Centrifuge Production Facilities

7th of Tir Industries (Seventh of Tir, Hafte Tir or Haftom e Tir Industries)

Seventh of Tir Industries, located near Esfahan, is under the Defense Industries Organization and a subsidiary of the Ammunition and Metallurgy Industries Group (AMIG).  It is mainly involved in manufacturing rockets and missiles.  United Nations Security Council Resolution 1737 (2006) states that 7th of Tir is “widely recognized as being directly involved in the nuclear program.”

The company takes its name from an important date on the Iranian calendar – the 7th of Tir – on which a bomb exploded at the headquarters of Iran’s Islamic Republic Party on June 28, 1981, killing more than seventy officials.  A number of Iranian buildings or places now bear the name.

Prior to the 2003 suspension of Iran’s sensitive nuclear programs, 7th of Tir had responsibility for manufacturing several critical P1 centrifuge components under a contract with the centrifuge program.  This facility had some of the most sophisticated machining capabilities in Iran, achieved through overseas procurements of sophisticated machine tools and technology.

Whether it continues to make centrifuge components is uncertain, based on public information and reports by the International Atomic Energy Agency (IAEA).  Iran is not required under its comprehensive safeguards agreement to declare to the IAEA where it makes centrifuge components and thus there is little official information about centrifuge manufacturing in Iran.  However, 7th of Tir’s capabilities would have been a powerful motivation for the centrifuge program to continue contracting with this defense company to make sensitive centrifuge components.  It may therefore be making centrifuge components today.

Public information about the centrifuge-related activities at 7th of Tir relates to the period prior to Iran’s suspension of centrifuge activity in 2003.  Iran suspended its centrifuge manufacturing efforts for a time between late 2003 (when it also signed but did not ratify the Additional Protocol) and early February 2006, when it notified the IAEA that both its voluntary adherence to the Additional Protocol and its suspension of enrichment activity was over.  As part of these agreements, Iran revealed details about centrifuge manufacturing to the IAEA.

Under contract with the centrifuge program, DIO specialists at 7th or Tir made over twenty critical rotating components of the P1 centrifuge rotor.  According to Vienna-based diplomats present at technical briefings by IAEA officials, this facility was originally contracted in about 2001 to make 10,000 sets of these centrifuge components.

The 7th of Tir Steel Complex appears in satellite imagery as a large, gated and guarded site for missile production.  Reports indicate that centrifuge components were manufactured in several unidentified facilities within the 7th of Tir site, including a forgings workshop, a flow forming workshop, a machine shop, and a quality control laboratory.  The components were made in these facilities on high precision U.S. and European machine tools and measuring equipment.

Prior to the 2003 suspension of centrifuge manufacturing, 7th or Tir had not finished making all the components it had agreed to produce.  During the suspension, to prevent IAEA monitoring of what is a sensitive military site, Iran moved key centrifuge manufacturing equipment and components to Natanz and other sites.  It is unknown if after the end of the suspension, these items were returned to 7th or Tir, or if production was resumed on these components there. However, it is a reasonable assumption that after the suspension ended, it finished making the rest of them.

This site manufactured one of the IR-1 centrifuge’s most sensitive parts, its bellows—a thin-walled cylindrical part—made from grade 300 or 350 maraging steel. Each IR-1 centrifuge requires three bellows.  Iran illicitly purchased 67 tonnes of this super strong steel in the United Kingdom in the 1990s.  The material was in the shape of bar (about 100 millimeter diameter).  Normally, Iran would have wanted tubes, which can then be flow formed into thin-walled bellows. Maraging steel is a sensitive commodity, whose purchase is controlled by suppliers, which complicates Iran’s ability to buy it.  Iran may have found it easier to obtain if it asked for rods.  But the rod shape complicates the production of bellows.  Iranian technicians reportedly had to first use a hot lance to pierce the rod and then machine out the center into a tube.  This tube is then thinned to a wall thickness of only one millimeter on a specialized, precision flow-forming machine.  7th of Tir used a flow forming machine to do the thinning that it had obtained many years ago from the now defunct German firm Leifeld.  In total, 7th of Tir had four Leifeld flow forming machines, although only one was used to make bellows. 

Because this process of making bellows from bar is very wasteful, 67 tonnes of maraging steel is estimated as sufficient for approximately 36,000- 45,000 bellows.  Since each IR-1 centrifuge requires three bellows, Iran could make enough for some 12,000-15,000 centrifuges from this one order of maraging steel. 

Iran may have obtained additional maraging steel in the last several years.  Alternatively, it may have learned to recycle some of the large quantities of maraging steel scrap generated while making bellows. Most analysts do not believe Iran can make 300 or 350 grade maraging steel.

The U.S. Treasury Department added 7th of Tir Industries to the Specially Designated Nationals (SDN) list in 2008.  Britain, Japan, and the European Union have all listed 7th of Tir as a company of proliferation concern.

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Abzar Boresh Kaveh Co. aka Kaveh Cutting Tools

Abzar Boresh Kaveh Co, which appears to be a defense-related company, is also known as Kaveh Cutting Tools and Khorason Metallurgy Industry.1  It shares an address with Amin Industrial Group.2  Prior to Iran’s suspension of its centrifuge program in 2003, Kaveh Cutting Tools Co manufactured scoops, molecular pumps, and top flanges of centrifuges, all non-rotating components .3  It used high quality machine tools from European and other Western countries to make these centrifuge parts.  Kaveh Cutting Tools also sells products commercially, including drills, taps, cutters, reamers, and compound tools .4 It is not known if this company made centrifuge components after the suspension ended in 2006.

Abzar Boresh Kaveh Co. is named in a United Kingdom government list of Iranian individuals and entities subject to financial sanctions. Both the UK and Annex III of UN Security Council Resolution 1803 (2008) identify the firm as being involved in the production of centrifuge components. In 2009, the company was added to the U.S Treasury’s SDN list, which bans all interaction and transactions with the listed companies.5 

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1  “Iran: Names Proposed by UK and France for EU Asset Freeze and Travel Bans,” The Telegraph, February 4, 2011.
2 Office of Foreign Asset Control, “Specially Designated Nationals and Blocked Persons,” U.S. Treasury, June 29, 2011.
3 David Albright, Paul Brannan, and Jacqueline Shire, “Can Military Strikes Destroy Iran’s Gas Centrifuge Program?  Probably Not” (Washington, DC: Institute for Science and International Security, August 7, 2008).
4 Kaveh Cutting Tools website
5 U.S. Department of Treasury Office of Foreign Assets Control, “Specially Designated Nationals and Blocked Persons,” June 29, 2011.

Defense Industries Organization

Iran’s state-owned Defense Industries Organization (DIO) is one of the main subsidiaries of Iran’s Ministry of Defense.  Its primary responsibility is meeting the requirements of the armed forces of Iran, but it also exports products and engineering services.  Through its subsidiaries and contractors, it has played an important role in Iran’s development of its centrifuge manufacturing capabilities.  According to IAEA reports, substantial numbers of IR-1 centrifuge components were manufactured at DIO workshops under contract with the AEOI.  Three such workshops controlled by DIO are Khorasan Metallurgy Industries, 7th of Tir, and Kaveh Cutting Tools, all of which are named in UN Security Council Resolution 1737, Annex A

In April 2004, during a scheduled visit, the IAEA requested access to these sites and was refused.  The IAEA was granted access in late May 2004.1  According to the June 2004 IAEA report, DIO workshops were involved in the procurement of parts from abroad for the IR-2 (then referred to as the P2) centrifuge.  Initially Iran denied to the IAEA that any components had been procured from abroad.  By 2004, Iran “acknowledged that, contrary to these earlier statements, it had imported some magnets relevant to P2 centrifuges from Asian suppliers, and that the composite rotors that had been manufactured in Iran had in fact been fabricated in another workshop situated on a DIO site.”

The U.S. Department of State designated DIO on March 30, 2007 as an entity engaged in activities that have “materially contributed to the development of Iran’s nuclear and missile programs.”

DIO’s main activities involve producing defense equipment like battle tanks and other vehicles, weapons and weapons systems, as well as chemical and mechanical materials.2 

U.N Security Council Resolution 1929 identifies several other workshops as subsidiaries of the DIO.  Entities controlled by DIO include Parchin Chemical Industries, Amin Industrial Group, Kaveh Cutting tools, Shahd Sayvade Shirazi Industries, and Yazd Metallurgy Industries.3

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1Implementation of the NPT Safeguards Agreement in the Islamic Republic of Iran,” International Atomic Energy Agency, June 1, 2004.
2Defence Industries Organization
3Resolution 1929,” United Nations Security Council, June 9, 2010.

Farayand Technique

Farayand Technique is associated with Iran’s gas centrifuge program.  The IAEA states that Iran revealed the formerly secret Farayand Technique in October 2003 as part of a decision to declare far more of its gas centrifuge program to the International Atomic Energy Agency (IAEA). It was and may still be an important subsidiary of Kalaye Electric

This site has conducted quality control activities for centrifuge components, including rotors, and manufactured centrifuge components for the facilities at Natanz.  This site was initially intended as a site for centrifuge assembly, but that Iranian officials decided it was too far from the Natanz Fuel Enrichment Plant.

While Iran was trying to hide its centrifuge activities in 2003, this then secret site received centrifuge rotor balancing machines from Kalaye Electric.  This act implies that Iran expected to keep Farayand Technique secret despite the exposure of the secret Natanz and Kalaye Electric facilities. 

According to former senior United Nations officials close to the IAEA, there remain questions about the full intended role of this site.  It is also unclear today whether it continues to play a role in making and testing centrifuges, including advanced ones.

Farayand Technique is located in a valley near 7th of Tir Industries, in an industrial park. Prior to Iran’s suspension of centrifuge activites in 2003, this facility had multiple responsibilities, including making and assembling parts of the centrifuge’s bottom bearing. This part of the centrifuge is designed to hold a thin pin with a ball at its end that is attached to the bottom of the rotor assembly.  The ball, which has a complex grooving pattern, fits inside a cup filled with a specialized oil.  This design allows the rotor to spin rapidly with little friction.  Farayand Technique also performed quality testing on components manufactured in the Esfahan area, including the 7th or Tir facility, and had facilities for assembling and testing centrifuges. 

According to former senior U.N officials close to the IAEA, inspectors who visited this site during the suspension suspected that this site could have been intended as a back-up to the Kalaye Electric facility or perhaps even as a pilot centrifuge plant.  The site had two centrifuge test stands and a test pit, which would have been capable of testing centrifuges.  Next to this facility was a large building under construction, which may have been intended to be a pilot centrifuge plant. It was far bigger than the building housing the pilot centrifuge plant at Natanz.  In this case, Farayand Technique would have also served as a centrifuge assembly plant.

The IAEA conducted extensive environmental sampling at Farayand Technique.  Environmental samples taken from the balancing machines mentioned above indicated the presence of 36 percent enriched uranium.  Iranian authorities maintain that imported P1 centrifuges from Pakistan contaminated the balancing machines, a finding supported by subsequent IAEA findings. 

During the suspension of the centrifuge program between 2003 and 2006, the IAEA placed seals on P1 centrifuge components, maraging steel, high strength aluminum, and centrifuge quality control and manufacturing equipment at three sites, including Farayand Technique, to ensure they were not used to make more centrifuge parts.  When Iran resumed enrichment activities in January 2006, it removed the seals from the equipment under the supervision of IAEA inspectors.  The IAEA has not visited this site since then.

Farayand Technique is sanctioned in UN Security Council Resolution 1737 and U.S. Executive Order 13382.

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1 IAEA Board of Governors, Implementation of the NPT Safeguards Agreement in the Islamic Republic of Iran GOV/2004/11.  February 24, 2004.
2 IAEA Board of Governors, Implementation of the NPT Safeguards Agreement in the Islamic Republic of Iran GOV/2004/11.  February 24, 2004.
3Chronology of Key Events (January – December 2006)”  IAEA and Canada

Kalaye Electric Company (also known as Kala Electric)

According to IAEA reports based on interviews with Iranian officials, Kalaye Electric Company, located in Tehran, was Iran’s primary centrifuge research and development site in the late 1990s and early 2000s, until Iran moved operations to the Natanz site in 2002.  Iran operated this site in secret in violation of Iran’s commitments under its safeguards agreements with the International Atomic Energy Agency (IAEA).  In 2003, it revealed the true nature of the site only after the site was exposed publicly, and Iran was subjected to intense international pressure.

Based on Iran’s revised declaration about this site, originally, Kalaye Electric was a private company that was bought by the Atomic Energy Organization of Iran (AEOI).  The name “Kalaye Electric” means “electric goods,” implying that Iran kept the original name to help disguise the true purpose of the facility.

Iran declared that Kalaye Electric became the primary IR-1 centrifuge development and testing site after such work was moved in 1995 from the Tehran Nuclear Research Center.  The IAEA has reported that between 1997 and 2002, Iran assembled and tested IR-1 centrifuges at Kalaye.  Iran used 1.9 kg of imported, undeclared Chinese uranium hexafluoride to test centrifuge machines at the Kalaye Electric Company workshop between 1999 and 2002, before dismantling the centrifuge test facility at the end of 2002.

Public investigations of the site began after the publication of information about secret Iranian enrichment activities.  The first organization to name the facility publicly was the National Council for Resistance of Iran (NCRI), which did so in early 2003.

Following the public revelation of Kalaye Electric, media reports indicated that U.S. satellite imagery showed considerable activity, suggesting that equipment was removed from the site and raising suspicions that Iran was attempting to hide activities before granting access to the IAEA.  The IAEA asked to visit Kalaye Electric in February 2003 and to take environmental samples to determine if any enriched uranium was produced at the site. Iran responded that the facility was a watch factory, but that it also made a few centrifuge components. It initially denied the inspectors’ requests to take environmental samples, claiming that it did not have to allow access until Iran implemented the Additional Protocol.

Under intense international pressure, Iran subsequently relented and allowed the IAEA limited access in March 2003 and full access in May, but it refused to permit environmental sampling until August 2003. Iran took extraordinary steps to disguise the past use and purpose of this facility, including removing equipment and reconstructing the interior of the main building.  Nonetheless, the IAEA was able to detect enriched uranium at another building at this site, further pressuring Iran to declare fully its activities there and elsewhere.

Since moving many centrifuge research and development activities to the Pilot Fuel Enrichment Plant (PFEP) at Natanz, Kalaye Electric has remained an important centrifuge research and development site. 

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Khorasan Metallurgy Industries

Khorasan is identified in Annex III of UN Security Council Resolution 1803 (2008) as a firm involved in the “production of centrifuge components” and subsidiary of the Ammunition Industries Group (AMIG) and Defense Industries Organization (DIO).

Kaveh Cutting Tools Complex, a part of Khorasan Metallurgy Industries, northeast of Tehran near the city of Mashhad, made the P1 centrifuges scoops, molecular pumps and other components. These are all stationary components in a centrifuge and easier to make than the rotating ones.  For other companies involved in manufacturing centrifuge components, see this page.

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Kolahdouz is a military industrial complex located in western Tehran that was initially inspected by the IAEA in 2003 after the National Council of Resistance of Iran identified it as a site of covert development of centrifuges for uranium enrichment.  The IAEA’s November 2004 report notes that on a visit “no work was seen at those locations that could be directly linked to uranium enrichment” and that environmental samples did not reveal “any indication of activity involving the use of nuclear material.”

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The Natanz Fuel Enrichment complex is the primary site of Iran’s gas centrifuge program. It contains two primary facilities:  the Pilot Fuel Enrichment Plant (PFEP) and the Fuel Enrichment Plant (FEP).  It also houses a centrifuge assembly area.  The two primary facilities, as well as other buildings at the Natanz site, can be seen in satellite imagery below.

On March 30, 2005, then President Mohammad Khatami toured the Natanz site accompanied by the media.  This tour produced the first publicly available ground images of Natanz.  A subsequent visit by President Mahmoud Ahmadinejad in 2008 led to many images of the complex and centrifuges in the pilot plant. 

The Natanz facility was first publicly identified by the National Council for Resistance of Iran (NCRI) in August 2002.  At that time, NCRI identified the facility as a nuclear fuel fabrication plant.  In December 2002, ISIS released satellite photos of the facility for the first time and correctly identified the site as a gas centrifuge enrichment facility.

Natanz Fuel Enrichment Plant

The Natanz Fuel Enrichment Plant (FEP) is Iran’s largest gas centrifuge uranium enrichment facility. It consists of three large underground buildings, two of which are designed to be cascade halls to hold 50,000 centrifuges.  The buildings started as 70 foot deep holes, and satellite imagery showed the construction of thick concrete walls. The FEP began operating in February 2007, and construction on centrifuge cascades is ongoing. The FEP ostensibly exists to produce enriched uranium for light water reactors in Iran, including the Bushehr facility and others that Iran has not yet built.

Iran uses the FEP to produce 3.5 percent low-enriched uranium (LEU) for its nuclear program. Until early 2013, it installed only IR-1 centrifuges in single 174- and 164- machine cascades. Iran announced to the IAEA on January 23, 2013 that it intended to install IR-2m advanced centrifuges at the FEP.

Natanz Pilot Fuel Enrichment Plant

The Pilot Fuel Enrichment Plant (PFEP) is Iran’s centrifuge research and development facility which uses uranium hexafluoride.  Iran has other facilities, mostly unknown publicly, which conduct important tests of centrifuges without introducing uranium hexafluoride.  More is known about the PFEP than other centrifuge manufacturing facilities because its use of uranium hexafluoride requires inspections by the IAEA, which then reports publicly on activities there.

In 2002, Iran moved gas centrifuge research, development, and assembly operations to this facility from Kalaye Electric, its then secret site near Tehran. The PFEP is an above-ground building at the Natanz Fuel Enrichment complex. 

Iran tests centrifuges of various models, including its deployed IR-1 and IR-2m, but also more advanced designs, in single machine, small cascades, and production-scale cascades at the PFEP. Typically, in the test cascades, Iran recombines the product and tails from these cascades, so no enriched uranium is produced.

Since February 2010, Iran has produced 19.75 percent enriched uranium in a set of two, 164-machine IR-1 cascades oriented in tandem, ostensibly for the Tehran Research Reactor (TRR).  One of these cascades enriches from 3.5 percent LEU to almost 20 percent low enriched uranium (LEU), while the second one takes the tails from the first and outputs roughly 10 percent LEU and a tails of natural uranium.  The ten percent material is fed into the first cascade in addition to 3.5 percent LEU.  This process allows Iran to more efficiently use its 3.5 percent LEU stock.

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Pars Trash (Tarash)

Pars Trash, a subsidiary of Kalaye Electric located in Tehran, is a centrifuge site that received equipment from Kalaye Electric in particular for Iran’s centrifuge manufacturing and development effort.

Pars Trash, a small company employing about ten people, is located in Tehran among warehouses and light industrial buildings about a kilometer west of the Kalaye Electric facility. It manufactured centrifuge outer casings. These are the thick aluminum tubes that house the centrifuge rotor assembly and, in the case of an accident, prevent broken pieces of the thin-walled rotor assembly, which can act like shrapnel, from injuring or even killing bystanders. Pars Trash was originally a small, private factory involved in making automobile parts. It went bankrupt and was bought by the Kalaye Electric Company, or its subsidiary Farayand, for the three expensive computer-operated machine tools it owned, which could be adapted for the manufacture of centrifuge components.

An engineer married to the plant manager is believed to have been the backbone of the operation. She programmed and set up the machines to make centrifuge components and ensured their quality, before turning the operation over to a technician who subsequently operated the automated machines to produce thousands of components.

In February 2003, Pars Trash was involved in Iran’s concealment efforts.  The facility stored equipment that Iran had hastily moved from the Kalaye Electric site in an attempt to prevent its discovery by IAEA inspectors who were seeking access to Kalaye Electric.  Subsequently, under intense international pressure, Iran revealed these and other concealment activities to the IAEA.

The current status of operations at Pars Trash is unknown, as IAEA inspectors had access to the site only while Iran was adhering voluntarily to the suspension of its centrifuge program and the Additional Protocol, a status that ended in 2006.

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Sanam Electronic Industry Group

Sanam Electronic Industry Group in Tehran was another DIO-associated facility involved in the manufacture of centrifuge components.

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TABA Facility

The TABA facility, once known as the Iran Cutting Tools company, reportedly makes centrifuge components.  The exact type of components and number made remain uncertain.  In particular, it is unknown if this site has made the more sensitive rotating components of centrifuges. 

Iran stopped informing the International Atomic Energy Agency (IAEA) about the locations of its gas centrifuge component manufacturing and assembly facilities in 2006.  In the past, Iran has utilized existing commercial and military industries to manufacture centrifuge components.  As such, it is plausible that the TABA facility makes centrifuge components for the Atomic Energy Organization of Iran (AEOI) under contract.

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