SI9011965A

SI9011965A - Fitting, particularly for tight joints of small diameter plastic and metal pipes

Info

Publication number: SI9011965A
Application number: SI9011965A
Authority: SI
Inventors: Laszlo Juhasz; Tibor Vass
Original assignee: Kozepdunantuli Gazszolgaltato
Priority date: 1990-10-18
Filing date: 1990-10-18
Publication date: 1997-12-31
Also published as: YU196590A

Description

Kozepdunantiili Gazszolgaltato Vallalat Nagykanizsa/MadžarskaKozepdunantiili Gazszolgaltato Vallalat Nagykanizsa / Hungary

Fiting, predvsem za tesno priključitev plastičnih in kovinskih cevi majhnega premeraFittings, especially for tight connection of small diameter plastic and metal pipes

Področje tehnikeThe field of technology

Predmetni izum se nanaša na cevovode, bolj konkretno na take iz polimerov.The present invention relates to pipelines, more specifically to polymers.

Na veliko uporabljane cevi iz polimerov (PVC, polietilena, polipropilena) dandanes najdemo v zelo raznovrstnih napeljavah, tako denimo v oskrbovalnih (voda, plin), v stanovanjski gradnji (talno ogrevanje) in na splošno povsod tam, kjer je treba tlačne fluide transportirati ekonomično, estetsko in zanesljivo. Za uporabo cevi iz polimerov je tudi značilno, da so cevi odporne na različne obrabne dejavnike, ne da bi jih bilo treba površinsko kako posebej obdelati, da se jih zlahka in hitro sestavljati, pretočni upor je majhen in ne vnašajo dodatnih napetosti.The widely used polymer pipes (PVC, polyethylene, polypropylene) are nowadays found in a wide variety of installations, such as in supply (water, gas), in residential construction (underfloor heating) and generally where pressure fluids need to be transported economically , aesthetically pleasing and reliable. The use of polymer tubes is also characterized by the fact that the tubes are resistant to various wear factors, without having to be specially treated to be easily and quickly assembled, the flow resistance is small and does not introduce additional stresses.

Normalno je, da se polimerne cevi povezujejo z vsakdanjimi kovinskimi zasuni, pipami, ventili, na splošno s kovinskimi fitingi in kovinskimi cevmi.It is normal for polymer pipes to be connected to everyday metal valves, taps, valves, generally metal fittings and metal pipes.

To pa ni majhen problem, saj priključevanje polimernih cevnih delov h kovinam ni izvedljivo z neposrednim varjenjem, kot je znano dandanes. Z navoji opremljene kaljene ali tlačno lite spojke vrste distančnik pa vedno ne zadoščajo sodobnim zahtevam.This is no small problem, since the connection of polymer tubing to metals is not feasible by direct welding, as is known today. However, threaded or pressurized cast spacer couplings do not always meet modern requirements.

Tehnični problemA technical problem

Tehnični problem, ki se rešuje s predmetnim izumom, je, kako ustvariti izboljšan fiting, ki ne škoduje pretočnemu preseku, a ohrani tesnost in trdnost zveze ter njeno toplotno odpornost, s tem da je sestavljanje na kraju samem enostavno, izdelavna cena nizka in da ni nikakršnega vpliva na tok medija.The technical problem to be solved by the present invention is how to create an improved fitting that does not damage the flow section, but maintains the tightness and strength of the joint and its thermal resistance, making assembly on-site easy, low cost of production and no no effect on the flow of the medium.

Stanje tehnikeThe state of the art

Sestavljena cevna zveza, vsebujoča polimerne in kovinske dele, mora biti zdržljiva. To je temeljnega pomena, saj se lastnosti polimerov sčasoma menjajo, tako da je treba, s tem ko poznamo popuščalno vedenje polimerov, to upoštevati, ko sestavljamo zvezo. Splošna zahteva je, da so vse fizikalne lastnosti zveze blizu podobnim lastnostim polimerne cevi.The assembled pipe joint containing the polymer and metal parts must be durable. This is fundamental because the properties of the polymers change over time, so that, knowing the yielding behavior of the polymers, this must be taken into account when forming a union. It is a general requirement that all physical properties of the joint are close to similar properties of the polymer tube.

Za realizacijo zadevne zveze je znanih več načinov, o čemer je govor v nadaljnjem.There are several ways of realizing the union in question, which are discussed below.

Tlačno lit vezni profil ima element z navojnim ali privarljivim nastavkom na strani, kjer se priključi jekleni del, stranski polimerni profil pa je tlačno prilit k njegovemu osrednjemu utornemu odseku. Zveza je prednapeta in okrepljena z obročem, nataknjenim z zunanje strani ali izdelanim s tlačnim litjem v enem kosu. S polimerno stranjo se lahko veže na znan način z varjenjem (čelni, tulčni zvar).The die-cast connection profile has an element with a threaded or welded attachment on the side where the steel part is connected, and the lateral polymer profile is pressurized to its central groove section. The connection is prestressed and reinforced by a ring tucked in from the outside or made by pressure casting in one piece. It can be bonded to the polymer side in a known manner by welding (front welding).

Pomanjkljivost tlačno litega veznega profila je, da vnaprej pripravljeni kos z varjenjem priključijo na kraju samem, kar je drago in ne zadosti zanesljivo, ker so posredi subjektivni vplivi. Po našem dosedanjem spoznanju kakovost polimernega varjenja na kraju samem ni primerna.The disadvantage of a die-cast connection profile is that they pre-assemble the pre-welded piece with spot welding, which is expensive and not reliable enough because they are subjective influences. To our knowledge, the quality of on-site polymer welding is inappropriate.

Tlačno lit vezni profil so v čedalje večji meri nadomeščali s postopki prilagajanja profila, s čimer so odpravili varjenje na kraju samem in omogočili hitro prilagajanje.The die-cast connection profile has been increasingly replaced by profile adjustment procedures, eliminating on-site welding and facilitating rapid adjustment.

Profil iz znanega postopka sestoji iz dveh delov - notranjega posnetega tulca, opremljenega z navojem za povezavo s cevnim delom, in zunanjega zategovalnega koničnega tulca. Cevni konec, prilagodno vložen v tulec, se fiksira z zategovalnim koničnim tulcem, vtisnjenim v luknjo cevi, tako da se gradivo cevi vrne nazaj v utore posnete notranje površine tulca. Stisnjenje se opravi z enim samim namenskim orodjem.The profile of the known process consists of two parts - an inner skeleton sleeve fitted with a thread for connection to the tubular part and an external tightening conical sleeve. The tube end, which is flexibly inserted into the sleeve, is fixed by a tightening conical sleeve inserted into the tube hole so that the tube material is returned back to the grooves of the recorded inner surface of the sleeve. Compression is done with a single dedicated tool.

Pomanjkljivost zgornjega postopka je, da zategovalni konični tulec zmanjša pretočni presek, medtem ko konstrukcija dopušča vgrajevanje samo cevnih kosov, ki so po nepotrebnem večji od imenskega premera cevi. Deformacija, do katere pride med sestavljanjem, je odvisna v glavnem od globine vstavitve koničnega tulca in izdelovalne natančnosti elementov. Položaj zategovalnega koničnega tulca v zvezi je naključen.The disadvantage of the above procedure is that the tightening conical sleeve reduces the flow cross-section, while the construction allows the installation of only pipe pieces that are unnecessarily larger than the nominal pipe diameter. The deformation that occurs during assembly depends mainly on the depth of insertion of the conical sleeve and the manufacturing accuracy of the elements. The position of the taper cone tightening in relation is random.

Zveza, kakršno dandanes v splošnem uporabljajo, vsebuje dva posneta profila, podobno onemu od prej, toda tu je notranji zategovalni konični tulec ožlebljen, zunanji posneti kos pa vtisnejo s pomočjo z matičnim navojem zasnovanega veznega kosa in uvitega kosa, ki oklepa zvezo. Takšna je denimo zveza, ki jo na trgu poznamo pod imenom Banides-Debeaurain.The joint, as it is generally used today, has two tapered profiles, similar to the one before, but here the inner taper cone is grooved and the outer tapered piece is stamped with the help of a threaded design of the bonded piece and a twisted piece that surrounds the connection. Such is the connection known in the market as Banides-Debeaurain.

Ta zveza je razstavljiva in vsebuje običajna spenjala. Njena opazna pomanjkljivost je, da obsega, ker je tesnjenje zasnovano na posebnem O tesnilu, vsaj pet delov. Tudi ta postopek zmanjša pretočni presek, dolžina za spenjanje polimerne cevi pa je konstrukcijsko omejena.This connection is disassembled and contains conventional fasteners. Its noticeable disadvantage is that it comprises at least five parts because the seal is based on a special O seal. This process also reduces the cross-section and the length of the polymer pipe clamping is limited in design.

Nerazstavljiva cevna zveza je denimo tista, ki jo na trgu poznamo pod imenom Georg-Fischer. Deformacija, do katere pride v steni cevi, ki jo obdajajo valjasti deli zveze, je združena s tlačno napetostjo, katere rezultat je torni upor med kovinskimi in polimernimi površinami pod obtežbo.An indivisible pipe connection, for example, is one known on the market under the name Georg-Fischer. The deformation occurring in the pipe wall surrounded by the cylindrical members of the joint is compounded by the compressive stress, which results in a friction resistance between the metal and polymer surfaces under load.

Površino profila, ki oklepa cev, prekinjajo U utori, da se poveča površinski pritisk.The profile surface surrounding the pipe is cut off by the U grooves to increase the surface pressure.

Prednost zveze je, da dva dela sestojita iz sorazmerno preprostih elementov, katerih vgrajevanje je hitro. Po drugi strani pa je njena pomanjkljivost, da notranji element moti tok in razen tega - saj vemo, da polimeri sčasoma popuščajo - spontana oslabitev zveze ni izključena. Razlog za to je, da se zveza skupaj drži praktično le s silo proti osni sili, ki jo povzročata težnja po izvlečenju in notranji nadtlak, tlačna napetost, ki ustvarja torno silo (silo blokiranja), pa sčasoma popusti. Do zmanjšanja te tlačne napetosti pride še hitreje, če naraste temperatura okolice, saj je za polimere značilno, da do sprememb prihaja bodisi po spremenljivki temperatura ali spremenljivki čas. Ohlapna zveza zgublja tlačno trdnost, zaradi česar postane netesna.The advantage of the connection is that the two parts consist of relatively simple elements, which are quickly installed. On the other hand, its disadvantage is that the internal element disrupts the flow and, moreover, because we know that the polymers eventually loosen, spontaneous weakening of the bond is not excluded. The reason for this is that the joint is held together by virtually only the force against the axial force caused by the tendency to pull out and the internal overpressure, and the compressive stress that generates the friction force (blocking force) eventually declines. The decrease in this compressive stress is even faster when the ambient temperature rises, since polymers are characterized by changes either by temperature or by time. A loose union loses compressive strength, making it tight.

Cilj pričujočega izuma je odpraviti zgoraj navedene pomanjkljivosti, t.j. ustvariti izboljšan fiting, ki ne moti pretočnega preseka, s tem daje ohranjena tesnost zveze.It is an object of the present invention to remedy the above disadvantages, i.e. to create an improved fitting that does not interfere with the flow cross-section, thereby maintaining the bond tightness.

Opis rešitve tehničnega problemaDescription of solution to a technical problem

Izum temelji na spoznanju, da je v zadevi izdelave primerne zveze kovinskega in polimernega dela treba poskrbeti za primerno napetost v vpetem cevnem koncu ob nadzorovani deformaciji. V ta namen je zveza tako v pogledu zdržljivosti kot tudi tesnosti dimenzionirana ob upoštevanju časovno odvisnih sprememb polimerov. Pri reševanju problema smo uporabili sodobna načela gradnje, zlasti koncentracijo funkcij in porazdelitev obtežbe, t.j. princip, da se z naraščanjem obtežbe veča upor. Zveza, dobljena s to konkretno konstrukcijo, je trajna, oblikosklepne in silosklepne značilnosti pa se upirajo tako izvlečenju kot tudi notranjemu nadtlaku. Zveza ne posega v pretočno polje in tudi ne moti toka medija. Zveza terja minimalno količino gradiva in živega dela.The invention is based on the realization that in the matter of making a suitable union of the metal and polymer part, it is necessary to provide suitable tension in the clamped tube end with controlled deformation. To this end, the bond is dimensioned both in terms of durability and tightness, taking into account the time-dependent changes of the polymers. We used modern construction principles to solve the problem, especially the concentration of functions and the distribution of the load, i.e. the principle that resistance increases with resistance. The connection obtained with this particular construction is durable, and the shape-locking and silo-locking characteristics resist both extraction and internal overpressure. The connection does not interfere with the flow field and does not interfere with the flow of the medium. The union requires a minimal amount of material and live work.

Napetostno in deformacijsko stanje, potrebno po izumu, se vzpostavi z vtaknjenjem konca polimerne cevi med dve valjasti tulčasti kovinski telesi. Elastična togost zunanjega tulca je večja od tiste, ki jo ima notranji, in njegova površina, ki se dotika cevi, je opremljena s posebnim utorom. Ta utor je osnova za silosklepno in oblikosklepno zvezo, hkrati pa ustvarja tesnilni pritisk. S tem je izpolnjen pogoj koncentracije funkcij. Utor pa ima še nadaljnjo tesnilnotehnično funkcijo: tlačne stopnje si sledijo zaporedoma po odsekih (med utori), tako da se tlačni padec manjša od stopnje do stopnje.The tensile and deformation state required by the invention is recovered by inserting a polymer tube end between two cylindrical tubular metal bodies. The elastic stiffness of the outer sleeve is greater than that of the inner sleeve, and its surface which contacts the tube is provided with a special groove. This groove is the basis for the silo-and-sine joint, while creating a sealing pressure. This fulfills the condition of concentration of functions. The groove has a further sealing function: the pressure stages are followed sequentially by sections (between grooves) so that the pressure drop is smaller from stage to stage.

Stanje s tlačno napetostjo in nujno deformacijo stene cevi je doseženo s trajno deformacijo notranjega tulca. Ker ima notranji tulec nižjo elastično togost od tiste, ki jo ima zunanji, se da naključno zmanjšanje napetosti v zvezi popraviti s pomočjo elastične deformacije prednapetega notranjega obroča.The condition with compressive stress and the necessary deformation of the pipe wall is achieved by permanent deformation of the inner sleeve. Since the inner sleeve has a lower elastic stiffness than that of the outer one, it can be accidentally reduced by the elastic deformation of the prestressed inner ring.

Ta učinek se ojača s pomočjo viskoelastičnega vedenja polimernega gradiva, ki zleze v utore: elastična deformacija materiala, ki je zlezel v utore, popravi zmanjšano tlačno napetost stene cevi s pomočjo zmanjšane lokalne deformacije.This effect is amplified by the viscoelastic behavior of the polymer material that creeps into the grooves: the elastic deformation of the material that creeps into the grooves corrects the reduced compressive stress of the pipe wall by means of reduced local deformation.

Notranji tulec (vključno zvezo) deformiramo z razširitvijo tulca do potrebne velikosti na znan način, najbolje s pomočjo vlečenja kalibrirnega koničnega telesa skozenj. Ta način razširjanja je primeren, kajti z njim ne le dosežemo trajno deformacijo tulca, ampak se ohrani elastična deformacija. Nadaljnja dobra lastnost je, da je načrtovana zveza v manjši meri odvisna od subjektivnih napak.The inner sleeve (including the union) is deformed by extending the sleeve to the required size in a known manner, preferably by pulling the caliber conical body through it. This expansion method is suitable because it not only achieves permanent deformation of the sleeve, but also maintains elastic deformation. A further good feature is that the planned relationship is less dependent on subjective errors.

Izum je spodaj opisan v podrobnostih ob pomoči priloženih skic, ki kažejo primer praktične izvedbe predlagane rešitve po izumu. Pri tem kažejo:The invention is described below in detail with the aid of the accompanying drawings showing an example of the practical implementation of the proposed solution according to the invention. In doing so, they show:

sl. 1 dva dela fitinga v razstavljenem stanju z zgornjo polovico v osnem prerezu, spodnjo v narisni projekciji, sl. 2 cevno zvezo, ki vsebuje fiting s sl. 1, v sestavljenem stanju, prav tako z zgornjo polovico v osnem prerezu in spodnjo v narisni projekciji, in sl. 3 detajl A s sl. 1, seveda v večjem merilu.FIG. 1 shows two parts of the fitting in the disassembled state with the upper half in axial section, the lower in the outline projection, FIG. 2 is a pipe connection comprising the fitting of FIG. 1, in the assembled state, also with the upper half in axial section and the lower half in outline projection, and FIG. 3 is a detail A of FIG. 1, of course on a larger scale.

Kot kaže skica sl. 1, fiting B po izumu sestoji iz kovinskega dela 1 in tankostenskega kovinskega tulca 2. Del 1 ima valjasti luknji 4, 9 in med njima mejno obročasto stopnico 3.As shown in FIG. 1, fitting B according to the invention consists of a metal part 1 and a thin-walled metal sleeve 2. Part 1 has cylindrical holes 4, 9 and a boundary annular step 3 between them.

Valjasta luknja 4 sprejme zunanjo plaščno površino plastične cevi 15 in je zato njen premer tako izbran, da je upoštevana stopnja prednapenjanja, pri čemer je v luknjo 4 vdelan niz utorov C, da je izvlečenje preprečeno tako s silo kot tudi z obliko, in da je tudi poskrbljeno za potrebno tesnilno silo.The cylindrical hole 4 adopts the outer jacket surface of the plastic tube 15 and, therefore, its diameter is so chosen that the degree of prestressing is taken into account, with a series of grooves C being embedded in the hole 4, so that it is prevented by both force and shape, and that also provided the necessary sealing force.

Število utorov je izbrano v odvisnosti od porazdelitve sile in pritiska utorov C, ki so razporejeni z delitvijo 8 in dimenzionirani z globino 7. Zaobljenost 5 dna utorov in vrhovi 6 med njimi poskrbijo za potrebno deformacijo polimerne cevi 15.The number of grooves is selected depending on the force distribution and pressure of the grooves C, which are divided by division 8 and dimensioned by depth 7. The curvature of the 5 bottom grooves and the peaks 6 between them provide the necessary deformation of the polymer tube 15.

Luknja 9 je po premeru enaka zunanji plaščni površini 10 tankostenskega kovinskega tulca 2, da je zagotovljeno preprosto nameščanje plastične cevi in stikanje konca le-te s prirobo 11 kovinskega tulca 2.The hole 9 is identical in diameter to the outer jacket surface 10 of the thin-walled metal sleeve 2, to ensure easy placement of the plastic tube and to connect the end thereof with the flange 11 of the metal sleeve 2.

Zunanja površina dela 1 fitinga je opremljena z zunanjim navojem 12 za vijačno povezavo s kovinsko cevjo. Da se olajša sestavljanje, je del 1 fitinga opremljen s profilom 13, tu šestkotnim profilom, primernim za poseg z orodjem. Premer zunanje površine 14 dela 1 fitinga je določen s potrebno velikostjo preostale debeline stene.The outer surface of part 1 of the fitting is provided with an outer thread 12 for a screw connection to the metal pipe. To facilitate assembly, part 1 of the fitting is provided with a profile 13, here a hexagonal profile suitable for tool engagement. The diameter of the outer surface 14 of part 1 of the fitting is determined by the required size of the remaining wall thickness.

V cevni zvezi (sl. 2), narejeni s priključljivim fitingom B po sl. 1, je pretočni presek (luknja 16) razširjenega notranjega kovinskega tulca 2 enak pretočnemu preseku (luknji 17) priključljive plastične cevi 15. Skica sl. 2 jasno kaže, da je priključeni konec polimerne, npr. PVC- cevi 15 malenkostno razširjen, tako da tvori prirobo 11, ki jo z zunanje strani obdaja notranja luknja 4 dela 1 fitinga, torej luknja, ki ima utore C, medtem ko jo z notranje podpira zunanja plaščna površina 10 kovinskega tulca 2, tako da v celoti obstaja tesnost, dosežena s silo in obliko.In the pipe connection (Fig. 2) made with the connecting fitting B according to Figs. 1, the flow cross-section (hole 16) of the expanded inner metal sleeve 2 is equal to the flow cross-section (hole 17) of the connecting plastic pipe 15. FIG. 2 clearly shows that the connected end of the polymer, e.g. The PVC pipe 15 is slightly expanded to form a flange 11, which is surrounded externally by the inner hole 4 of the fitting part 1, i.e., the hole having grooves C, while it is supported internally by the outer jacket surface 10 of the metal sleeve 2, such that entirely there is a tightness achieved by force and form.

Sl. 3 jasno kaže povečane utore C luknje 4 dela 1 fitinga. Vsakokratni utor C je omejen z zaobljenostjo 5, vrhom 6 in vmes nahajajočima se bočnima ploskvama, ki v ravnini v osnem prerezu medsebojno oklepata kot -γ velikosti 75°. V tem konkretnem primeru razmerje dolžina/premer luknje 4 znaša 3:2. Predvideva se 18 do 24 utorov C. Razmerje globine 7 utorov proti delitvi 8 v tem primeru znaša 4:10.FIG. 3 clearly shows the enlarged grooves of C hole 4 of part 1 of the fitting. Each groove C is bounded by a rounded 5, apex 6, and laterally located lateral planes, which in the plane in axial cross-section are mutually enclosed as -γ of size 75 °. In this particular case, the length / diameter ratio of hole 4 is 3: 2. 18 to 24 grooves are foreseen C. The depth ratio of 7 grooves to split 8 is 4:10 in this case.

Kovinski tulec 2 je vsaj za 10% daljši od z utori opremljene luknje 4 dela 1 fitinga. V tem primeru razmerje debeline stene kovinskega tulca 2 proti premeru njegovega zunanjega plašča 10 znaša 8:100.The metal sleeve 2 is at least 10% longer than the grooves of the fitting hole 4 of part 1 of the fitting. In this case, the ratio of the wall thickness of the metal sleeve 2 to the diameter of its outer jacket 10 is 8: 100.

Kovinski tulec 2 v cevni zvezi (sl. 2) lahko radialno razširimo na znan način.The metal sleeve 2 in the pipe connection (Fig. 2) can be radially expanded in a known manner.

Po pooblastilu: Patentna pisarna, d.o.o. Zanjo: Vinko SkubicBy mandate: Patent Office, d.o.o. For her: Vinko Skubic

Claims

Patent claim

A fitting, in particular for the tight connection of small diameter plastic and metal pipes, characterized in that it has a long metal part (1) and a cylindrical cylindrical cylindrical sleeve (2), with the first-mentioned fitting part (1) being formed by two , preferably coaxial cylindrical holes (4, 9) of various diameters and having a boundary annular step (3) between them, wherein the ratio of the length / diameter of the larger diameter hole (3) is 3: 2 and grooves (4) are located along said hole (4). C) arranged in such a way that their profile can be seen in a plane along the axial section and so designed that each groove is bounded by oblique lateral sides connected by a rounding at the bottom of the groove (5) and by two adjacent grooves top (6), so that the ratio of the depth (7) of the groove to the division (8) of the grooves is preferably 4:10 so that the diameter of the second, after the diameter of the smaller hole (9) of the first-mentioned fitting part (1) is equal to the diameter of the outer jacket surface ( 10) Expanded Metals furthermore, the metal sleeve (2) is at least 10% longer than the grooves of the hole (4) of the first-named fitting part (1) and is provided with an outer end (11), the ratio of which is the thickness of the wall of the sleeve (2) against the outer diameter thereof is preferably less than 8: 100.

Fitting according to claim 1, characterized in that the part (1) on the outer surface, preferably on the side facing the smooth hole (9), is designed with a profile (13) suitable for engaging with the tool, and preferably with a flange. and / or weldable fittings for tight connection while the other outer surface (14) is cylindrical.

By mandate: Patent Office, d.o.o. For her: Vinko Skubic

22740-PRl-YU / SLO-SK-X / 97

Summary

The invention relates to a fitting (B) suitable for pipe connection with polymer and metal pipes. The fitting (B) has a metal part (1) and a metal sleeve (2). The inner hole (4) has grooves (C). The inner metal sleeve (2) has a thin wall with a flange (11) at one end. The pipe connection is assembled by inserting a part (1) of the fitting onto the connecting tube (15), which was previously inserted into the metal sleeve (2) according to the invention, and then extending from the inside of the sleeve (2) to the tube (15) thereto. the required degrees against the grooves (C) of part (1).