The PM 750 from R&P Metrology is a portable device used to measure large parts on production machines lacking onboard inspection. A docking system with a rotary table is also available.
It’s always good to have options, and that’s what the PM line of gear inspection and measurement systems from R&P Metrology provides. Designed as a portable device, it is used to measure large parts on production machines lacking onboard inspection. It allows for inspection to be conducted on many different machines with a single measurement unit that is easy to transport between locations. In addition, a new docking station with a base plate and rotary table transforms the device into a standalone, full-featured, four-axis (+1 positioning) measurement system that is capable of profile and form measurements as well as gear inspection and 3D measurements.
The PM is a three-axis CNC measuring column, capable of gear inspection, form and profile measurements as well as 3D measurements. The system utilizes proven air bearing and linear motor technologies and industry standard 3D scanning probe systems from Renishaw. The standard models are the PM 750 and the PM 1250. The PM 1250EX (extended version) is also available for larger gears, as well as custom configurations.
R&P Metrology designs and builds its own metrology equipment concentrating on medium and large parallel axis gears, bevel gears, tools, shafts, bearing rings and 3D parts. It is represented in the United States by Kapp Technologies, which also provides support, service and sales throughout North America. Watch a video of the system in action.
Two “Baxter” collaborative robots from Rethink Robotics are helping to disrupt what third-generation shop owner Bill Marcell describes as the previous “old school mentality” of Standby Screw Machine Products, the 76-year-old contract machining business in Berea, Ohio. Today, one of the new robots does packaging, freeing an employee from this work by packing two boxes at once, while another robot loads a milling machine in an automation application likely to save the company 1,000 person-hours per year.
Collaborative robots are easily redeployable robots that work safely close to people. Mr. Marcell and project manager Jess Horvath describe their experience with the new robots in this video produced by Rethink.
Components for automotive transmissions are typically made of ductile steels such as SAE 1018, 1020 and 8620. Turning these parts is often plagued by problems with chip control, especially the tendency for these materials to produce long, stringy chips that interfere with efficient operation and/or automated production. This article from Sandvik Coromant addresses the complex variables and strategic trade-offs that must be considered in designing the most effective insert for this application. The insights into the problem and its solution will help anyone think more clearly about vexing chip control issues.
The workholding system that TRP Machine is calling the “MV16” is not actually a new product, but instead it is the way this Bohemia, New York job shop has held parts for machining for more than 20 years. Looking for a simple and inexpensive way to (A) hold several workpieces in one machining cycle, (B) hold a variety of different part numbers without setup changes, and (C) load and unload workpieces quickly from one machining cycle to the next, the shop devised a workholding system on its own able to realize those objectives. What is new now, says shop owner Roger Price, is that TRP has begun to manufacture the MV16 as a product available to other machine shops.
The system is essentially a single large plate embedded with eight independent and closely spaced double-acting vises. Each of the 16 jaw positions opens to a width of 3.25 inches, and clamps parts to a location repeatability of 0.0005 inch. Thus, 16 identical pieces can be quickly and precisely clamped for machining in the same setup, or 16 entirely different parts can be clamped into a single setup as well. Or, since the jaw positions lie in parallel, a row of four jaw positions at once can be used to clamp a workpiece up to 28 inches long.
Mr. Price says the system has been invaluable to TRP in allowing the shop to maintain high in-cut time percentages on its machining centers. The standard MV16 plate is 20.25 by 28.25 inches, but he says the system can also be customized to different sizes and even to a different number of vise positions. A tombstone version of the system uses four double-acting vises on each of four different faces to achieve a total of 32 jaw positions. Learn more from TRP Machine.
Advances in steady rest and in-process measurement technologies enable large crankshafts to be ground complete in one setup.
Junker, manufacturer of high-speed CBN grinding machines, has developed its new JuCrank series for cylindrical and non-cylindrical grinding for large crankshafts. The series offers a swing diameter of 470 mm and a part length capacity of up to 4.8 m, and can accommodate crankshafts that can weigh as much as 1,000 kg. Because these parts are so big and unwieldy, the company integrated two technologies to streamline setup and processing.
First, Junker developed its own steady rest system, believing that existing systems were too bulky and not rigid enough for high-speed grinding. These new steadies are CNC-controlled and have only one axis each, which is said to increase their stability and stiffness. A maximum of 11 steadies can be controlled individually and applied to a section at any time—even during the grinding process—to enable higher sequence flexibility.
Second, the company integrated an in-process measurement system. That’s because large crankshafts are mainly produced in small batches (in some cases as single pieces), and the forging and hardening costs are so high that scrapping a part is not an option.
To start the crankshaft grinding process, the machine’s two wheels, each mounted on a wheelhead with its own X and Z axis, pre-grind the main and pin bearings. Those diameters are measured during the process, and then the entire workpiece is measured after pre-grinding, including features such as the taper of each element, the bearing widths and lift heights.
Based on the measuring data, the machine completes the grinding process while using the WK axis whereby the grinding spindle swivels to compensate for tapers. The machine can also provide each main and pin bearing with its own profile shape with specific crowning. If necessary, the shaft ends can also be ground, which also often feature a taper. As a result, the crankshaft is ground complete in one setup.
Another application for the JuCrank machines is re-grinding of used crankshafts, whereby the crankshafts are ground based upon the measurements taken by the machine. This grinding platform also can be effective for other large-scale applications, such as printing rollers and electric motor shafts.