V\u00fdb\u011br spojovac\u00edho materi\u00e1lu nen\u00ed jen ot\u00e1zka rozm\u011bru. Rozhoduje typ hlavy, z\u00e1vit, t\u0159\u00edda pevnosti, prost\u0159ed\u00ed i to, s jak\u00fdm protikusem \u0161roub kombinujete. Tento rozcestn\u00edk v\u00e1s provede v\u00fdb\u011brem od z\u00e1kladn\u00ed geometrie po utahovac\u00ed moment a kompatibilitu materi\u00e1l\u016f. Detailn\u00ed postupy najdete v odkazovan\u00fdch \u010dl\u00e1nc\u00edch.<\/p>\n
Ne\u017e za\u010dnete vyb\u00edrat konkr\u00e9tn\u00ed zbo\u017e\u00ed, vyplat\u00ed se ujasnit si t\u0159i v\u011bci: jak\u00e9 zat\u00ed\u017een\u00ed spoj p\u0159en\u00e1\u0161\u00ed (tah, st\u0159ih, kombinace), v jak\u00e9m prost\u0159ed\u00ed bude pracovat (interi\u00e9r, exteri\u00e9r, chemie, mo\u0159e) a jak\u00e9 n\u00e1\u0159ad\u00ed budete m\u00edt p\u0159i mont\u00e1\u017ei k dispozici. Tyto t\u0159i ot\u00e1zky p\u0159edur\u010d\u00ed materi\u00e1l, t\u0159\u00eddu pevnosti i typ hlavy. Teprve potom m\u00e1 smysl \u0159e\u0161it p\u0159esn\u00e9 rozm\u011bry. N\u00e1sleduj\u00edc\u00ed sekce odpov\u00eddaj\u00ed krok za krokem na ot\u00e1zky, kter\u00e9 p\u0159i v\u00fdb\u011bru spojovac\u00edho materi\u00e1lu \u0159e\u0161\u00ed technik i n\u00e1kup\u010d\u00ed nej\u010dast\u011bji.<\/p>\n
Z\u00e1kladem je spr\u00e1vn\u00e9 odm\u011b\u0159en\u00ed pr\u016fm\u011bru, stoup\u00e1n\u00ed z\u00e1vitu a d\u00e9lky. U metrick\u00e9ho z\u00e1vitu se uv\u00e1d\u00ed jmenovit\u00fd pr\u016fm\u011br (M6, M8, M10…) a stoup\u00e1n\u00ed. D\u00e9lka se m\u011b\u0159\u00ed bez hlavy u \u0161estihrann\u00fdch \u0161roub\u016f, u z\u00e1pustn\u00fdch hlav v\u010detn\u011b hlavy. Pozor na z\u00e1m\u011bnu metrick\u00e9ho a palcov\u00e9ho (UNC\/UNF) z\u00e1vitu – vizu\u00e1ln\u011b podobn\u00e9 \u0161rouby s jin\u00fdm stoup\u00e1n\u00edm do sebe nepasuj\u00ed a hroz\u00ed po\u0161kozen\u00ed z\u00e1vitu. Jmenovit\u00fd pr\u016fm\u011br m\u011b\u0159te posuvn\u00fdm m\u011b\u0159\u00edtkem p\u0159es vrcholy z\u00e1vitu, stoup\u00e1n\u00ed nejl\u00e9pe z\u00e1vitov\u00fdm h\u0159ebenem; u b\u011b\u017en\u00fdch velikost\u00ed m\u00e1 metrick\u00fd z\u00e1vit standardn\u00ed (hrub\u00e9) stoup\u00e1n\u00ed, ale existuj\u00ed i jemn\u00e9 varianty se sn\u00ed\u017een\u00fdm stoup\u00e1n\u00edm pro p\u0159esn\u00e9 spoje.<\/p>\n
Typ hlavy ur\u010duje n\u00e1stroj a zp\u016fsob zat\u00ed\u017een\u00ed. \u0160estihrann\u00e1 hlava (DIN 933\/931) je univerz\u00e1ln\u00ed pro kl\u00ed\u010d, v\u00e1lcov\u00e1 hlava s vnit\u0159n\u00edm \u0161estihranem (DIN 912 \/ ISO 4762) se hod\u00ed do zahlouben\u00ed, z\u00e1pustn\u00e1 hlava (DIN 7991) zajist\u00ed l\u00edcov\u00e1n\u00ed s povrchem. Pro plech vol\u00edte samo\u0159ezn\u00e9 nebo z\u00e1vito\u0159ezn\u00e9 \u0161rouby.<\/p>\n
P\u0159\u00edklady z nab\u00eddky: imbusov\u00fd \u0161roub DIN 912 A2<\/a> nebo z\u00e1pustn\u00fd \u0161roub DIN 7991 A2<\/a>.<\/p>\n K \u0161roubu je pot\u0159eba zvolit matici se shodn\u00fdm z\u00e1vitem, materi\u00e1lem a odpov\u00eddaj\u00edc\u00ed pevnostn\u00ed t\u0159\u00eddou. Standardn\u00ed \u0161estihrann\u00e1 matice (DIN 934) posta\u010d\u00ed pro b\u011b\u017en\u00e9 spoje, samojistn\u00e1 matice s plastov\u00fdm krou\u017ekem (DIN 985) zabra\u0148uje povolen\u00ed vibracemi, n\u00edzk\u00e1 matice (DIN 439) se uplatn\u00ed jako pojistn\u00e1.<\/p>\n Nap\u0159. samojistn\u00e1 matice DIN 985 A2<\/a>.<\/p>\n Podlo\u017eka rozkl\u00e1d\u00e1 tlak pod hlavou nebo matic\u00ed a chr\u00e1n\u00ed povrch. Ploch\u00e1 podlo\u017eka (DIN 125) je univerz\u00e1ln\u00ed, velkoplo\u0161n\u00e1 (DIN 9021) se hod\u00ed na m\u011bkk\u00e9 materi\u00e1ly a do prodlou\u017een\u00fdch otvor\u016f, pru\u017en\u00e1 p\u00e9rov\u00e1 podlo\u017eka (DIN 127) pom\u00e1h\u00e1 proti povolen\u00ed u m\u00e9n\u011b nam\u00e1han\u00fdch spoj\u016f.<\/p>\n Nap\u0159. ploch\u00e1 podlo\u017eka DIN 125 A2<\/a>.<\/p>\n Pevnost spoje mus\u00ed odpov\u00eddat zat\u00ed\u017een\u00ed. Pro b\u011b\u017en\u00e9 konstrukce sta\u010d\u00ed 8.8, pro vysoce nam\u00e1han\u00e9 spoje s\u00e1hn\u011bte po 10.9 nebo 12.9. U nerezu rozli\u0161ujte A2-70 a A4-80. V\u017edy kombinujte \u0161roub s matic\u00ed odpov\u00eddaj\u00edc\u00ed nebo vy\u0161\u0161\u00ed t\u0159\u00eddy.<\/p>\n P\u0159edepsan\u00fd utahovac\u00ed moment zajist\u00ed spr\u00e1vn\u00e9 p\u0159edp\u011bt\u00ed spoje – p\u0159\u00edli\u0161 n\u00edzk\u00fd moment vede k povolen\u00ed, p\u0159\u00edli\u0161 vysok\u00fd k p\u0159etr\u017een\u00ed nebo po\u0161kozen\u00ed z\u00e1vitu. Moment z\u00e1vis\u00ed na pr\u016fm\u011bru, t\u0159\u00edd\u011b pevnosti, materi\u00e1lu a t\u0159en\u00ed (maz\u00e1n\u00ed, povrchov\u00e1 \u00faprava). U nerezu je riziko zad\u0159en\u00ed z\u00e1vitu (galling), proto se doporu\u010duje mazivo a citliv\u00e9 utahov\u00e1n\u00ed.<\/p>\n Pro opakovateln\u00fd v\u00fdsledek pou\u017e\u00edvejte momentov\u00fd kl\u00ed\u010d a hodnoty \u010dt\u011bte z tabulky pro dan\u00fd pr\u016fm\u011br, t\u0159\u00eddu a stav povrchu. M\u011bjte na pam\u011bti, \u017ee mazan\u00fd spoj dos\u00e1hne stejn\u00e9ho p\u0159edp\u011bt\u00ed p\u0159i ni\u017e\u0161\u00edm momentu ne\u017e such\u00fd – tabulkov\u00e9 hodnoty proto v\u017edy berte ve vazb\u011b na p\u0159edpokl\u00e1dan\u00e9 t\u0159en\u00ed. U nerezov\u00fdch spoj\u016f utahujte plynule, bez r\u00e1z\u016f, a p\u0159i mont\u00e1\u017ei v\u00edce kus\u016f nasa\u010fte mazivo s MoS2 nebo pastu proti zad\u0159en\u00ed; jednou zad\u0159en\u00fd nerezov\u00fd z\u00e1vit se zpravidla ned\u00e1 zachr\u00e1nit a spoj se mus\u00ed vyvrtat.<\/p>\n Spojov\u00e1n\u00ed r\u016fzn\u00fdch kov\u016f m\u016f\u017ee vyvolat galvanickou (elektrochemickou) korozi. Nerezov\u00fd \u0161roub v hlin\u00edkov\u00e9 konstrukci nebo styk pozinkovan\u00e9ho a nerezov\u00e9ho d\u00edlu vy\u017eaduje pozornost – pom\u00e1h\u00e1 odd\u011blen\u00ed podlo\u017ekou, vhodn\u00e1 volba materi\u00e1lu nebo izolace. V mo\u0159sk\u00e9m a chemick\u00e9m prost\u0159ed\u00ed volte konzistentn\u011b A4.<\/p>\n Pro hlub\u0161\u00ed porozum\u011bn\u00ed norm\u00e1m a materi\u00e1l\u016fm nav\u0161tivte rozcestn\u00edk Normy a materi\u00e1ly<\/a>. P\u0159i rozhodov\u00e1n\u00ed mezi konkr\u00e9tn\u00edmi variantami pomohou Produktov\u00e1 srovn\u00e1n\u00ed<\/a>. Ve\u0161ker\u00fd spojovac\u00ed materi\u00e1l m\u00e1me skladem v Praze i Ostrav\u011b s expedic\u00ed do 48 hodin.<\/p>\n","protected":false},"excerpt":{"rendered":" N\u00e1vod, jak vybrat \u0161roub, matici i podlo\u017eku: rozm\u011bry, z\u00e1vit, t\u0159\u00edda pevnosti, utahovac\u00ed momenty a kombinace materi\u00e1l\u016f. Pro techniky a \u00fadr\u017eb\u00e1\u0159e.<\/p>\n","protected":false},"author":1,"featured_media":0,"parent":0,"menu_order":0,"comment_status":"closed","ping_status":"closed","template":"","meta":{"_matai_meta_desc":"N\u00e1vod, jak vybrat \u0161roub, matici i podlo\u017eku: rozm\u011bry, z\u00e1vit, t\u0159\u00edda pevnosti, utahovac\u00ed momenty a kombinace materi\u00e1l\u016f. Pro techniky a \u00fadr\u017eb\u00e1\u0159e.","_matai_faq":"","_matai_schema_type":"Article","footnotes":""},"class_list":["post-8","page","type-page","status-publish","hentry"],"_links":{"self":[{"href":"https:\/\/www.matai.cz\/blog\/wp-json\/wp\/v2\/pages\/8","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.matai.cz\/blog\/wp-json\/wp\/v2\/pages"}],"about":[{"href":"https:\/\/www.matai.cz\/blog\/wp-json\/wp\/v2\/types\/page"}],"author":[{"embeddable":true,"href":"https:\/\/www.matai.cz\/blog\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/www.matai.cz\/blog\/wp-json\/wp\/v2\/comments?post=8"}],"version-history":[{"count":1,"href":"https:\/\/www.matai.cz\/blog\/wp-json\/wp\/v2\/pages\/8\/revisions"}],"predecessor-version":[{"id":400,"href":"https:\/\/www.matai.cz\/blog\/wp-json\/wp\/v2\/pages\/8\/revisions\/400"}],"wp:attachment":[{"href":"https:\/\/www.matai.cz\/blog\/wp-json\/wp\/v2\/media?parent=8"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}V\u00fdb\u011br matice<\/h2>\n
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V\u00fdb\u011br podlo\u017eky<\/h2>\n
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T\u0159\u00edda pevnosti a \u00fanosnost spoje<\/h2>\n
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Utahovac\u00ed momenty<\/h2>\n
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Kombinace materi\u00e1l\u016f a galvanick\u00e1 koroze<\/h2>\n
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Kam d\u00e1l<\/h2>\n