Cleaning, regular maintenance pay dividends for blow molders

Oct. 21, 2020
Recommendations from Amsler and Jomar representatives include daily machine inspections, regular greasing and monitoring of fluids.

PMM Staff Report  

Experts at blow molding machine manufacturers agree that scrupulous maintenance practices — ranging from basic to high-tech — are the key to minimizing unexpected downtime and prolonging machine life.  

Starting early 

Good preventive maintenance needs to begin before the owner takes possession of a new blow molding machine, said David V. Shearer, customer service manager at Jomar, which makes injection blow molding machines. 

“Many customers, even today, buy brand-new equipment without thought to the maintenance needs of the new equipment,” Shearer said. “It is important to get the need for proper preventive maintenance established before the customer purchases equipment and experiences avoidable breakdowns early in the machine’s career.”

Successful processors make themselves knowledgeable about their machines in advance, practicing preventive, and with enough experience, predictive, maintenance, Shearer said. “Customers who fail to perform PM are usually spending inordinate amounts of money and suffering lost production time making machine repairs instead of product,” he said. 

Shearer gave an example of the cost of overlooking basic maintenance 

“I had to take a shaft out of a fairly young machine because the end user neglected to apply lubrication for about 12,000 hours of operation. When we went to pull the shaft out, the machine moved first,” Shearer recalled. “The whole fiasco cost the customer weeks of downtime and more than $50,000 in parts and labor to put the machine back in operation.” 

High-tech methods 

More-sophisticated technology also has its place in a good maintenance program, according to Bruce Coxhead, CEO of Amsler, which specializes in manufacturing PET stretch blow molding machines and auxiliary equipment. 

“Introducing a monitoring SPC [statistical process control] process will show trends when something is going off spec,” Coxhead said. “This is a sign that something has happened to the machine.”  

There are other important clues as well: “Things like broken bulb detection and loss of waterflow can all signal the operator to stop and repair,” Coxhead said. 

Shearer said machine downtime can be virtually eliminated if users apply Industry 4.0 technologies for predictive maintenance. He said the key is to follow the guidance of the new technologies that are being integrated into control systems. 

Back to basics  

But there is no substitute for reading the manual, keeping the machine clean and documenting upkeep. 

Coxhead stressed the need for keeping maintenance logs on each machine and having signals that tell operators when action is needed and what to do.  

Machine cleanliness also is vital, he said. “Dirty molds create bad bottles. Molds must be cleaned daily and when they are put into storage and again when pulled out of storage. All waterlines must be dry.” 

 He listed his top tips for keeping a blow molding machine running smoothly:  

  • Follow the manual’s maintenance guidelines.  
  • Purchase the recommended spare parts.  
    • Do daily walks around the machine and the resin-handling system, checking all safety equipment. 
      • Ensure the resin is correct for the job.  
        • Make sure the operator is trained and knows to listen for weird noises.  

          Ensure all fluids are clean.  

          Shearer also provide top tips: 

          • Keep it clean. Address any oil leaks as soon as possible and change oil filters before dirty oil creates even more leaks. Dirty grease is not a lubricant, it is a polishing paste gone wrong and will accelerate wear.  
          • Keep it cool. Modern hydraulic systems with proportional and servo valves are tuned to operate with a specific fluid within a specific temperature range. If the oil is too hot, the oil will lose viscosity and lubricity, accelerating wear. 
            • Grease it. Pennies-worth of grease can save thousands of dollars in downtime and lost production. 
              • Look at the machine every shift. Indicator lights, pressure gauges, timer displays and sight glasses show how the machine is doing.  
                • Listen. Know what the machine is supposed to sound like. If it sounds off, chances are there is a problem.  

                  Following these practices will reap dividends, Shearer said. “A lot of Jomar customers are still running machines daily that are 30, 40 or even in rare cases almost 50 years old. A talented mechanic can keep a Jomar running his entire career.” 


                  W. Amsler Equipment Inc., Bolton, Ontario, 905-951-9559,

                  Jomar Corp., Pleasantville, N.J., 609-646-8000,