Precision polygon

This article needs additional citations for verification. Please help improve this article by adding citations to reliable sources. Unsourced material may be challenged and removed.
Find sources: "Precision polygon" – news · newspapers · books · scholar · JSTOR (March 2023) (Learn how and when to remove this message)

Precision polygons are basic standards for angle measurement, which are used and calibrated by the national standards laboratories in particular. Multifaced polygons are used for calibration of rotary tables and dividing heads.^[1] Any number of faces can be produced.

The minimum size of the reflecting face should be approx. 13 mm x 13 mm. Thus maximum number of faces can be 72, corresponding to an included angle of 5°. Steel polygons are made of high grade steel, hardened and subjected to a suitable heat treatment for stabilisation and the sharp corners are chamfered or rounded off suitably. The reflecting faces are lapped flat to within 0.0001 mm.

According to IS: 6987—1973, these are divided into three types, 1, 2 and 3, with working faces between 5—20, 21—40 and 41—72. The top and supporting surface are lightly lapped and legibly marked. In order for the result of the calibration to be recorded and subsequently applied, the face of the polygon is identified. Each face is identified by engraving on the top surface, the nominal angles with the face and a datum face. The faces may be identified with a series of numbers starting from 1 if nominal angle is not a whole number of degrees. Around 4 holes (plain for type 1 and threaded for types 2 and 3) are provided for clamping purposes. The dimension of polygon between the top and supporting surfaces is 75,150 and 300 mm for types 1, 2 and 3 respectively. The top and supporting surfaces are made flat and parallel to accuracies of 0.0025,0.005 and 0.007 mm, 0.0035,0.005 and 0.04 mm for types 1, 2 and 3 respectively and departure from flatness is permissible only in concave direction. All faces are made square to the bottom supporting surface to an accuracy of 2.5 \xm over the thickness of the polygon. The error in angle between any worke and the datum face and between any two adjacent working faces shall not be more than 10 seconds of arc.^[2]

References

^ de Silva, G. M. S. (16 May 2012). Basic Metrology for ISO 9000 Certification. Taylor & Francis. ISBN 9781136427190. Retrieved 29 March 2023.
^ "IS 6987 (1973): Steel Precision Polygons" (PDF). law.resource.org. Retrieved 29 March 2023.

This standards- or measurement-related article is a stub. You can help Wikipedia by expanding it.

Read other articles:

كأس البوسنة والهرسك 1998–99

يفتقر محتوى هذه المقالة إلى الاستشهاد بمصادر. فضلاً، ساهم في تطوير هذه المقالة من خلال إضافة مصادر موثوق بها. أي معلومات غير موثقة يمكن التشكيك بها وإزالتها. (نوفمبر 2019) كأس البوسنة والهرسك 1998–99 تفاصيل الموسم كأس البوسنة والهرسك النسخة 5 البلد البوسنة والهرسك الم�...

Monde arabe

L'expression de monde arabe (arabe : العالم العربي, al-ʿālam al-ʿarabī ou الوطن العربي al-wațan al-ʿarabī) désigne un ensemble de pays couvrant la péninsule arabique, l'Afrique du Nord et le Proche-Orient, ayant en commun la langue arabe. Bien qu'assez largement utilisé, ce terme ne renvoie pas à une liste définie de pays, et à la différence de la Ligue arabe par exemple, le monde arabe ne constitue pas une entité politique formelle. On peut néanmoi...

2020–21 Campeonato de Portugal

8th season of the Campeonato de Portugal football league Football league seasonCampeonato de PortugalSeason2020–21ChampionsTrofensePromotedTrofenseEstrela da Amadora← 2019–20 2021–22 (L3)2021–22 (CP) → The 2020–21 Campeonato de Portugal was the eighth season of Portuguese football's renovated third-tier league, since the merging of the Segunda Divisão and Terceira Divisão in 2013, and the sixth season under the current Campeonato de Portugal title. A total of 96 teams competed...

Hakkari (province)

Cet article est une ébauche concernant la Turquie. Vous pouvez partager vos connaissances en l’améliorant (comment ?) selon les recommandations des projets correspondants. Pour les articles homonymes, voir Hakkari. Hakkari Administration Pays Turquie Région Anatolie orientale Capitale Hakkari Indicatif téléphonique international +(90) Plaque minéralogique 30 Démographie Population 275 761 hab. (2017[1]) Densité 39 hab./km2 Géographie Superficie 712 100...

Flutter (perangkat lunak)

FlutterTipeKerangka kerja Versi pertamaAlpha (v0.0.6) / Mei 2017; 6 tahun lalu (2017-05)[1]Versi stabil 3.19.0 (15 Februari 2024) GenreKerangka kerja aplikasiLisensilisensi BSD 3-ayat Karakteristik teknisBahasa pemrogramanC++, Dart dan Skia Graphics Engine Informasi pengembangPembuatGooglePengembangGoogle dan komunitasSumber kode Kode sumberPranala Informasi tambahanSitus webflutter.devStack ExchangeEtiqueta Panduan penggunaLaman panduan Sunting di Wikidata • Sunting kota...

Vrije Universiteit Amsterdam

artikel ini perlu dirapikan agar memenuhi standar Wikipedia. Tidak ada alasan yang diberikan. Silakan kembangkan artikel ini semampu Anda. Merapikan artikel dapat dilakukan dengan wikifikasi atau membagi artikel ke paragraf-paragraf. Jika sudah dirapikan, silakan hapus templat ini. (Pelajari cara dan kapan saatnya untuk menghapus pesan templat ini) Vrije Universiteit AmsterdamVrije Universiteit AmsterdamStempel: Maiden in the Garden[1]bahasa Latin: Universitas Libera(Reformata Ams...

Azov campaigns (1695–1696)

Russian military campaigns during the Russo-Turkish War of 1686–1700 Azov campaignsPart of Russo-Turkish War (1686–1700)Capture of Azov by Robert Ker PorterDate1695–1696LocationMoldavia, Wallachia, Armenia, Caucasus, and the DardanellesResult Russian victoryTerritorialchanges Russia captures Azov, Taganrog and a few more fortresses[1][2]Belligerents Tsardom of Russia Don Cossacks Zaporozhian Cossacks Kalmyk cavalry Ottoman EmpireCommanders and leaders Peter the Great Mus...

Krymsk

Town in Krasnodar Krai, Russia Town in Krasnodar Krai, RussiaKrymsk КрымскTown[1] FlagCoat of armsLocation of Krymsk KrymskLocation of KrymskShow map of RussiaKrymskKrymsk (Krasnodar Krai)Show map of Krasnodar KraiCoordinates: 44°55′24″N 37°58′50″E / 44.92333°N 37.98056°E / 44.92333; 37.98056CountryRussiaFederal subjectKrasnodar Krai[1]Founded1858Town status since1958Elevation24 m (79 ft)Population (2010 Census)[...

Harry Warner

Untuk orang lain dengan nama yang sama, lihat Harry Warner (disambiguasi). Harry Warnerc.1918LahirHirsch Moses Wonsal(1881-12-12)12 Desember 1881Krasnosielc, Kongres Polandia, Kekaisaran RusiaMeninggal25 Juli 1958(1958-07-25) (umur 76)Los Angeles, California, Amerika SerikatSebab meninggalOklusi pembuluh darah otak besarMakamTaman Makam Rumah Perdamaian Los Angeles Timur, California, Amerika SerikatPekerjaanEksekutif filmTahun aktif1903–1958Dikenal atasKo-pendiri Warner Bros....

Music history

This article is about the academic field of music history. For an overview of music, see history of music. For the album, see Musical History. This article needs additional citations for verification. Please help improve this article by adding citations to reliable sources. Unsourced material may be challenged and removed.Find sources: Music history – news · newspapers · books · scholar · JSTOR (March 2021) (Learn how and when to remove this message) ...

ヨハネス12世 (ローマ教皇)

ヨハネス12世第130代ローマ教皇教皇就任 955年12月16日教皇離任 964年5月14日先代アガペトゥス2世次代レオ8世個人情報出生 937年スポレート公国（中部イタリア）スポレート死去 964年5月14日教皇領、ローマ原国籍スポレート公国親父アルベリーコ2世（スポレート公）、母アルダその他のヨハネステンプレートを表示ヨハネス12世（Ioannes XII、937年 - 964年5月14日）は、ロ...

Lieutenant colonel (United Kingdom)

Rank in the British Army and Royal Marines Lieutenant colonel Lt Col insignia.Country United KingdomService branch British Army Royal MarinesAbbreviationLt ColNATO rank codeOF-4Next higher rankColonelNext lower rankMajorEquivalent ranksCommander (RN)Wing commander (RAF) Lieutenant colonel (Lt Col), is a rank in the British Army and Royal Marines which is also used in many Commonwealth countries. The rank is superior to major, and subordinate to colonel.[1] The comparabl...

2002 United States gubernatorial elections

2002 United States gubernatorial elections ← 2001 November 5, 2002 2003 → 38 governorships36 states; 2 territories Majority party Minority party Party Republican Democratic Seats before 27 21 Seats after 26 24 Seat change 1 3 Popular vote 30,843,168 27,777,088 Percentage 49.37% 44.47% Seats up 23 11 Seats won 22 14 Third party Fourth party Party Independent Independence Seats before 1 1 Seats after 0 0 Seat ...

Brotterode

Cet article est une ébauche concernant l’Allemagne. Vous pouvez partager vos connaissances en l’améliorant (comment ?) selon les recommandations des projets correspondants. Cet article court présente un sujet plus développé dans : Brotterode-Trusetal. Brotterode Héraldique Administration Pays Allemagne Land Thuringe Commune(Gemeinde) Brotterode-Trusetal Code postal 98596 Démographie Population 3 052 hab. (2012) Densité 128 hab./km2 Géographie Coord...

Así en el barrio como en el cielo

Mexican telenovela Así en el barrio como en el cieloGenreTelenovelaCreated by Guillermo López Leticia López Margali Directed by Fabián Corres Juan Patrón Fox Starring Juan Manuel Bernal Verónica Merchant Patricia Bernal José Alonso Marcela Guirado Luciano Zacharsky Opening themeNadie como tú by Yahir[1]Country of originMexicoOriginal languageSpanishNo. of episodes120ProductionExecutive producerFides VelascoProducerJacky CastroRunning time42-60 minutesProduction companyTV Aztec...

1998 Malpa landslide

Fatal landslide in Uttar Pradesh, India 1998 Malpa landslideDate18 August 1998LocationMalpa village Pithoragarh district, Uttar Pradesh, IndiaTypelandslideDeaths221Non-fatal injuriesunknown The Malpa landslide was one of the worst landslides in India. On 18 August 1998 at 3.00 a.m., massive landslide wiped away the entire village of Malpa in the Pithoragarh district of Uttarakhand, then in Uttar Pradesh in Kali Valley of Higher Kumaon division of the Himalayas. The rockfall started on 16 Augu...

2015 Provence-Alpes-Côte d'Azur regional election

You can help expand this article with text translated from the corresponding article in French. (December 2015) Click [show] for important translation instructions. View a machine-translated version of the French article. Machine translation, like DeepL or Google Translate, is a useful starting point for translations, but translators must revise errors as necessary and confirm that the translation is accurate, rather than simply copy-pasting machine-translated text into the English Wikip...

Jordan Jegat

Jordan JegatNazionalità Francia Altezza176 cm Peso59 kg Ciclismo SpecialitàStrada Squadra TotalEnergies CarrieraGiovanili 2017OC Locminé2018-2019Team Fybolia-Locminé Auto2020-2021CIC U Nantes Atlantique Squadre di club 2022-2023CIC U Nantes Atlantique2024- TotalEnergies Statistiche aggiornate al 28 aprile 2024 Modifica dati su Wikidata · Manuale Questa voce sull'argomento ciclisti francesi è solo un abbozzo. Contribuisci a migliorarla secondo le convenzioni ...

2022 United States Senate election in Alabama

For related races, see 2022 United States Senate elections. Not to be confused with 2022 Alabama Senate election. 2022 United States Senate election in Alabama ← 2016 November 8, 2022 2028 → Turnout38.50% Nominee Katie Britt Will Boyd Party Republican Democratic Popular vote 942,154 436,746 Percentage 66.62% 30.88% County results Congressional district results Precinct resultsBritt: 40–50% 50–60...

Addie McPhail

Questa voce sull'argomento attori statunitensi è solo un abbozzo. Contribuisci a migliorarla secondo le convenzioni di Wikipedia. Segui i suggerimenti del progetto di riferimento. Addie McPhail nel 1927 Addie Oakley Dukes (White Plains, 15 luglio 1905 – Canoga Park, 14 aprile 2003) è stata un'attrice statunitense, meglio nota con il cognome del primo marito, McPhail. Dal primo marito, il pianista e compositore Lindsay McPhail, ebbe una figlia, Marilyn. Nel 1932 sposò in seconde noz...