Pump sensors and controller deployed to power car plant HVAC

Paul Boughton
During the design phase of a new automobile factory in Shanghai, ITT Industries' Bell & Gossett unit was called in to resolve HVAC system problems. The result is an advanced and efficient set of pumps sensors and controller that power the HVAC system for the large industrial facility.

Shanghai General Motors Co Ltd (SGM) is a 50-50 joint venture with the US car giant, General Motors and Shanghai Automotive Industry Corporation Group (SAIC), the leading passenger car manufacturer in China. The largest automotive joint venture in China, Shanghai GM was formed in June 1997. It manufactures a family of Buick products, as well as engines and transmissions. Shanghai GM is fully supported by a network of sales, aftersales and parts centres. Shanghai GM has an annual production capacity of 200000 vehicles operating on three shifts.

With sales success came the expansion of production facilities in Shanghai. SGM's latest expansion is the South Plant. Covering 230000sqmeters, the plant is equipped with the most advanced automobile production line and equipment. Five main workshops adopt the management process of modularised design and flexible production lines to satisfy the variable requirements of the market by producing several different model cars in single production line. The new SGM factory was formally put into production in July 2005 and produces luxury Cadillac model cars. The output of the new SGM factory is predicted to reach 200000 cars per year.

In the first phase of the factory construction, the HVAC system was equipped with pumps and common variable speed control facilities. After tests, during the design period, the HVAC equipment supplier was not able to resolve a number of unsatisfactory phenomena and performance problems. In order to resolve these system problems, the plant's master designer began a process of engaging HVAC experts and investigating alternatives.

Educating HVAC professionals

In China, ITT Bell & Gossett unit is looked at as an educator and expert in HVAC equipment and system analysis as well as a manufacturer. Every year, an instructor from Bell & Gossett holds seminars and advanced lecture series around China for HVAC designers and ITT Bell & Gossett distributors. This education is builds on the 50-year history of the 'Little Red Schoolhouse', a centre for HVAC education that ITT Bell & Gossett runs from its headquarters near Chicago. The master HVAC system designer in charge of the SGM project was invited to attend the ITT Bell & Gossett seminar held in Nanjing. The principles, formulations and systems analysis shown in the seminar ultimately satisfied the master designer that ITT Bell & Gossett could resolve the HVAC system problems at the auto plant.

After the seminar, discussion began with SMG regarding the HVAC system of new factory. Piping layout drawings and system drawings were analyzed and ideas were shared to solve the HVAC design problems.

Variable speed drives save energy

Powering the huge HVAC system in the auto factory is the power plant, which takes up 5000squaremeters. This plant includes seven 2000-ton chillers and three 400-ton chillers.

Tying these chillers into the plant's HVAC system are ITT Bell & Gossett's primary and secondary systems with variable speed design. Integrated into the new factory's HVAC system is a large contingent of ITT Bell & Gossett pump system including nine large ITT Bell & Gossett Series VSCS pumps, 14 Series HSCS horizontally split pumps and 14 Series 1510 base-mounted end suction pumps.

The pumps are controlled by the primary and secondary variable speed system and provide the factory with excellent energy saving. Pressure sensors were placed in a number of positions throughout the plant and these sensors pass a signal to controllers. The controllers then change the frequency of the variable speed drive to the pump's rotation speed control, allowing an accurate flow in the HVAC system. In a comparison to the variable transmission that many cars are now equipped with, the ITT Bell & Gossett systems can provide the factory's HVAC system with any capacity of flow by changing the pumps' rotation speed. The initial cost of the variable speed controller equipment is offset within short running period by minimising energy expense.

A local team including Fluidtech, the ITT Bell & Gossett distributor in Shanghai and Mr Alex Jiang, the ITT Bell & Gossett sales manager in Shanghai, assisted the SGM design engineers and successfully finished the HVAC primary-secondary variable speed system design for the factory.

The new auto factory is one of a series of high profile installations of ITT Bell & Gossett systems in China including the Shanghai Science Museum. With the auto factory in operation, the future for Shanghai GM looks very bright. In 2004, Shanghai GM sold 252869 vehicles. This was a 25.7 per cent increase over the previous year, placing Shanghai GM among the top three passenger car manufacturers in China.

ITT Bell & Gossett unit is a world leader in pump products for the liquid-based HVAC industry. ITT Bell & Gossett serves the HVAC industry with world-class fluid handling products in markets from large commercial HVAC applications to pumps and valves used in residential hot water heating.

For more information, visit www.bellgossett.com