system harmonics were rotating mechinea end transformers. More recently, the widespread application of mercuryarc rectifiers has Introduced other sources of system harmonics. These often require consideration when rec tifiers end capacitors ore connected to the same system. Parallel-type resonance between ca pacitors and system reactance in the presence of harmonic sources, such as power rectifiers, may cause: (11 Over* Pfitcfto"! fw tfOttlnf yepwt m * IM With steel-to-stael, brotue-to-itetl, stain less nhI-imiecI or orifice tea u. 3000-lb. sendee only,' fnm STAINLESS & run AUOV SHU UNIONS Wiih screwed or | Isocket weld ends. 3000-lb. snd 8000-lb. service. WRITS FOR CATALOG >< sbowlitq the complete CotowfiM Perfect Seof product* CATAWISSA VALVS FITTINGS COMPANY 20* MILL ST. . CATAWISSA t*j Last Longer, Save You Money ore and more boilers gnd industrial furnaces are being lined with A.P. Green engineered monolithic refractory linings, because furnace operators recognise the savings available In terms of longer life end lower maintenance costs. Monolithic construction, utilising A. P. Green castable and plastic refractories, results in a lining which reduces "down time," cuts maintenance costs, and lasts longer. It Is o combination of the highest qualify mofen'ol* and sound refractory engineering. For properly engineered one-piece monolithic furnoce linings which ere airtight, with no exposed Joints open to attack by flame or slag. .. linings that are quickly ond easily installed ... do not bulge ... and give longer life--call your local A. P. Green distributor. He Is listed in the yellow pages of your telephone directory. Distributers to (hr P'indcaf Cities tube World A.P.ORI1N FIRE BRICK CO. M*be. WiimA U. i. A. a. f. okcn m Mteir coMMArr. tro.