Simple Push-Pull Glass Valves Wc have developed several nmwnient push-pull glass valves for use in our work with circulating Ens strcmn* The w l w s can br used in place c d rotary glam:aup.wks fnr rontrulling the dirrctiun of fluid flow T h e y are 1l.w in rk ct rrlnti\r tcr meutl push-pull valvesand n m r y glass stopcocks ( p s r t m h r l y those of l a q r hmestzr, Addit:onal advantnaer 0 ~ 1 tncu h ~ valvti include: an absence of ground glass surfaces, little exposure t o grease, ease of fabrication by a glass blower, and provision for rapid switching without the necessity for careful visual alignment of tube openings
Each valw consists of a cvlindriral barrel with attached port*, and a grcmvrd sliding glas.; n d ot'mnall~rdmmrter. The rod i.; fitted w t h O-ring., tlightly grracedl in each groove. I)-rings provdea seal between the md and the twrel and dlrect fluid flow from nnd t o t he barrel ports. The nd is moved i rm e l t h e r oftwo poswmr in order torhnngr tlw d ~ r c v t ~ uufn the tl
