Hydraulic presses are a staple in the stamping field offering unique benefits and features especially when it comes to deep-drawen parts. But many offer other benefits that can help companies gain productivity and reduce maintenance.
Greenerd Press and Machine Company Inc. has increased the tonnage capacity of their hydraulic presses and now offers even more precision in their press controls. Greenerd custom designs and builds hydraulic presses up to 3,000 tons in their Nashua, NH facility. The company has also developed a relationship with Tianjin-Tianduan Press Company, the largest hydraulic press manufacturer in China. This increases Greenerd’s range from 3 tons to 40,000 tons, says Tim Dining, Greenerd’s president.
“At our Nashua facilty, we can build bed sizes customized to the application,” says Dining. “The largest we’ve built in the last several years has been 8 ft. by 33 ft. long. This was a gantry-style press with a pressing head that travels along the head plate,” he says.
Greenerd has also built a number of hydraulic straightening presses using a gap-frame-press design with an extended bed. “This gap-frame press might only have a platen that is 36 in. wide and a bed that is 12, 14 or 16 ft. wide. We also build gantry-style straightening presses in a tonnage range from 20 to 600 tons,” he mentions.
Greenerd writes its own programs using Allen Bradley control equipment for its presses. “What this means for our customers is it enables us to provide immediate service and support when needed. Since 2003 we’ve also been working with remote communications, which is an area that has had great interest recently. This allows us and our customers to monitor presses online,” mentions Dining.
Remote communications provides the capability to obtain a real-time status of press operations by logging in and viewing data from presses via an Ethernet connection over a secure VPN network. For example, this capability allows a press to send an e-mail message to the press control and the operator when an alarm is triggered. One such example might be when the oil temperature is getting too high, says Dining.
“This is a great service and capability for the end-user. It’s become much more common as a new and improved means for communicating remotely with our presses,” he says.
Dining remarks that this press communication option is available when a customer has a new press built, and it can also be added as an upgrade for existing presses.
Greenerd has the capability to manage press automation. “We’ve seen a lot more interest in the last two years for integrated solutions,” says Dining. “The robust nature of the PLC we use allows us to either act as the master or slave to an overall system wherever the press is located. We can offer just the press control, or if the customer wants us to integrate a transfer system, indexed table or robotic-vision system, we can integrate all this including the control for example.”
Dining notes that their customers tend to purchase a hydraulic press over a mechanical one because of flexibility and versatility. He remarks that hydraulic presses can offer a lower cost press compared to servo-driven ones.
“We can offer a motion profile that is adjustable, and it can be modified from one part to the next. Also, each stroke profile can have multiple steps. Compared to a mechanical press, the primary advantage is that we offer full tonnage anywhere within the stroke where a mechanical press can’t.
“Hydraulic presses are becoming faster and faster, because of new and better valves and pumps that are available. These are superior to previous designs and provide tighter control with the ability to operate at different pressures. Also, more powerful press controls are becoming more affordable,” he concludes.
Greenerd Press & Machine Company Inc.