Amachinescrew' sstrengthmeansitoftenisusedtojoinmachineparts, andhoosingtherightcrew
involvesmanyfactors.Thelengthandthicknessofthemachinescrewisimportant, becausethescrew
hastobelongenoughtojointhepiecesandthickenoughtokeepthemtogether.Thistypeofscrewcan
bemadefrommanyразличниматериали, включително иеландсилон, andisalsowilldeterminetheschew' s
durability.Therearemanyheadshapes, suchasPhillipsheadandslottedhead, thatwilldeterminewhat
typeofdrillorscrewdrivercanbeused.Therealsoarepan, hexandflatheads.
Whenchoosingamachinescrew, youshouldlookatthepiecesyouhavetojointogether.Youshouldthen
chooseascrewthatislongenoughtogothroughthepiecesandthickenoughtokeepthemtogether.
Thicknesscanbedeterminedbythematerialofthescrew, thematerialofthepiecesandhowmuchstress
thepieceswillencounterduringuse.Forlength, thescrewshouldbeslightlylongerthantheconjoinedpieces
toensureanutcanbeplacedontheothersideofthescrewtoadherethem.
Therearemanymaterialsusedtomakeamachinescrew.Mostmaterialsaremadefrommetal, suchassteel
andbrass, butnylonandplasticalsoareused.Eachmaterialwillhaveadifferentstrength, rustresistance,
magnetismresistanceanddurability.Youshouldchooseascrewbasedonthesepropertiesandwhatyour
projectspecificallyneeds.
Tofastenamachinescrew, oneusesadrillorscrewdriverthathasacertainhead.Theheadonthescrewdriver
ordrillmustmatchtheheadonthescrew, orthetwowillbeincompatible.Choosingbetweenthedifferent
screwheadsnormallycomesdowntothetoolyouhaveandwhetheryouwantascrewthathasbetter
въртящ момент-Phillipshead-ormoredrivingforce-slottedhead.
Alongwiththefittingatthetopofthehead, therearethreedifferentheadtypes.Aflatheadisacompletelyflat
отгоре, andthisnormallyisbestforprojectsinwhichthescrewshouldbeflushagainstasurface.Panheadsstick
upabitandtendtobeeasiertoremove, becausetheybumpupslightlyfromthesurface.Hexheadsoftencan
takemorestressthantheothers, andtheytendtobebetterforheavy-dutyprojects.
Pringmetalможе да произвежда повечето видовемашинни винтовес високо качество също винтовете по поръчка могат да бъдат произведени по специфични стандарти.
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