News | October 12, 2018

Pump Shop Eases Production Pressure With Multi-Tasking

Back in the late ‘90’s when MTH Tool Co. first considered incorporating multi-tasking machine technology into its shop’s pump manufacturing operations, most people thought that multi-tasking equipment was too cumbersome to setup and difficult to program. Fortunately, Tim Tremain, President of MTH, ignored those concerns and installed the shop’s first multi-tasking machine tool with gantry robot in 1998.

Tremain hasn’t looked back since, because with that technology, the Plano, Illinois-based shop has all but eliminated work in progress (WIP), reduced the need for any in-process work handling and significantly increased its output without additional equipment or machining personnel. All while slashing job setup time, improving part tolerances and boosting concentricity in addition to ensuring process consistency.

Before the multi-tasking machines, the shop relied on single-process turning machines and six-pallet horizontal machining centers with 120-tool magazines. This manufacturing strategy, unfortunately, resulted in time-wasting bottlenecks as the parts moved between each single-process machine. According to Tremain, the shop would have three or four containers worth of material just sitting in limbo between turning and milling operations.

Now, MTH Tool’s multi-tasking machine list has grown to include 12 INTEGREX Multi-Tasking Machines and a turning machine with multi-tasking capability, all of which are from Mazak. Each of the shop’s Mazak INTEGREX Multi-Tasking Machines utilize gantry-type loaders, a 110 or 120-tool storage magazine and 1,000-psi high-pressure coolant capability, along with tool eye and part inspection probes. These are the features and capabilities that Tremain said are critical to the shop’s continuous and unattended operation, fast job setups and short machine changeover times.

The Mazak turning machine is a QUICK TURN SMART NEXUS 250MSY with milling capability, second spindle and Y axis, while most of the INTEGREX machines are i-100ST, i-200ST or i-300ST models. In addition to a main turning spindle and tilt milling spindle, the INTEGREX i Series machines can feature a second turning spindle (S) and a lower tool turret (T) with optional live tools.

Thanks to multi-tasking machine technology, MTH Tool rarely has any WIP like it did with the horizontals. This is because the multi-tasking machines give the shop single-setup, DONE-IN-ONE part processing, meaning raw parts load into a Mazak Multi-Tasking Machine and exit it complete.

DONE-IN-ONE capability is also what has allowed the shop to increase output with fewer machines and less required manpower. Fewer machines, in turn, has boosted cost-effectiveness and helped conserve valuable shop floor space. And because multi-tasking machines eliminate the need for any in-process work handling, MTH Tool has experienced incredible improvements in its processing consistency and flexibility as well as in part concentricity and overall accuracy.

According to Tremain, the shop’s facility would need to be twice its current size if it had continued with its previous production strategy and the single-process turning and milling machines. “We could not have grown to our current level of sales and production capacity/output without the multi-tasking INTEGREX machines,” he said. “With our old strategy, the output we now accomplish with our 12 Mazaks would have required over 30 individual single-process machines and the hard to find machinists to run them.”

Indeed, when it comes to improved part accuracy and concentricity, there are some instances in which the shop has experienced five-fold improvements. Concentricity between pump components is critical because all of the parts mount to each other or are stacked together; the more precise each individual component is, the better the overall pump and its performance.

As a selling point for MTH Tool’s customers, the flexibility of its Mazak Multi-Tasking Machines allows the shop to produce any one of its parts on multiple INTEGREX machines. When large customers visit a small shop such as MTH Tool, risk management is always a hot topic, but these customers soon realize that even if one machine is down, they can still get their parts when needed – when each machine can accomplish every process, there is always a backup.

“When a half-billion-dollar company walks in to your shop intending to have you produce parts for them, they want to know that glitches in your operations will not bring their production lines to a screeching halt,” explained Tremain.

Multi-tasking coupled with automation further intensifies MTH Tool’s output and production agility. When part demand fluctuates, the INTEGREX machines allow the shop to easily and quickly switch over from one part to another.

“These machines, in my opinion, are made for high-mix, low-volume environments, mainly because the setup times are relatively short” commented Tremain. “This is due to the fact that we use customized chuck jaws and gantry robot grippers and plates that accommodate multiple part sizes and types. Tools don’t have to change because we load each machine with all the tools it needs to run all the jobs assigned to it. It’s also way less expensive to cut a set of chuck jaws than it is to make a tombstone for a horizontal machining center.”

In terms of job lot sizes, the shop tends to issue work orders per a machine’s automation loading table size. Depending on the machine, those capacities can vary from multiples of 48 pieces to multiples of 36, with the median job run size at around 72 pieces.

In many cases, the shop achieves 24 hours of continuous production from its INTEGREX Multi-Tasking Machines, some of which have stacker style gantries that accommodate up to 320 of the shop’s pump components at one time. Machinists will start the machines early afternoon on a Friday, and they will run unattended all through the weekend and into Monday before stopping.

To keep tabs on unattended operations, the shop’s machinists use internet-based software together with the MTConnect communication protocol to remotely access, monitor and record machine status. The shop has been using MTConnect for over two years and incorporated it in part because its Mazak machines allowed the shop to do so quite easily.

According to Tremain, the first thing the shop wanted to figure out was its machine utilization. “When we calculate utilization, we include all the times that most shops will remove, such as time for lunch or employee vacations,” he explained. “Our 100 percent utilization is 24/7, 365 days a year. Even though we may not actually run at that, we use it as our basis. With that said, for our parts and materials, 33 percent or so across all machines is good. If others without multi-tasking machines measured to our basis, my guess is that their percentages would probably be a good 10 percent less than ours.”

The shop also learned, using MTConnect, what part cycle times really are and that it could actually visualize a part’s history – what its cycle time was two years ago and what it is now. For example, when the shop incorporated a simultaneous machining strategy on its INTEGREX machines, MTConnect indicated that the cycle times had actually increased on some parts. The shop used the data to determine which part programs needed to have additional optimization, which significantly reduced the cycle times.

Tremain’s father Dave Tremain started MTH Tool in 1965 in a garage. The shop specializes in regenerative turbine style pumps first developed in the 1920s primarily for feeding hot water boiler systems. What makes the pumps special is that in a compact package, they generate medium-high pressures but at relatively low flow rates, which is ideal for overcoming the pressure of a boiler system to continuously feed water into it. The shop also produces some associated pump accessories.

On average, each pump requires five or so machined components that primarily include motor brackets, impellers and covers. Additionally, pumps are available in multiple-stage versions that, with every additional stage, generate higher pressures.

Pump part and component tolerances are often 0.0005”, and according to Tremain, they strive to get even tighter. Customers demand higher pressure pumps that, in turn, require better leak control through tighter, more precise fits between parts.

Workpiece materials are usually cast iron, bronze and 316 stainless steel, with sizes ranging from 2.5” diameters up to around 14”. Most parts require face turning that the shop does using mill-turn operations on its Mazak Multi-Tasking Machines. According to Tremain, doing so is not only faster, but the milling tools last significantly longer than the single-point inserts that would ordinarily be used for turning. “With automation, we quickly found out that the cost of perishable tooling just doesn’t matter anymore. The only thing that counts is keeping the machine running as long as possible, unattended,” he said.

A healthy 70 percent of MTH Tool’s business is from OEMs, especially those in the temperature control/chiller market. The use of chillers continues to grow, especially for maintaining critical operational temperatures in electronics and the heads on laser and plasma cutting machines, as well as for other systems such as MRI machines and radar units. The remaining 30 percent of pumps are sold through distribution and can make their way into a myriad of applications ranging from aerial forest-fire-fighting equipment to oil and gas applications.

“We’re not a job shop, and last year we generated about 140,000 machined parts,” said Tremain. “About seven years prior to that, our production was only 70,000, and that increased output correlates directly with our switch from single-task/process machines to multi-tasking INTEGREX technology. To this day, we continue to review, reengineer and improve upon our existing designs, as well as develop completely new pumps, but the one constant is that we will produce components for them using our Mazak Multi-Tasking INTEGREX Machines.

SOURCE: Mazak Corporation