Faster blasting, less maintenance: equipment upgrade cuts Dalian Maruyuu’s shot blast cycle time by 40%


Founded in July 2003, Dalian Maruyuu Metal Co., Ltd is located in the city of Dalian, in Liaoning Province, China. It manufactures iron blanks and castings for automotive, motorcycle and other customers along with metal and wood moulds, producing a total of 40,0000 tons of castings annually.

For almost 20 years, the foundry has relied on Wheelabrator’s hanger type (HT) shot blast machines for reliable and economical blast cleaning of castings. HT machines are the most flexible type of blast equipment, able to cope with small, medium and very large parts in batch or continuous operation. Dalian Maruyuu is using equipment modernisation programmes (EMPs) to bring the performance of its oldest HT machines in line with newer models.

The Dalian Maruyuu foundry employs five sets of Wheelabrator HT machines, with the oldest two dating back to the start of production in 2004. The three most recent machines (purchased in 2011 and 2015) were performing well but, after nearly two decades of constant operation, the oldest two HT machines’ blast efficiency was lower. There was also some abrasive leakage and the foundry was concerned that this did not comply with the latest safety standards.

“In 2021, we consulted with Dalian Maruyuu and proposed an EMP for one of the machines,” says Leon Gu, VP After Sales, Wheelabrator Asia Pacific. “Carrying out an EMP for existing shot blast equipment can increase its productivity, efficiency and cost-efficiency – or all three at once. An EMP also avoids the expense and downtime involved in procuring and installing new equipment or in reconfiguring a factory layout so that extra equipment can fit in.”

Universal blast wheels: high efficiency, minimum maintenance

“The main part of the EMP involved upgrading the HT’s blast wheels from the original eight SRD380 blast wheels to six U70x380 wheels,” says Lucas Li, Sales Manager, Spare Parts Wheel, Wheelabrator Asia Pacific. “These modern U-type wheels are the same type as the ones fitted to Dalian Maruyuu’s other, newer HT machines and offer higher performance.”

Wheelabrator’s compact Universal wheel design features double discs with eight blades each, giving improved intensity of abrasive distribution (optimised throwing angle and intensity peak) that ensures maximum cleaning efficiency. Proven in numerous applications, they can operate under difficult conditions with long maintenance intervals and, with their easy accessibility, require minimal maintenance time.

Maruyuu BeforeAfter

“Their greater intensity and efficiency is why we could use six Universal wheels to replace eight SRD wheels and achieve the same surface cleaning standard with a shorter cycle time,” says Lucas Li. “As part of the EMP, we also helped the customer to change the abrasive recycling system.”

EMP cuts cycle time by 40% and maintenance by 20%

“Following the EMP, shot blasting cycle time dropped dramatically, from 1000-1200 seconds to 600-800 seconds,” says Lucas Li. “The volume of maintenance and part replacement required also dropped by 20%, cutting the same amount – 20% – from maintenance downtime.”

The new, completely sealed, abrasive recycling system also improves safety and gives a cleaner working environment.

The blast results were exactly what we had told the customer to expect and, after the EMP, there was no shot leakage at all,” says Leon Gu. “They were very pleased and have just signed the contract with us to upgrade the other HT machine as well. We will use four U wheels to replace the five existing SRD wheels and will deliver the EMP project later this year.”

After this last EMP, all HT machines at Dalian Maruyuu will feature the same U-type blast wheels, which further simplifies maintenance and helps the customer reduce the cost of spare parts.