Materials handling plays a key role in the day-to-day operations of every foundry. Whether moving materials into a plant, transferring it within the plant, or shipping finished goods out the door, materials handling is vital to the inner-workings of foundries. The North Manchester Foundry of North Manchester, Indiana, is no exception to this rule.

The facility manufactures and heat-treats an average of 70 tons of rough gray iron, ductile iron, and stainless steel castings per day. The castings are used in wide range of industries including the automotive, agricultural, boating and plumbing industries. The facility uses approximately 50,000 pounds of dry sand per day in their molding processes.
Pneumatic Sand Delivery

The sand, which plays a critical role in determining the strength and hardness of the castings, is pneumatically unloaded from the delivery truck at a pressure of 10-15 psi into a 4" diameter sand transporter line. Pneumatic conveying systems are based on fully or partially aerating the material, such as sand, to push it through a pipeline. In North Manchester Foundry’s case, the pipeline was originally schedule 40 pipe. Eventually, such pneumatic systems are prone to abrasive wear, especially when moving sand, even if extra-heavy pipe is used.
Excessive Abrasion

In 1988, the North Manchester Foundry was having problems with the pneumatic system due to excessive abrasion in two 90° elbows. Operations were interrupted on a regular basis so the elbows could be patched and eventually completely replaced. However, this remedy only lasted two years. Joe Brubaker, North Manchester Foundry’s maintenance foreman for the past 24 years, decided that a more permanent solution needed to be found.

“We knew that changing our method of transport (by replacing the pneumatic pipe system) was cost prohibitive,” said Brubaker. “But the elbows were going to continue to wear through because of the impact they sustained as the sand changes direction.”
ALRESIST High Alumina Ceramic-Lined Products

In 1990, Brubaker was approached by Abresist Corporation, the U.S. Subsidiary of Kalenborn Kalprotect, the German developer of ABRESIST® abrasion resistant materials. The Urbana, Indiana, company manufactures ALRESIST high alumina ceramic-lined products made from fine grain, alpha aluminum oxide. The alumina linings are rated 9 on the Mohs hardness scale, higher than any other material with the exception of diamond which is 10.

Working with the foundry, Abresist Corporation designed, fabricated and delivered two 4" ID x 90° elbows, 24" radius. The elbows were lined with 1" thick alumina cylinders installed in 10 gauge steel casings equipped with rotating flanges. Weld-on adaptor flanges were used to connect the oversized flanges to the schedule 40 straight pipe.

According to Abresist sales representative, Gary Hensley, “Abrasion is a common problem at most foundries in the pneumatic conveying of sand. The key to longer life in this abrasive situation was to provide a lining harder than the silica sand, and alumina does that.”