{"id":1244,"date":"2021-10-10T08:31:16","date_gmt":"2021-10-10T08:31:16","guid":{"rendered":"https:\/\/rolexiron.com\/?page_id=1244"},"modified":"2021-10-10T08:31:17","modified_gmt":"2021-10-10T08:31:17","slug":"manufacture-of-silver-impregnated-contacts-sig-certified-approved-by-railway-rdso","status":"publish","type":"page","link":"https:\/\/rolexiron.com\/index.php\/manufacture-of-silver-impregnated-contacts-sig-certified-approved-by-railway-rdso\/","title":{"rendered":"Manufacture of Silver Impregnated Contacts (SIG) Certified &#038; Approved by Railway RDSO"},"content":{"rendered":"\n<p>Manufacture of Silver Impregnated Contacts (SIG) Certified &amp; Approved by Railway RDSO<\/p>\n\n\n\n<p>Manufacture of Silver Impregnated Contact (SIG)<br>Manufacture of Silver-Impregnated Contacts (SIG)<br>Manufacture of Silver Impregnated Graphite Contact<br>Manufacture of Silver-Impregnated Graphite Contacts<br>Manufacture of Silver Impregnated Graphite Relay Contact<br>Manufacture of Silver-Impregnated Graphite Relay Contacts<br>Manufacture of SIG Contact<br>Manufacture of SIG Contacts<br>Manufacture of S.I.G Contact<br>Manufacture of S.I.G Contacts<br>Manufacture of RDSO Approved Silver Impregnated Contact (SIG)<br>Manufacture of RDSO Certified Silver-Impregnated Contacts (SIG)<br>Manufacture of RDSO Approved Silver Impregnated Graphite Contact<br>Manufacture of RDSO Certified Silver-Impregnated Graphite Contacts<br>Manufacture of RDSO Approved Silver Impregnated Graphite Relay Contact<br>Manufacture of RDSO Certified Silver-Impregnated Graphite Relay Contacts<br>Manufacture of RDSO Approved SIG Contact<br>Manufacture of RDSO Certified SIG Contacts<br>Manufacture of RDSO Approved S.I.G Contact<br>Manufacture of RDSO Certified S.I.G Contacts<br>Manufacture of Silver Impregnated Contact (SIG) Approved by Indian Railway<br>Manufacture of Silver-Impregnated Contacts (SIG) Certified by Indian Railways<br>Manufacture of Silver Impregnated Graphite Contact Approved by Indian Railway<br>Manufacture of Silver-Impregnated Graphite Contacts Certified by Indian Railways<br>Manufacture of Silver Impregnated Graphite Relay Contact Approved by Indian Railway<br>Manufacture of Silver-Impregnated Graphite Relay Contacts Certified by Indian Railways<br>Manufacture of SIG Contact Approved by Indian Railway<br>Manufacture of SIG Contacts Certified by Indian Railways<br>Manufacture of S.I.G Contact Approved by Indian Railway<br>Manufacture of S.I.G Contacts Certified by Indian Railways<\/p>\n\n\n\n<p>Silver Impregnated Graphite (SIG) contacts are used in high safety applications of railway signaling, traffic signaling, and numerous other applications due to high silver content that eliminates the risk of welding in the presence of graphite. High contact resistance (&gt;200mO) was observed in the SIG contacts in a railway signaling operation after a few thousand operations of the relay. The high contact resistance was discovered to be a result of loose dust\/foreign particles residing between the two contacts. Silver had been preferentially removed from the contacting surfaces during switching operations by an abrading effect of the dust\/foreign particles, leaving only graphite on the contact area. Wear was accentuated by the presence of porosity and low hardness of the contacts, leading to improper interaction between the mating surfaces.<\/p>\n\n\n\n<p>Silver Impregnated Graphite relay contacts combine the best properties of silver (electrical\/thermal conductivity) and graphite (refractory nature) into a composite material. Distinctive features of the SIG material include its hard fusing characteristic, better conduction of heat and electricity, and easy brazing. Graphite carbon has high heat of vaporization and appreciably low material transfer in the localized high temperature spots developed during mating of contacts. Additionally, due to a high percentage of silver, the desired electrical properties are retained with practically no risk of welding. This combination of properties makes these contacts suitable for high safety applications such as railway signaling, traffic signaling, and numerous other applications.<\/p>\n\n\n\n<p>Silver Impregnated Graphite contacts are generally tested for dimensions, crushing strength, silver content, hardness, ash content, distribution of silver in the graphite matrix, contact resistance, X-ray mapping of silver, microstructure, life test, surface finish, and bulk density. The quality assurance of electrical contacts is often treated as an evaluation of &#8220;components in great quantity&#8221; and tested with statistical methods. This maybe the reasonable for the registration of fabrication defects, but consideration is also required for systematic failures related to specific materials, environmental influences during processing, application, and so forth. Failures caused by environmental influence occur late in the lifetime of the contact or component and may not be detected by early evaluations. Additionally, contamination on the surface of contacts and have deleterious effect on the contact and switching properties and may, in extreme cases, lead to early failure of devices.<\/p>\n\n\n\n<p>BRIEF OF OUR PRODUCT:<br>Our product is SILVER IMPREGNATED GRAPHITE CONTACTS (SIG CONTACTS), which are extensively used as contact material for various Signaling Relay applications.<\/p>\n\n\n\n<p>SIG CONTACTS are Non-Weld able Graphite contacts which have 55-60 % of Silver impregnated in their matrix due to which these have a very-very low Contact Resistance of less than 20 m-ohms. These are Electroplated with Silver (one side) to make them weld able &amp; can be attached to various relay. SIG CONTACTS are made of various shapes &amp; size to cater the demands of various Relay .<\/p>\n\n\n\n<p>CHARACTERISTICS OF OUR PRODUCT<br>Our company specializes in manufacture of SILVER IMPREGNATED GRAPHITE CONTACTS.<\/p>\n\n\n\n<p>We are involve in making customize SILVER IMPREGNATED GRAPHITE CONTACTS for Indian railways&amp; other relay manufactures, which are intern used for various Shelf type line &amp; track relays confirming to IRS: S53 &amp; BS: 1659 For signaling purposes. Silver impregnated relay contacts combine the best properties of conducting silver &amp; refractory graphite metal. These contacts are widely used in railway signaling relay. The distinctive feature of the silver impregnated carbon material is its hard fusing characteristics, better conduction of heat &amp; electricity, easy brazing etc.<\/p>\n\n\n\n<p>Silver impregnated graphite (SIG) contacts are used in high safety applications of railway signaling, traffic signaling, and numerous other applications due to high silver content that eliminates the risk of welding in the presence of graphite. High contact resistance (&gt;200 mO) was observed in SIG contacts in a railway signaling operation after a few thousand operations of the relay. The high contact resistance was discovered to be a result of loose dust\/foreign particles residing between the two contacts. Silver had been preferentially removed from the contacting surfaces during switching operations by an abrading effect of the dust\/foreign particles, leaving only graphite on the contact area. Wear was accentuated by the presence of porosity and low hardness of the contacts, leading to improper interaction between the mating surfaces.<\/p>\n\n\n\n<p>Silver Impregnated Graphite contacts used in metal to carbon relays combine the best properties of conducting silver<br>and refractory graphite carbon. The distinctive features of<br>the silver-carbon material are its hard fusing characteristics,<br>better conduction of heat and electricity, easy brazing etc.<br>The electro \u2013 graphite for these SIG contacts is manufactured using the Press-Sinter-Infiltrate (PSI) process of powder metallurgy, which provides the highest density material.<br>Silver impregnation is done to achieve high level of electrical conductivity. The SIG contacts are made from graphite<br>blocks, by several cutting, machining &amp; shaping processes.<br>Impregnation is carried out by soaking the graphite pieces in<br>silver nitrate solution under high vacuum for adequate time<br>and then washing the pieces gently by triple distilled water<br>to remove any sticking silver nitrate from the surface. Then<br>the silver nitrate is reduced into silver through the process of<br>\u2018firing\u2019 and then electroplated on backside for soldering. Finally, three-stage cleaning of SIG contacts is done to remove<br>any water &#8211; soluble impurities remaining after electroplating.<br>The final product, as shown in figure 1, shall contain 55% to<br>60% by weight of silver (without considering the silver plated<br>portion) and the distribution of silver throughout the volume<br>of contact, as seen in micrographs, shall be uniform and free<br>from defects viz. seams, threads, or silver globules [1]. The<br>specific resistance of impregnated graphite shall not exceed<br>2\u00d710-4 ohms-cm, while the compressive strength of contact<br>shall not be less than 700 kg\/cm2 [1]. The hardness of contact shall not be less than 22 VPN. The water-soluble impurities in the finished contacts shall not exceed 0.25% [1].<\/p>\n\n\n\n<p>Inspection &amp; Approval Certificates : C\/W Certificate (Calibration Works Certificate) EN 10204 3.1 \/ DIN 50049 3.1 \/ ISO 10474 3.1 Mill Test Certificate,<br>NACE HIC TM-0284 \/ NACE MR-0103 \/ NACE MR-0175 \/ ISO 15166, CE Marked, European Pressure Equipment Directive PED-2014\/68\/EU, AD-2000-WO,<br>ASME Boiler &amp; Pressure Vessel Code Section-II Part A Edition 2019, API 6A (American Petroleum Institute), with 3.2 Certificate duly Certified &amp;<br>Approved by IBR (Indian Boiler Regulations), LR Class (Lloyd\u2019s Register), GL (Germanischer Lloyd), BV (Bureau Veritas), DNV (Det Norske Veritas),<br>ABS Class (American Bureau of Shipping), SGS, TUV, RINA, IR Class (Indian Register of Shipping), NORSOK Approved Standard M-630, M-650 Rev.3<\/p>\n\n\n\n<p>If you have any requirement of above items, please feel free to contact us<\/p>\n\n\n\n<p>Regards,<\/p>\n\n\n\n<p><strong>CONTACT PERSON :<\/strong><\/p>\n\n\n\n<p><strong>MUKESH SHAH<br>Director<br>Mobile No. 0091 \u2013 9820292499<br>Email \u2013 marketing@rolexmetals.com<\/strong><\/p>\n\n\n\n<p><strong>ROLEX METAL DISTRIBUTORS<br>57-A Khatargalli<br>Thakurdwar<br>Mumbai \u2013 400 002 India<br>0091-22-23858802<br>0091-22-23823963<br>0091-22-23898724<br>marketing@rolexmetals.com<br>www.rolexmetals.com<\/strong><\/p>\n\n\n\n<p>CHAIRMAN \u2013 chairman@rolexmetals.com<br>MANAGING DIRECTOR \u2013 managingdirector@rolexmetals.com<br>TECHNICAL DIRECTOR \u2013 technicaldirector@rolexmetals.com<br>SALES DIRECTOR \u2013 salesdirector@rolexmetals.com<br>COMMERCIAL DIRECTOR \u2013 commercialdirector@rolexmetals.com<br>COMMERCIAL MANAGER \u2013 commercial@rolexmetals.com<br>GENERAL MANAGER \u2013 generalmanager@rolexmetals.com<br>SALES MANAGER \u2013 salesmanager@rolexmetals.com<br>PURCHASE MANAGER \u2013 purchasemanager@rolexmetals.com<br>TECHNICAL MANAGER \u2013 technical@rolexmetals.com<br>WORKS MANAGER \u2013 worksmanager@rolexmetals.com<br>STORES MANAGER \u2013 stores@rolexmetals.com<br>WAREHOUSE MANAGER \u2013 warehouse@rolexmetals.com<br>SALES DOMESTIC \u2013 salesdomestic@rolexmetals.com<br>SALES INTERNATIONAL \u2013 salesinternational@rolexmetals.com<br>SALES GENERAL \u2013 sales@rolexmetals.com<br>PURCHASE GENERAL \u2013 purchase@rolexmetals.com<br>FINANCE MANAGER \u2013 finance@rolexmetals.com<br>ACCOUNTS MANAGER \u2013 accounts@rolexmetals.com<br>GENERAL INFORMATION \u2013 info@rolexmetals.com<br>EXPORT MANAGER \u2013 export@rolexmetals.com<br>IMPORT MANAGER \u2013 import@rolexmetals.com<br>AIR EXPORT \u2013 airexport@rolexmetals.com<br>SEA EXPORT \u2013 seaexport@rolexmetals.com<br>CUSTOMS \u2013 customs@rolexmetals.com<br>AIR FREIGHT \u2013 airfreight@rolexmetals.com<br>SEA FREIGHT \u2013 seafreight@rolexmetals.com<br>DESPATCH \u2013 despatch@rolexmetals.com<br>INSPECTION \u2013 inspection@rolexmetals.com<br>LOGISTICS \u2013 logistics@rolexmetals.com<br>TRANSPORT \u2013 transport@rolexmetals.com<br>KALAMBOLI WAREHOUSE \u2013 kalamboli@rolexmetals.com<br>TALOJA WAREHOUSE \u2013 taloja@rolexmetals.com<br>KHOPOLI WAREHOUSE \u2013 khopoli@rolexmetals.com<br>NHAVA SHEVA WAREHOUSE \u2013 nhavasheva@rolexmetals.com<br>KANDLA WAREHOUSE \u2013 kandla@rolexmetals.com<br>MUMBAI WAREHOUSE \u2013 mumbai@rolexmetals.com<br>STOCKYARD \u2013 stockyard@rolexmetals.com<br>SERVICE \u2013 service@rolexmetals.com<br>SUPPORT \u2013 support@rolexmetals.com<br>RECRUITMENT \u2013 career@rolexmetals.com<br>WEBMASTER \u2013 webmaster@rolexmetals.com<br>CUSTOMER CARE \u2013 customercare@rolexmetals.com<\/p>\n","protected":false},"excerpt":{"rendered":"<p>Manufacture of Silver Impregnated Contacts (SIG) Certified &amp; Approved by Railway RDSO Manufacture of Silver Impregnated Contact (SIG)Manufacture of Silver-Impregnated Contacts (SIG)Manufacture of Silver Impregnated Graphite ContactManufacture of Silver-Impregnated Graphite ContactsManufacture of Silver Impregnated Graphite Relay ContactManufacture of Silver-Impregnated Graphite Relay ContactsManufacture of SIG ContactManufacture of SIG ContactsManufacture of S.I.G ContactManufacture of S.I.G ContactsManufacture of [&hellip;]<\/p>\n","protected":false},"author":1,"featured_media":0,"parent":0,"menu_order":0,"comment_status":"closed","ping_status":"closed","template":"","meta":{"footnotes":""},"class_list":["post-1244","page","type-page","status-publish","hentry"],"_links":{"self":[{"href":"https:\/\/rolexiron.com\/index.php\/wp-json\/wp\/v2\/pages\/1244","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/rolexiron.com\/index.php\/wp-json\/wp\/v2\/pages"}],"about":[{"href":"https:\/\/rolexiron.com\/index.php\/wp-json\/wp\/v2\/types\/page"}],"author":[{"embeddable":true,"href":"https:\/\/rolexiron.com\/index.php\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/rolexiron.com\/index.php\/wp-json\/wp\/v2\/comments?post=1244"}],"version-history":[{"count":1,"href":"https:\/\/rolexiron.com\/index.php\/wp-json\/wp\/v2\/pages\/1244\/revisions"}],"predecessor-version":[{"id":1245,"href":"https:\/\/rolexiron.com\/index.php\/wp-json\/wp\/v2\/pages\/1244\/revisions\/1245"}],"wp:attachment":[{"href":"https:\/\/rolexiron.com\/index.php\/wp-json\/wp\/v2\/media?parent=1244"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}