The maintenance department at Blank Park Zoo ( in Des Moines, Iowa was looking for a cost-effective way to keep their train running safely. The train ride is part of the 49-acre park which includes almost 1500 animal specimens.

Chug-a Chug-a Choo Choo!

The train ride runs over eight hours a day, every day from April through October. In operation since the 1960s, the older of the two engines has been in service for over 50 years. Use and required preventative maintenance was wearing out components, especially the air brake cylinders on the train.

choo-choo train

The Blank Park Zoo scenic train ride includes two train engines and five passenger cars. Each engine and car includes two sets of dual axles (four wheels) connected to a pivoting frame or truck. Each of the eight wheels on an engine or car has an air brake, for a total of 56 brake pads and cylinders on the train.

Just like a large passenger or freight train, the brake shoe directly contacts the train wheel. When the engineer operates the train brake, air is supplied to all 56 pneumatic brake cylinders. Each cylinder pushes a lever to apply a brake shoe to a train wheel.

brake cylinders

The original cylinders were dated, as was the cylinder design, and they required replacement, which was going to be very expensive. Maintenance Manager Allen Schroeder determined the original brake cylinder bore and stroke requirements and found, as a suitable replacement, NITRA pneumatic air cylinders and related pneumatic components on AutomationDirect’s web site. The zoo’s maintenance department then retrofitted the train engines and cars with NITRA cylinders.

cylinder rod The new NITRA cylinders are 1-1/2 inch bore, 1 inch stroke, single-acting/spring return with a rear-pivot mount. A NITRA rod clevis connects the cylinder rod to the brake lever, and a ¼ inch thick brackets are used to mount the air cylinder to the truck frame.

The new AutomationDirect NITRA cylinders are reliably stopping the train quickly. Delivery from AutomationDirect was quick as well, taking only a few days compared to the weeks needed for the original cylinders. And even better, the new cylinders cost 80% less than original cylinders, saving $11,000 once all 56 cylinders are installed. Woo, woo!

For more information, please see the article Stop the Train! in the March/April 2017 issue of IEN, authored by Allen Schroeder, Maintenance Manager at Blank Park Zoo.