You do not have permission to edit this page, for the following reasons:

This IP address has been blocked from editing Wikipedia.
This does not affect your ability to read Wikipedia pages.
Most people who see this message have done nothing wrong. Some kinds of blocks restrict editing from specific service providers or telecom companies in response to recent abuse or vandalism, and can sometimes affect other users who are unrelated to that abuse. Review the information below for assistance if you do not believe that you have done anything wrong.

The IP address or range 18.206.0.0/16 has been blocked (disabled) by ‪ST47‬ for the following reason(s):

The IP address that you are currently using has been blocked because it is believed to be a web host provider. To prevent abuse, web hosts may be blocked from editing Wikipedia.
You will not be able to edit Wikipedia using a web host provider because it hides your IP address, much like a proxy or VPN.
We recommend that you attempt to use another connection to edit. For example, if you use a proxy or VPN to connect to the internet, turn it off when editing Wikipedia. If you edit using a mobile connection, try using a Wi-Fi connection, and vice versa. If you are using a corporate internet connection, switch to a different Wi-Fi network. If you have a Wikipedia account, please log in.
If you do not have any other way to edit Wikipedia, you will need to request an IP block exemption.

How to appeal if you are confident that your connection does not use a web host's IP address:
If you are confident that you are not using a web host, you may appeal this block by adding the following text on your talk page: ((unblock|reason=Caught by a web host block but this host or IP is not a web host. My IP address is _______. Place any further information here. ~~~~)). You must fill in the blank with your IP address for this block to be investigated. Your IP address can be determined here. Alternatively, if you wish to keep your IP address private you can use the unblock ticket request system. There are several reasons you might be editing using the IP address of a web host (such as if you are using VPN software or a business network); please use this method of appeal only if you think your IP address is in fact not a web host.

Administrators: The IP block exemption user right should only be applied to allow users to edit using web host in exceptional circumstances, and they should usually be directed to the functionaries team via email. If you intend to give the IPBE user right, a CheckUser needs to take a look at the account. This can be requested most easily at SPI Quick Checkuser Requests. Unblocking an IP or IP range with this template is highly discouraged without at least contacting the blocking administrator.

This block will expire on 05:36, 30 September 2026.

Even when blocked, you will usually still be able to edit your user talk page, as well as email administrators and other editors.

For information on how to proceed, please read the FAQ for blocked users and the guideline on block appeals. The guide to appealing blocks may also be helpful.

Other useful links: Blocking policy · Help:I have been blocked
Your IP address is in a range that has been blocked on all Wikimedia Foundation wikis. The block was made by ‪Jon Kolbert‬. The reason given is Open proxy/Webhost: See the help page if you are affected .
- Start of block: 05:37, 21 February 2024
- Expiry of block: 05:37, 21 February 2029
Your current IP address is 18.206.153.34. The blocked range is 18.206.0.0/16. Please include all above details in any queries you make. If you believe you were blocked by mistake, you can find additional information and instructions in the No open proxies global policy. Otherwise, to discuss the block please post a request for review on Meta-Wiki. You could also send an email to the stewards VRT queue at stewards@wikimedia.org including all above details.

You can view and copy the source of this page:

((short description|Type of screw))
((Use dmy dates|date=January 2020))
((Refimprove|date=April 2017))
[[File:Schroef.jpg|thumb|upright=1.2|Two thread-forming self-tapping [[screw]]s with different [[screw head|heads]]. The countersunk head has a [[Pozidriv]] recess.]]
A '''self-tapping screw''' is a [[screw]] that can [[tap and die|tap]] its own hole as it is driven into the material.  More narrowly, self-tapping is used only to describe a specific type of '''thread-cutting''' screw intended to produce a thread in relatively soft material or sheet materials, excluding [[wood screw]]s.  Other specific types of self-tapping screw include '''self-drilling screws''' and '''thread rolling screws'''.

==Mechanism==
[[File:Vis-auto-taraudeuse.jpeg|thumb|left|upright=1.2|Self-tapping screw with [[Flute (cutting tool)|flute]] and type B (blunt) tip]]
Self-tapping screws have a wide range of tip and thread patterns, and are available with almost any possible [[screw head]] design.  Common features are the screw thread covering the whole length of the screw from tip to head and a pronounced thread hard enough for the intended [[wikt:substrate|substrate]], often [[case-hardened]].<ref>((cite web|url=http://www.fastenerdata.co.uk/fasteners/screws/self-tapping-screw/inch-pozi-countersunk-head-self-tapping-screw-b-case-hardened-steel-bs4174.html|title=Fastenerdata|accessdate=10 November 2017))</ref>

For hard substrates such as metal or hard plastics, the self-tapping ability is often created by cutting a gap in the continuity of the thread on the screw, generating a [[Flute (cutting tool)|flute]] and cutting edge similar to those on a [[tap and die|tap]]. Thus, whereas a regular [[screw#Machine screw|machine screw]] cannot tap its own hole in a metal substrate, a self-tapping one can (within reasonable limits of substrate [[hardness]] and depth).

For softer substrates such as wood or soft plastics, the self-tapping ability can come simply from a tip that tapers to a gimlet point (in which no flute is needed). Like the tip of a [[nail (fastener)|nail]] or [[gimlet (tool)|gimlet]], such a point forms the hole by displacement of the surrounding material rather than any [[swarf|chip]]-forming drilling/cutting/evacuating action.

Not all self-tapping screws have a sharp tip.  The ''type B'' tip is blunt and intended for use with a [[pilot hole]], often in sheet materials.  The lack of a sharp tip is helpful for packaging and handling and in some applications may be helpful for reducing the clearance necessary on the reverse of a fastened panel or for making more thread available on a given length screw.<ref>((cite web|url=https://www.orbitalfasteners.co.uk/en/categories/self-tapping-screws|title=Self Tapping Screws|accessdate=9 November 2017))</ref>

== Thread-forming vs. thread-cutting ==
Self-tapping screws can be divided into two classes:<ref >((cite book
  |author=Plastics Design Library
  |title=Handbook of Plastics Joining: A Practical Guide
  |publisher=Cambridge University Press
  |isbn=
  |page=107
))</ref> those that ''displace'' material (especially plastic and thin metal sheets) without removing it, known as "thread-forming" self-tapping screws, and self-tappers with sharp cutting surfaces that ''remove'' the material as they are inserted, termed "thread-cutting" self-tapping screws.

Thread-forming screws may have a non-circular plan view, such as the five-fold symmetry of the [[pentalobular screw thread|pentalobular]] or the three-fold symmetry of Taptite screws, while thread-cutting screws may have one or more flutes machined into their threads, yielding cutting edges.((cn|date=October 2020))

==Self-drilling screws==
[[File:SelfDrillingScrewsx4.png|thumb|upright|A self-drilling screw and three thread-cutting screws]]
Some self-tapping screws such as the Tek screw brand, are also self-drilling, which means that in addition to the thread-forming section there is also a fluted tip much like the tip of a [[center drill]]. These screws combine hole drilling, [[threading (manufacturing)#Threading|threading]] and fastener installation into one driving motion (instead of separate drilling, tapping, and installing motions); they are thus very efficient in a variety of hard-substrate applications, from [[assembly line]]s to [[Roofing material|roofing]].<ref name=drilling >((cite web |url=http://www.firstcallautosupply.com/self-drilling-screws-vs.-self-tapping-screws|title=Self Drilling Screws vs. Self Tapping Screws|accessdate=9 November 2017))</ref><ref name=vs >((cite web |url=https://www.boltsales.com/difference-self-drilling-self-tapping-screws/|title=Self-Drilling vs. Self-Tapping Screws|access-date=9 November 2017))</ref> Some types incorporate a sealing washer, for fastening roofing sheets to purlins.<ref name="Huth2015">((cite book|author=Mark Huth|title=Residential Construction Academy: Basic Principles for Construction|url=https://books.google.com/books?id=vpyaBAAAQBAJ&pg=PA210|date=24 February 2015|publisher=Cengage Learning|isbn=978-1-305-53729-3|pages=210–))</ref>

==Sheet metal screw==
Sheet metal screws (sometimes called "sheet-metal self-tappers", '''P–K''' or '''PK''' screws from the brand name ''Parker Kalon'', the company which pioneered<ref>((cite book |title=Modern Plastics Encyclopedia|volume=33|date=1955|publisher=Breskin & Charlton Publishing Corporation|page=41|location=New York))</ref> the manufacture of, but did not invent, these screws) are a type of screw which can form a thread in thin sheet metal. [[Screw#Pan head|Pan-head]] self-tapping screws are common in metal cases for electrical equipment,<ref>((cite web|url=http://www.electrical.co.nz/categories/pk-self-tapping-screws|title=PK-Self Tapping Screws|last=|first=|date=|website=|url-status=dead|archive-url=https://web.archive.org/web/20170928201146/http://www.electrical.co.nz/categories/pk-self-tapping-screws|archive-date=28 September 2017|accessdate=14 April 2017))</ref> while flatter-headed truss or flat countersunk headed self-tapping screws are found in aviation applications.<ref>((cite web |title=Sheet Metal Screws|url=http://www.aircraftspruce.com/menus/ha/sheetmetalscrews.html|accessdate=14 April 2017))</ref>

==Winged self-tapper==
Winged self-drilling have thin wings wider than the thread formed just behind the self drilling head. These cut a clearance hole in soft materials (such as wood or plastic), but are destroyed by more robust materials (such as metal). Thus, to clamp some material to metal, the clearance drilling, tap drilling, thread tapping, and fixing itself can happen in a single operation from one side, with the materials in their final position.<ref>((cite web|title=How do I Choose the Correct Self-Drilling and Self-Tapping Screws??|url=http://resources.tannerbolt.com/articles/how-do-i-choose-the-correct-self-drilling-and-self-tapping-screws/|accessdate=9 November 2017))</ref>

==Applications==
Self-tapping screws are used in a variety of applications ranging from [[DIY]] carpentry to [[surgery]].

=== Surgical ===
[[Dental implant]]s and [[internal fixation|orthopedic bone screws]] are both examples of self-tapping screws used in surgery. Different thread profiles are used for either denser [[cortical bone]] or the spongy [[cancellous bone]].<ref >((cite book
  |author1=Maurice E. Müller  |author2=Martin Allgöwer
  |title=Manual of INTERNAL FIXATION: Techniques Recommended by the Ao-Asif Group
  |publisher=Springer Science & Business Media
  |page=108
  |isbn=
))</ref>

==See also==
*[[List of screw and bolt types#Fasteners with a tapered shank|Fasteners with a tapered shank]]
*[[Tap and die#Tap|Tap]]

==References==
((Reflist))

==External links==
((Commons category|Self-tapping screws))
* [https://books.google.com/books?id=2yADAAAAMBAJ&dq=popular+science+February+1946&pg=PA151 "Hold Everything", February 1946, ''Popular Science''] bottom of page 151

((DEFAULTSORT:Self-Tapping Screw))
[[Category:Screws]]

Pages transcluded onto the current version of this page (help):

Self-tapping screw (edit)
Template:Ambox (view source) (template editor protected)
Template:Category handler (view source) (protected)
Template:Citation needed (view source) (protected)
Template:Cite book (view source) (protected)
Template:Cite web (view source) (protected)
Template:Cn (view source) (template editor protected)
Template:Commons category (view source) (template editor protected)
Template:DMCA (view source) (template editor protected)
Template:Dated maintenance category (view source) (template editor protected)
Template:Dated maintenance category (articles) (view source) (template editor protected)
Template:Delink (view source) (protected)
Template:FULLROOTPAGENAME (view source) (template editor protected)
Template:Find sources mainspace (view source) (template editor protected)
Template:Fix (view source) (protected)
Template:Fix/category (view source) (protected)
Template:Main other (view source) (protected)
Template:More citations needed (view source) (template editor protected)
Template:Ns has subpages (view source) (protected)
Template:Pagetype (view source) (protected)
Template:Plainlist/styles.css (view source) (protected)
Template:Refimprove (view source) (template editor protected)
Template:Reflist (view source) (protected)
Template:Reflist/styles.css (view source) (protected)
Template:Replace (view source) (protected)
Template:SDcat (view source) (protected)
Template:Short description (view source) (protected)
Template:Short description/lowercasecheck (view source) (protected)
Template:Side box (view source) (template editor protected)
Template:Sister project (view source) (template editor protected)
Template:Use dmy dates (view source) (template editor protected)
Module:Arguments (view source) (protected)
Module:Category handler (view source) (protected)
Module:Category handler/blacklist (view source) (protected)
Module:Category handler/config (view source) (protected)
Module:Category handler/data (view source) (protected)
Module:Category handler/shared (view source) (protected)
Module:Check for unknown parameters (view source) (protected)
Module:Citation/CS1 (view source) (protected)
Module:Citation/CS1/COinS (view source) (protected)
Module:Citation/CS1/Configuration (view source) (protected)
Module:Citation/CS1/Date validation (view source) (protected)
Module:Citation/CS1/Identifiers (view source) (protected)
Module:Citation/CS1/Utilities (view source) (protected)
Module:Citation/CS1/Whitelist (view source) (protected)
Module:Citation/CS1/styles.css (view source) (protected)
Module:Delink (view source) (protected)
Module:Disambiguation/templates (view source) (protected)
Module:Find sources (view source) (template editor protected)
Module:Find sources/config (view source) (template editor protected)
Module:Find sources/links (view source) (template editor protected)
Module:Find sources/templates/Find sources mainspace (view source) (template editor protected)
Module:Message box (view source) (protected)
Module:Message box/ambox.css (view source) (protected)
Module:Message box/configuration (view source) (protected)
Module:Namespace detect/config (view source) (protected)
Module:Namespace detect/data (view source) (protected)
Module:Ns has subpages (view source) (protected)
Module:Pagetype (view source) (protected)
Module:Pagetype/config (view source) (protected)
Module:Pagetype/disambiguation (view source) (protected)
Module:Pagetype/setindex (view source) (protected)
Module:Pagetype/softredirect (view source) (protected)
Module:SDcat (view source) (protected)
Module:Side box (view source) (template editor protected)
Module:Side box/styles.css (view source) (template editor protected)
Module:String (view source) (protected)
Module:Unsubst (view source) (protected)
Module:WikidataIB (view source) (template editor protected)
Module:WikidataIB/nolinks (view source) (template editor protected)
Module:WikidataIB/titleformats (view source) (template editor protected)
Module:Wikitext Parsing (view source) (protected)
Module:Yesno (view source) (protected)

Return to Self-tapping screw.

Retrieved from "https://en.wikipedia.org/wiki/Self-tapping_screw"