US2596587A - Steam-lifting trap for steamcirculating systems - Google Patents

Description

y 1952 F. s. MORTON 2,596,587

STEAM LIFTING TRAP FOR STEAM CIRCULATING SYSTEMS Filed Dec. 22, 1948 4 Sheets-Sheet 1 May 13, 1952 F. s. MORTON 2,596,587

STEAM LIFTING TRAP FOR STEAM CIRCULATING SYSTEMS Filed Dec. 22, 1948 4 Sheets-Sheet 2 l l 1 l l l l l l l I I I l //2 van 12v: W A. mmlzw A lforheys.

y 1952 F. s. MORTON 2,596,587

STEAM LIFTING TRAP FOR STEAM CIRCULATING SYSTEMS Filed Dec. 22, 1948 4 Sheets-Sheet 4 Patented May 13, 1952 STEAM-LIFTING TRAP FOR STEAM- CIRCULATING SYSTEMS Frederick Stanley Morton, Enfield, England, as-

signor to Thermomatic (Engineers) Limited, Enfield, England, a British company Application December 22, 1948, Serial No. 66,657 In Great Britain January 1, 1948 Claims. (01. 137-103) This invention relates to steam-circulating systems for central heating and the like purposes.

In such systems it is usual to provide means for draining condensed water from the system and returning it to the boiler. This invention is concerned with the type of apparatus in which the condensate drains into a chamber containing a float which controls a valve device for admitting live steam to the sump when it is full so as to force the collected condensate back to the boiler, the valve device being thrown over to cut off the steam and connect the sump to atmosphere as soon as it is emptied, and remaining in this position until the sump is again full of condensate. In such an apparatus, the pipe by which the condensate drains into the sump and the pipe by which the condensate is returned from the sump to the boiler are provided with non-return valves which prevent the condensate from being forced back into the steam-circulating system when the sump is under steam pressure, and prevent water from being forced into the sump from the boiler when the sump is under atmospheric pressure.

In the improvement according to the present invention, the float controlled valve device comprises a pair of simple or compound valves, which control, respectively, a steam inlet and an atmospheric vent, and both of which valves are operated by a common sliding member disposed horizontally and provided with inclined faces which are engaged by corresponding inclined faces of a boss on a rod extending upwards from a float within a sump. The co-operation of these mutually engaging inclined faces causes the valve member to be displaced endwise as the float rises or falls, and the arrangement is such that when the float reaches the top of its travel, the steam inlet is opened and the atmospheric vent closed, and when the float descends to its lowest position, the steam inlet is closed and the atmospheric vent opened, the action being positive in both directions.

It is further desirable to ensure that the steam valve does not open until the chamber is full, and, when once opened, does not close again until the chamber is empty.

This is accomplished, according to a feature of this invention, by providing a spring-loaded device for retaining the float in its highest and lowest positions, the springs of which device are strong enough to retain the float in its highest position except when the chamber is substantially empty, and in its lowest position except when the chamber is substantially full, 1. e. the

2 springs will only yield and release the float when subjected to the full weight of the float and elements supported by it or when the float is fully submerged and its buoyancy is a maximum.

With this arrangement, the total travel of the float may be small relatively to the total rise and fall of the water level in the chamber.

In one preferred embodiment, the springloaded device takes the form of a ball catch comprising two or more spring-loaded balls engageable with one or other of two grooves in an upward extension of the float rod.

In another preferred embodiment, the springloaded device is of the toggle type and comprises horizontally movable spring-loaded plungers connected to an upward extension of the float rod by toggle links.

Since in either preferred embodiment, i. e; that comprisin the ball catch and that having a toggle device, the spring restraint on the float and parts supported thereby is the same in both the highest and lowest positions of these parts, it follows that the net upward force exerted on the spring-loaded device when the float chamher is substantially full must be equal to the downward force on the spring-loaded device when the float chamber is substantially empty. This can be achieved by appropriately weighting the float in relation to its buoyancy.

According to a feature of the invention, the valves respectively controlling the steam inlet and atmospheric vent are compound valves each comprising a needle-type valve and a pistontype valve operative in. series, the piston-type valves being so arranged that substantially the full stroke in the appropriate direction of the common sliding member is required to open one or the other of them completely.

The accompanying drawings illustrate, by way of example, several embodiments of the invention. In the drawings:

Figure 1 is a diagram of a steam-heating system embodying an apparatus for returning condensate to the boiler according to the present invention;

Figure 2 is an elevation of the apparatus partly sectioned;

Figure 3 is a central vertical section of the upper part of the apparatus;

Figure 4 is a section on the line 4-4 of Figure 3;

Figure 5 is an elevation, partly in central section, of a modified form of the uppermost part of the apparatus; and

pl ed Figure 6 is a part plan, part section, on the line 6-6 of Figure 5. 7

Referring to Figure 1, a boiler It delivers live steam to an uptake pipe H which feeds radiators or the like |3 through valves l2, the condensate being returned by a pipe I4, in which are two non-return valves l5, 6. Between the two nonreturn valves, a branch pipe I! communicates with the bottom of the chamber of the apparatus l3 to the top of which are connected a steam pipe I9 communicating with pipe and an atmospheric vent 20.

The apparatus l8 (see Figure 2) comprises a cylindrical float-chamber 2|, into the bottom of which pipe I! opens, and which encloses afloat 22. The top of the chamber 2| is closed by a the steam pipe l9 and with the atmospheric vent 20. One face of the valve-body is provided with a removable inspection "cover 63 (see also Figure 4) the top of the ifloat 22 (see Figure 3) is mounted asocket 24 having vertically slotted openings T25iaccommodating a bolt 23, which passes throug a block-21, into which is screwed the lower end of a vertical rod 23, The latter extends upwardly through a guide 23 screwed into the base bi the valve-body '23. Openings some the 'baseili (see Figure 4) provide free communication between the interior of the float er '2] and the interior of the valve body. The u per 'end of 'rod 128 is screwed into aboss 3| having inclined i f'aces 3V which engage, with easy 'clea'r'ance, opposed mating faces 32 of an 'opehi g in a transverse valve-member 32 termiinatihg at both ends in needles 33 which enter self-seating 'th'imbles 34 having conical ends.

which are screwed into'valve-pockets 31. If the seating iaces 35'wear out of true, the thimbles 34 accommodate themselves to them and maintain "a good seal. "The valve-pockets" 31 are internally-threadedint'o the valve-body 23 and have screwed necks 33,319, which receive, respectively, the pipes 13, 20 (see Figure 2). The valvepockets 3! arealsb provided with screw plugs '40, removal of which gives a'ccess'to the seatings 36 for inspection, adjustment or removal. The inner ends of the valve-pockets '31 extend into the valve-body and are provided with ports 4| which afford communication between the bores of the valve-pockets and "the interior of the valve-body 23jbiit can "be obstructed by the sliding valve member '32. The valve-member '32 slides in the bores of the valve-pockets 3! in which it is'agood sliding fit.

When the float 22 rises, the inclined faces of block-3| move the member 32 to the left, as seen in Figure 3, bringing the lef-t- -hand thimble34 onto its seatingand closing the left-hand set of ports 4|, the right-hand thimble being freed to leave its seating and the right-hand ports 4| being uncovered. This admits steam from pipe l9 to the float-chamberZL 'When the float falls.

the member 32 is moved to the right closing the right- hand needle valve 34, 35 and right-hand ports 4| and opening the left- hand needle valve 34, 35 and left-hand ports 4| as shown in Figures 3 and 4. This cuts ofi the steam from pipe I9 and opens the float-chamber to atmosphere through the vent 20.

It will be seen that both the steam admission valve and the atmospheric vent valve comprise needle valves 34, 35 and piston valves 32, 4| arranged in series. The piston valve components ensure that full admission of steam or full release to atmosphere cannot take place until the valve member 32 is thrown over to its full extent in one direction or the other. The needle valves 34, 35 provide an eff cient seal when the combined valve is closed.

It will also be noticed that the components of the steam admission valve including the valve pocket 31, seating 33, thimble 34 and screw plug 43 are identically similar to the corresponding means of which the spring tension maybe ad justed and which are protected by screwed caps balls 4 Qt? 9 7 .552? a ds. q'li l' tally by the springs to engage one or other of a pair of circumferential grooves 50%,5-0 -o-f a cap to which is screwed onto the upper end oi an extension rod 42 whose lower end is screwed-into the block in s im s h't e od- 5 i-he rod 42 slides in a :guide 4 3 screwed into the'base of the bracket 44 and into the top of the-valve body 23. The cap-501s provided with an-extenm rod h 'i ide n a b idg f ie efi secured to the top of the standards 44 and 44.

" The extension rod '42 is provided wi-th conical seating collars -6 seaton conical faces at the top and bottom of the guide 43 whensthe float Z2 and the P r sup e d the ebv are in their l a h hest P s io s emedies- The t i h sp in s are a usted o that when the halis 45 are-engaged with the-lower groove 50 0f the cap 50,]the springs 4-7 will n yield and al w hefi a 22 t a un ess. he float-chamber'fl is empty of liquidgirve. so, :long a there 1 m. browser to el ve t we g t suspended on the ball catch t he latter';wi;l-l not yield allow the fl a to dro Simila l h h be s, re e age w t the u per groove 50 of the cap 50, the springs 41 will not yield andallow the float22=to rise until the-float-, chamber "2| .is full enough completely -to submerge the .float and the float experiencesthe maximum buoyancy effect of th contair eddiquid. It will be evident that the cri-tical v ertical load on the cap 50 at which the balllcat ch will yield must be -thesam'e whetherappliednpwarde ly or downwardly, and consequentlytthefloat 2 must be so weighted in relation toits buoyancy h the, total ht u n ed n the a it when the floatchamber ,isempty isequal to, the buoyancy of the 'float when completely submerged less the weight-of the float and the parts supported by it. 1 '7 The apparatus above describedoperateaas rfol lows; Referring to li'igures s1 and2,-condensete draining down the pipe l4 passes the non-return valve I5 and enters the bottom of the floatchamber 2| of the apparatus |8 through the branch pipe ll. When sufiicient condensate has accumulated in the float-chamber 2| to submerge the float 22 completely, the latter rises from the position shown in Figure 3 sufficiently to engage the balls 45 with the lower groove 5|) of the cap 50. In risin through this distance, the inclined faces of the block 3| throw the transverse sliding valve member 32 over from right to left, as seen in Figure 3. This allows the thimble 34 of the steam valve on the right of Figure 3 to leave its seating 35 and uncovers the ports 4| of the steam valve, at the same time closing the ports 4| of the atmospheric vent valve on the left of Figure 3 and bringing the thimble 34 of this valve onto its seating. In this movement, the ports 4| of the steam valve are not fully uncovered until the needle valve 34, 35 controlling the atmospheric vent is closed. This movement of the parts admits live steam from the pipe l9 through the steam valve into the valve body and thence through the openings 3|] into the float-chamber, the liquid contents of which are returned through the branch I? and the non-return valve 5 back into the boiler. The opening of the steam valve communicating with the pipe l9 equalises the pressures above and below the contents of the float chamber, and the return of the contents of the float-chamber to the boiler is efiected by gravity due to the head provided by mounting the ap paratus I8 at a level above that of the boiler.

As soon as the float-chamber is emptied, the float 22 is released by the ball catch 46 and falls again, throwing the valve member 32 over to the right, the parts being returned to the position shown in Figure 3, thus closing the steam inlet valve and opening the atmospheric vent valve and allowing the excess steam to escape through the ports 4| and valve 34, 35 to the atmospheric vent 20, the pressure in the float-chamber being again reduced to atmospheric.

This cycle continues to repeat itself, the ball catch 45 ensuring that the valve member 32 is thrown over smartly in alternate directions when the float chamber becomes full and empty, respectively.

The ball catch 46 may be replaced by the modiflcation illustrated in Figures 5 and 6 in which the extension rod 42 carries a collar 53 secured in fixed position on extension rod 42 by nuts 54, the collar 53 being connected by hinged toggle links 55 with plungers 56 sliding horizontally in housings 5'! secured to the standards 44 and 44 respectively, and enclosing springs 58 retained by adjustable screw plugs 59, the latter being protected by screw caps 60. This arrangement gives a positive upward or downward force on the float and parts supported thereby in all intermediate positions of the float between the highest and lowest position. This is advantageous, especially when the apparatus is required to operate in a high-pressure steam system carrying a working pressure of 150 lbs. or more. In such a system, the condensate on entering the float chamber, which is at atmospheric pressure, releases large quantities of steam owing to the drop of pressure, and if, as normally occurs, the condensate enters the float chamber faster than this steam can be released, the condensate level may rise sufficiently to initiate the lifting of the float and then fall again owing to release of steam before the float has risen fully. With the ball-catch type of float-control there is then. no extraneous force tending to complete the rising of the float. which may stick half-way between its extreme position and be held there by the balls engaging the collar 5B frictionally between the grooves 50*, 50 The steam valve is thus held half-open giving partial admission of steam to the float-chamber sufiicient to prevent the entry of further condensate but insufficient to empty the chamber of condensate. The positive action of the togglemechanism effectively prevents this type of failure. However, with more moderate steam pressures, the ball catch is found to be effective and reliable and the apparatus is not subject to the type of failure discussed above.

I claim:

1. An apparatus for collecting condensate from a steam circulating system and returning the same to the boiler comprising a chamber having spaced, relatively opposite inlet and outlet openings at the upper portion thereof, said inlet openin adapted for connection to a source of steam and said outlet opening adapted to vent said chamber to atmosphere, said chamber also having a branch pipe at the lower portion thereof communicating with the interior of said chamber, one branch of said pipe adapted for connection with a pipe for conducting the condensate from the system into said chamber, said last named pipe having a non-return valve therein permitting condensate to pass through said one branch and into said chamber, and the other branch of said pipe adapted for connection with a pipe for conducting the condensate from the chamber back to the boiler, said last named pipe having a non-return valve therein permitting the condensate to pass from said chamber back to the boiler; a slidable valve member mounted for reciprocation between the spaced, relatively opposite inlet and outlet openings and having valve means on the ends thereof adapted to alternately open and close said inlet and outlet openings; a float within said chamber adapted to rise or descend in accordance with the presence or absence, respectively, of condensate within said chamber; and a member connected to said float and movable therewith in a direction normal to the direction of movement of said valve member, said valve member and the member connected to said float having cooperating, slidably engaging, substantially parallel faces inclined obliquely to a vertical plane perpendicular to the line of movement of said valve member, the direction of inclination of said cooperating faces bein such that the valve member is reciprocated in a direction to open the inlet valve and close the outlet valve when the float rises and to close the inlet valve and open the outlet valve when the float descends.

2. An apparatus as defined in claim 1 in which the inlet and outlet openings each include axially disposed and radially disposed openings with the radially disposed openings spaced inwardly with respect to the axially disposed openings, and wherein each end of the valve member includes a needle-type valve adapted to seat on the axially disposed opening adjacent that end of the valve member and a piston-type valve adapted to control the radially-disposed openings adjacent said end of said valve member.

3. An apparatus as defined in claim 1 in which the inlet and outlet openings each include an inwardly-facing valve seat, and wherein each end of said valve member has loosely secured thereto a sonically-ended thimble whichseats on an ad- J'acent valve seat self -adjustably when said valve member is moved to. valve closing position with respect to said adjacent valve seat,

4. An apparatus as. defined in claim '1 in which a spring loaded means engages the member connected to the float and movable therewithior yieldingly retaining thefloat in its uppermost and lowermost positions, said spring loaded means yielding and permitting the float to rise only when the chamber containing the. flo t is substantially full of condensate, and permittin the float to descend only when the said chamher is substantiall empty.-

.5. .An apparatus as defined in claim 1 in which the member connected to the float has upper. and lower, spaced, circumferential grooves thereon, and in which a spring loaded ball catch frictionallyengagesv one or the otherofsaid grooves,

. said catch yieldingly retaining the float in its uppermost and lowermost positions by engagement with saidupper or lower grooves. IGSpgCr tively. said catch yielding to disengage. the upper roove and permit the float to rise only when he chamber conta ning the :float is substantial y fu of. cond h teran yi ldin to disen a e the wer roove and perm t. the float. to descend nly whe he said chamber is sub tantially mp yapparatus as defined-in ci irni in which t e m m r c nnected to the noatand movable er wi h ha a collar thereon connected by ed, to gle links t snriheelcad d p oneer s hksehd prin -l aded pioneer ese his Pesitive upwardor downward threes i al i mediate i ns o the that b tween i s. u e most and lowermost positions,

7-. h @Phhthtus hseefine in clai whi h e ead d nsane c eeses. the membe 9 h: heeted o h a and mo ab e therewl h. i s v s d he y inin he flee u ermost and low mos posit o s id sh me y in nd r hshehe t o th n w e chamber t substantially pull or den the h to es n o v e sa d chamhe s s bs an ia l empt and; whi th weight o e l at and. parts su p rt t eby is a ste w th rela -to the hhh hey f the f oa e athe h tuswar th ee exerted on the spr g, o ded means wh n the ch m e is ub-. ti y u o o densateisee al to the d wnd fierc e ert 0. .1 the h ne loaded mean w n t fl a c amb r s stantia l e 8. An apparatus for collect r condensate iron: a steam circulat s stem and ret he th m to h bo le comp is ng a chamber hav n sp d relatively op osite mist and outlet o eni e at the upper po ti n thereoi; said i let p r ing adapted for connection to asource of steam and said tl openin ada ted to vent said chamber to atmosp e e sa d chambe also nay-.- ing a branch pi e at the lower portion thereof ica in wit heinter cr of aid ch r one b a h o .seidr neadapted or on tion w a p e for c nd tin the condo. r the sy m o said chamber aid last am p p hav ng a vnenzreturn valve there n e m n n en ate to pass throu h said branchv into. sai chambe and the o he bra c f s p dapt. for conn ct-ion with a pipe r conducting the conden at i em th chamber back to th oiler sa d"las named pipe ha a hen-re n v lv the permi t n the c e ate p ss from said chamber back to th boi e s idshl va e inemherrm unted tor reciprocationbetwehn .isn eedarelanvelr on posite inlet and outlet openings and having valve means on the ends thereof adapted to alternately open and close said inlet and outlet openings, said valve member being provided intermediate the ends thereof with an opening defined by walls including spaced, substantially parallel end walls inclined obliquely to a vertical plane perpendicular to the direction of movement of said valve member; a float within said chamber adapted to rise or descend in accordancewith the presence or absence, respectively, of condensate within said chamber; and a member connected to said float and movable therewith, said member passing through the opening in said valve member and having spaced, parallel walls mating and slidably. engaging the. inclined end walls of the opening in the valve member, the direction of in-.- clination .of said spaced end walls and said mating walls being such that the valve member is reciprocated in a direction to open the inlet valve and close the outlet valve when the float rises and to close the inlet valve and open the outlet valve when the float descends.

9.. An apparatus for collectingcondensate from a steam circulating system and returning the same tothe boiler comprising a vertically disposed tubular chamber; a valve body secured to the top of said chamber and enclosing a space communicating with the interior. of said chamber; two valve pockets secured, respectively, to one side and to the other side of said valve body and extending thereinto in communication with said space and at relatively opposite locations, one of said pockets adapted for connection to a source of steam and the other to vent said chamber to atmosphere; a branch pipe at the lower portion of said chamber and communicating with the in-- terior of said chamber, one branch of said pipe adapted for connection with a. pipe for conducting the condensate from the system into said chamber and having a non-return valve therein, and the other branch of said pipe adapted for connection with a pipe for conducting the condensate from the chamber back to the boiler and having anon-return valve therein; a slidable valve member including a needle-type valve on each end thereof and mounted within saidvalve body for reciprocation between the relatively op.- posite valve pockets; each of said valve pockets including a valve seating portion having coaxially extending bores with an axially and inwardly directed valve seat intermediate said bores, the innerend. of each valve seating extndinginto the space within the valve bodyan-d having radially extending ports through'the wall thereof communicating with said space, the bore within said inner .end .of each valve member having a sliding fit with and providing a sliding support or one end of the vslidable valve member, said radiallyextending ports cooperating with the end portions of the slidable valve memberto constitute piston-type valve means, and the valve seatintermediate the ends of each .pairof coaxial-bores cooperating with the needle-type valve at the ends of said slidable valve member toconstitute needle-type valve means; a float within said tubular chamber adaptedtoriseor descend in accord.- ance Wi h the presence ,or absence, respectively, of condensate within said chamber; and a memberponnectfid to said float and movable therewith for moving said slidable valve member a direction to open the needle-type valvemeansandthe piston-type valve means in the valve pocket ad pted for connection to .a' sourceofsteam and to. close the .needlettype valve means and-themes.

ton type valve means in the opposite valve pocket upon rise of said float within said tubular chamher, and for moving said slidable valve member in the opposite direction to open the needle-type and the piston-type valve means in the valve pocket adapted to vent said tubular chamber to atmosphere and to close said needle-type and piston-type valve means in the opposite valve pocket upon descent of said float within said tubular chamber.

10. An apparatus as defined in claim 9 in which a separate sleeve member is adjustably screwed into the outer end of each pair of the coaxial bores in each valve pocket, and in which the inner end portion of each sleeve member includes the valve seat intermediate the ends of each pair of coaxial bores.

FREDERICK STANLEY MOB-TON.

10 REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 1,161,554 Voigt Nov. 23, 1915 1,233,450 Cookson July 17, 1917 1,252,967 Trane Jan. 8, 1918 1,326,944 MacDonald Jan. 6, 1920 1,910,060 Rose May 23, 1933 1,925,610 Shinn Sept. 5, 1933 2,431,936 Hudson Dec. 2, 1947 FOREIGN PATENTS Number Country Date 2,431 Great Britain of 1874 29,040 Great Britain of 1897 330,447 France Aug. 19, 1903

Images