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Ringing in the Future, and the Past

June 4, 2004
Science and faith come together, as Inductotherm engineers design a special melting furnace for a project to recreate an important artifact of Russias past.

In Russia in the the mid-1700s, a four-hundred year old monastery at Trinity Sergeeva Laurel was the educational, cultural, and power center of the Russian Orthodox Church. Its churches and cathedrals were famous for their splendor and richness.

In 1746, with the financial support of Empress Elizabeth, the Church undertook a grand project to cast a 65-metric ton bell. Monastery records indicate that the first attempt in May-June 1746 was not successful. Two years later, on September 10, 1748, furnaces were fired again and on September 12 the magnificent Tsar bell was cast. Three thousand people took part in this endeavor, under the leadership of Russian masters Gabriel Smirmov and Semeon Stepanov. No other bell in the world was as large, nor had such intricate ornamentation.

The journey from the foundry to the monastery took more than a year. In February 1750, the bell finally reached Laurel and was mounted on temporary oak supports. It took another nine years to modify the bell tower and lift the Tsar bell to its permanent location. In December 1759, using a specially designed machine operated by 300 people, the bell was finally installed.

Although a larger, 200-metric ton Tsar bell was cast in Moscow, it cracked before it could ring for the first time. That bell is permanently and silently displayed in the Kremlin. The Tsar bell at Trinity Sergeeva Laurel tolled in harmony with the 20-metric ton Karnauckhi bell, the 32-metric ton Godunov bell, and 25 other smaller bells — until they were silenced in 1920.

Death and rebirth

Soon after the Bolshevik Revolution, dark ages descended on Laurel. In their atheist fervor, the Communists closed the monastery. Priests were killed, the churches and cathedrals were looted. One cathedral and bell tower was demolished. The bricks were used for a silo and a chicken-processing plant.

In the winter of 1930 they came for the bells. On January 28, the Tsar bell was thrown from the tower, though it survived the fall to the frozen ground. The Godunov and Karnauchi bells were dropped on top in an attempt to break the Tsar bell, though they merely cracked it. Next, to finish the task, looters attacked the bell with sledge hammers. Michael Prishvin, who witnessed the destruction, noted in his diary that “the groan was powerful and prolonged. This looked very much like a public execution.”

Finally, the Soviet Union crumbled in 1991, and Russians’ religious life began once again to flourish. Trinity Sergeeva Laurel and many other houses of worship began rebuilding. In 2002, at the Moscow Automobile Works, two new bells were cast to replace the ones destroyed in 1930. The Karnauchi bell was replaced by a 27-metric ton Pervenetz (“first born”) bell and the Godunov bell by a 35.5-metric ton Blagovestnik (“bearer of good news”) bell.

Recreating a masterpiece

In 2002 the Russian Orthodox Church decided to cast a new Tsar bell and place it where its famous predecessor once hung. Professor Boris N. Nunin, director of the Association of Ancient Russian Music, calculated that to sound in unison with other bells on the tower, the new Tsar bell should be 4.55 meters in diameter and 4.42 meters high, and weigh 72 metric tons. To cast the bell nearly 85 tons of molten tin bronze should be poured into the mold very quickly (under 30 minutes) and topped off with an additional 15 metric tons soon after, to minimize distortions that occur when bronze solidifies.

The Church offered the project to Baltiskiy Zavod in St. Petersburg, Russia’s oldest and largest shipbuilder. A team was assembled at Baltiskiy under the leadership of chief metallurgist Rostislav Gusev and his son Maxim. Soon, though, they realized that even though the shipyard’s melt shop cast propellers for the largest nuclear subs and aircraft carriers, it did not have the capacity to melt enough bronze at once to cast the bell. All the Baltiskiy Zavod furnaces operating together could melt no more than 60 tons.

A partnership

To add melting capacity, Baltiskiy enlisted Inductotherm to build a special 25-metric ton induction furnace. The contract was placed in March 2003. The furnace was built in a record three months’ time, and shipped to Russia in May 2003.

While Inductotherm built the furnace, the masters at Baltiskiy were constructing the mold. Workers machined a wooden bell form on a gigantic vertical lathe. Sculptors Edward Ladigin and Andrew Zabaluev shaped wonderful wax reliefs reflecting the history of the monastery on the form’s surface. They placed images of Church patriarchs Alexis I, Alexis II, and Peamen, along with Saint-Archimandrite Platon among sixteen Russian saints. A beautiful inscription below the images details that the bell was cast during the reign of Patriarch Alexis II over the Russian Orthodox Church and the presidency of Vladimir Putin. The inscription also lists Archimandrite Feognost, the present head of the Trinity Sergeeva Laurel monastery, as a leader of the project , and other major contributors, as well.

The furnace was installed and trials were run during July and August, and finally the melting was set to begin.

The casting of the bell was initially scheduled to take place on August 26, 2003. Unfortunately the attempt was not successful. Unaccustomed to such powerful equipment, the workers melted the bronze too quickly and the furnace refractory had not cured properly. Molten metal dripped from the bottom of the furnace. An electronic control device powered down the furnace, and the casting attempt was aborted.

Inductotherm was notified of the situation, and the firm’s vice president and chief technology officer were dispatched to St. Petersburg immediately. At the Baltiskiy plant, workers and Inductotherm engineers fixed the furnace. A new refractory was installed, preheated, and sintered properly. The casting of the bell was rescheduled for September 10, 2004.

Casting the new bell

Preparations began after midnight, September 9. Nine furnaces, including the new Inductotherm furnace, were to be used for a total maximum capacity of 85 metric tons. For 36 hours straight Baltiskiy workers and Inductotherm engineers monitored the equipment to ensure that refractory preheating progressed according to schedule. All the while, the priests from Trinity Sergeeva Laurel held an prayer vigil on the melt deck for a successful casting.

On the morning of September 10, all the furnaces were nearly full of molten bronze when an older, six-metric ton furnace developed a metal leak through the refractory. It had to be shut down. This was critical, because without this furnace the casting would be six tons short of the required metal and the attempt to cast the bell would have to be abandoned again.

Recalculating, Inductotherm engineers determined that their new furnace could be loaded to hold 31 metric tons. They gave the word to charge an additional six metric tons into the 25-metric ton vessel. At about 3:00 p.m. the furnaces were emptied into four 25-ton ladles and the metal was poured into the bell mold.

The casting process took less than 23 minutes. This time, it was successful.

Later that day an official reception was held at the Baltiskiy plant. Russian Orthodox Archimandrite Feognost, pronounced a church blessing on the bell’s creators, the workers, and the Inductotherm engineers who worked to create this sacred relic for the Russian faithful. The monastery chorus sang special psalms wishing a long life to the Baltiskiy workers and Inductotherm staff. And, Feognost and the priests and monks of the monastery prayed for a divine intervention to help them cast the bell successfully. The date, September 10, 2003, was exactly 255 years from the day the metal was melted to cast the original Tsar bell.

Their prayers were answered.

The journey home

The casting of the large bell cooled slowly. Two weeks later, when workers tried to open the mold they found the casting was still red hot and the mold was closed for two more weeks. Finally, the mold was opened to reveal the beautiful bell and all its perfect details. Another ten weeks were spent cleaning and polishing the new relic. A patina coating was applied, and finally the time arrived to ring the bell for the first time. The melodious sound was as beautiful as its appearance. No tuning adjustment was necessary.

On January 9, 2004, the Tsar bell was loaded on a truck and slowly moved out of the Baltiskiy plant. Police blocked traffic and electric power crews lifted high-voltage lines that crossed the roads traveled by an escorted semi-trailer carrying the bell. Despite the late hour and bitter cold, citizens of St. Petersburg lined the streets to see the procession. Guns on the city’s famous Peter and Paul fortress fired a farewell salvo for the passing convoy.

The scene was telecast around the world, and repeated in many Russian towns and villages along the way. After a week-long journey the bell finally reached Trinity Sergeeva Laurel. The monastery gate was widened to allow the precious cargo to pass through.

Finally, on April 16, the bell was lifted into the belfry of the church tower where its predecessor had tolled for 168 years. Witnesses say that the excitement of the day was not dimished by gray, overcast skies. But, fittingly, as the new Tsar bell was hoisted into place a brilliant sun broke through the clouds to shine on it. The restoration was complete. A new era began.

One of a kind Design

The 25-ton bronze-melting furnace described in this story is a one-of-a-kind design that Inductotherm engineers developed and built for the Tsar bell casting program at Baltiskiy Zavod, in St. Petersburg, Russia. The furnace was designed with a wide-body hearth that can be charged with large chunks of scrap, up to 2.75-meters in diameter, according to Inductotherm’s group vice president Dr. Oleg Fishman.

The Inductotherm Group companies supply melting and heating equipment for the global metals industry. The organization has 50 wholly owned companies operating in 18 countries. It claims among its significant achievements in automated thermal processing:

  • The most powerful medium-frequency induction melting furnaces, such as Powertrak® VIP®, with output power up to 20,000 kW and melting rates of 52,500 kg/hour.
  • The Visipour® system, which fills molds accurately, with real-time electronic vision control.
  • Dualtrak®, an innovative method for overlapping batch melting from two furnaces using a single, dual-output power supply.
  • And, the largest upright channel furnaces available, in capacities up to 150 metric tons.