16—GEAR Production Supplement

F E A T U R E By Carl Olsen | Software Engineering Manager | Omax Corp.

Manufacturing Gears with Waterjet MachiningAdvances in abrasive waterjet technology provide gear manufacturers with a fast and accurate method for cutting a variety of gear geometries and materials.

Job shops typically don’t think

of abrasive waterjet machining

as a gearmaking process.

But these machines can cut nearly

any 2D or 3D shape—including

gear teeth—from any material of

any thickness, faster, easier and

more cost effectively than many

conventional techniques.

Abrasive waterjet machining has

been around for decades. It involves

forcing a high-pressure stream of

water with an abrasive such as

garnet through a small nozzle orifce

to cut materials. Early systems

were often inaccurate and diffcult

to control, but in the early 1990s

the tide for this type of machining

turned. Abrasive waterjet machine

manufacturers developed new

technology that harnessed control

of the cutting nozzle via advanced

PC controller software, making

the waterjet cutting process more

practical, affordable and simple

to use.

Fast-forward to current abrasive

waterjet technology which, through a combination

of modern hardware and software, offers

substantial versatility along with impressive

cutting speeds and tolerances. In fact, within

the past fve years alone, the technology has

experienced signifcant improvements, including

faster speeds, better edge quality and tighter

tolerances than the industry once thought

possible using this method.

Ideal ApplicationsIn terms of gear production, abrasive waterjet

machines are typically at their best when

prototyping or handling small to medium

production runs. This makes the machines

perfect for job shops that produce gears on an

Abrasive waterjet machining provides versatility in cutting

different materials, such as this 6.25-inch thick nylon gear.

March 2015—17

intermittent basis.

Gear production on an abrasive waterjet

machine can range from mere minutes (for

example, a miniature planetary gear) to several

hours (such as in the repair of a 4-inch-thick wind

turbine gear), depending on the thickness of the

workpiece material and the total linear perimeter

of the cutting area.

Common gear geometry types that shops

can cut on abrasive waterjet machines include

standard, planetary, bevel, square and helical,

made from various workpiece materials such as

steels of different hardness levels and carbon

fber-reinforced plastics. Racks and sprockets

are also made using abrasive waterjet machines.

Shops can cut all of these gear shapes on the

same machine with minimal—if any—setup,

fxturing or tool changes between parts.

Abrasive waterjet machines also allow for

the creation of nonstandard gear geometries.

Oftentimes, shops base the gear tooth profle

on the actual manufacturing method that they

will use to generate the teeth. If a tooth profle

can be generated with a thin cylindrical stream,

a gear can be quickly manufactured, which

opens up new opportunities for gear designers.

This is particularly true during the research

and development and prototype stages, where

multiple gear iterations are required to determine

the geometry that offers the best balance of cost

and turnaround time.

When it comes to gear applications that

require tight tolerances and good

surface fnish, a shop must be able

to tilt a machine’s cutting head to

compensate for the natural taper of

the jet. As a result, abrasive waterjet

machine manufacturers offer special

tilting-head accessories that enable

shops to achieve near-zero taper in

their fnished gears.

An abrasive waterjet machine’s

nozzle type, abrasive type and size,

and cutting speed also contribute to

the level of surface fnish a shop can achieve in

gear production. Slow cutting speeds usually

provide a reasonably good surface fnish,

but factor in a small cutting nozzle with a fne

abrasive, and the fnish is further improved.

In most cases, it is reasonably easy for

abrasive waterjet machines to achieve tolerances

of ±0.003 inch (0.075 mm). Shops producing

small gears from thin materials have also been

known to achieve tolerances as tight as ±0.001

inch (0.025 mm) or better.

For production of high-precision gears,

shops can use the abrasive waterjet to perform

high-speed rough cutting operations to

create near-net shapes that are within a few

thousandths of an inch of the fnal surface profle.

A secondary process could then be used to

trim or polish the surface fnish to the required

specifcations.

Also highly benefcial is the fact that abrasive

Miniature planetary gears can be cut quickly with

an abrasive waterjet.

Gear geometries such as these racks can be machined in

segments with tight tolerances for assembly.

18—GEAR Production Supplement

F E A T U R E

waterjet machining is a “cold cutting” process

that keeps workpieces from experiencing the

mechanical and thermal stresses that often occur

with conventional techniques, thereby eliminating

any secondary stress-relieving processes.

In addition to new gear production, abrasive

waterjet machines can be used in gear repair

operations to avoid the cost of producing a

completely new gear. This repair capability is

especially benefcial when it comes to giant

industrial gears. With an abrasive waterjet

machine, shops can cut away old or damaged

gear teeth and cut special ftting joints that allow

the new replacement teeth—also made on the

same waterjet machine—to simply “click” into

place with minimal or no welding.

When not in gear manufacturing or repair

mode, shops don’t have to worry about an

abrasive waterjet machine sitting idle. Unlike

conventional machining techniques, the high

level of versatility that comes with an abrasive

waterjet machine makes it possible to cut

an automotive part out of steel, then easily

transition to processing titanium for an aerospace

component, for example.

Equipment HardwareWhen it comes to selecting the right abrasive

waterjet machine for gearmaking operations, it

is important to note that such equipment ranges

from very high-power machines with large

nozzles for sizeable kerf widths to lower-power

machines with miniature nozzles for cutting

intricate part geometries.

A typical waterjet cutting nozzle cuts a kerf

width of approximately 0.030 inch (0.75 mm).

When cutting thick materials, however, a 0.042-

inch (1-mm) or 0.048-inch (1.2-mm) nozzle

might be used to generate a wider kerf. For

tiny, complex work, there are some nozzles that

produce much smaller kerfs.

The type of pump used with an abrasive

waterjet machine determines the level of

effciency shops can achieve in gear production.

A direct-drive pump, which uses a crankshaft

to move the plungers that pressurize the water,

is much more effcient than an intensifer

pump, which relies on power-consuming

hydraulics.

Through this increased effciency, direct-

drive pumps such as those used on Omax

machines deliver more horsepower at the

cutting nozzle than intensifer designs

at any pump power rating, regardless of

pressure. As with all cutting processes,

material removal rates are a function of

the power put into the cutting surface.

Overall, direct-drive pumps create a more

Complex nonstandard gear geometries are simple to cut with

an abrasive waterjet.

Gear repair is often more cost effective with abrasive

waterjet, such as with this 4-inch-thick wind turbine

gear that is over 5 ft. in diameter.

March 2015—19

Omax Corp., call 253-872-2300 or visit omax.com.

powerful abrasive stream than intensifer pumps,

resulting in faster gear cutting speeds and

increased productivity.

System SoftwareSoftware also plays a major role in abrasive

waterjet machining of gears. Although CAD

software generates the gear geometries, it is

the software the machine’s controller uses that

optimizes the tool path and puts the gear cutting

into motion. To further simplify the process,

some manufacturers offer special gear shape

generation software unique to their equipment.

Controlling the machine’s abrasive waterjet

to achieve the best balance of speed and

precision in gear production can sometimes

be diffcult. However, many abrasive waterjet

machine manufacturers simplify the process via

intuitive control software packages that enable

the machine to automatically manage the jet in

a manner that is fast, effcient and transparent to

the operator.

For instance, Omax’s control software

features built-in cutting models that an

operator can use to quickly input the part

geometry, desired surface fnish quality and

any attached equipment such as nozzles,

pumps and accessories. From this data, the

control can predict the jet cutting behaviors and

automatically compensate for them.

Two of the many jet behaviors this control can

predict and compensate for are jet lag (where

the bottom of the cut lags behind the top) and

taper (where either the top or bottom of the cut

is wider than the rest). A combination of slowing

the jet down and tilting the cutting head into

the direction of the cut helps balance the jet

lag, while simply tilting the cutting head into the

direction of the cut offsets the unwanted taper.

Omax recently released its fourth generation

built-in cutting model that not only optimizes tool

paths automatically, but also gives operators

precise predictability as to the cutting speeds,

taper, jet lag and other factors of those particular

tool paths. And through this update, the company

has proven to be able to cut a 10-inch (254-mm)

gear in half the time it was able to previously.

Versatile InvestmentBecause of their speed, precision, versatility

and cost-saving capabilities, abrasive waterjet

machines can be a sound capital investment for

shops that handle gear prototyping or small-to-

medium gear production runs. In fact, this form

of machining has signifcantly evolved over the

past few years, so much so that it is quickly

transitioning away from being an alternative

process to one that equals or surpasses many

other cutting methods.

Using the proper abrasive waterjet hardware can increase

production, tolerances and overall gear quality.

Advanced software tools reduce programming needs and

maximize the process of generating gear toolpaths.

20—GEAR Production Supplement

P R O D U C T N E W S Edited by Stephanie Monsanty | smonsanty@mmsonline.com

Non-Contact Probe Enables Force-Free Measurement of Gear Profles

Hexagon Metrology’s HP-O non-contact scanning

probe is intended to be an alternative to tactile analog

measurement and scanning probes and is well-suited

for scanning large parts and those that are rotationally

symmetric. The device exerts no physical impact on the

workpiece for force-free measurement of blisks, blades,

gear profles, fank lines and other potentially deformable

parts without a loss of accuracy. Its 3-mm diameter and

measurement range of 20 mm provides access to points

that are not accessible to tactile probes, the company

says, and optical measurements can be captured in

single-point or scanning mode.

According to Hexagon, the probe delivers repeatability

of less than 0.3 microns when used with its Leitz PMM-C

CMM. Offering an acceptance angle of ±30 degrees,

the probe can measure diffcult-to-access features at

a scanning speed of 1,000 points per second for rapid

throughput. Additionally, the probe’s scanning technology

is based on frequency-modulated interferometric optical

distance measurement and is not affected by ambient

light. It is multi-sensor compatible in a single part

program using a standard toolchanger.

Hexagon Metrology Inc. | 855-443-9638 |

hexagonmetrology.us

Software Eases Milling of Gears, Splines

Sandvik Coromant’s InvoMilling 1.0 software enables

fexible manufacturing of gears and splines on universal

fve-axis machining centers. Developed by Sandvik

Coromant and Euklid, the CAM software generates

CNC programs to produce different gear profles with

a limited range of standard-stock precision tools. The

software includes milling path generation and simulation

functionality. According to Sandvik Coromant, when

combined with its CoroMill 161 and 162 cutters, the

InvoMilling software enables shorter lead times for

production of gears and splines. The method is suitable

for machining small- and medium-size batches.

Sandvik Coromant Co. | 800-726-3845 |

sandvik.coromant.com/us

March 2015—21

305-691-6300

800-248-5152

www.southerngear.net

sales@southerngear.net

At Southern Gear & Machine, your parts are in the skilled hands of our machinists and engineers who have an average of 25 years of experience in gear manufacturing.

When you place your order with Southern Gear, you can rest assured that experienced engineers and machinists are creating your part, at our facility, under our quality control, and with our outstanding customer service.

Can your current gear manufacturer make these same guarantees?

Our machinists and engineers have an •

average of 25 years experience in gear manufacturing.

Our employees have been with our •

company an average of 13 years.

We have more the 50 gear cutting •

machines alone.

We outsource only plating, heat treating •

and NDT.

We have been manufacturing precision •

gears for 58 years.

We have invested close to one million •

dollars in equipment each year for the past fi ve years.

Multitasking CNC Lathes Minimize

Noncutting Time

Okuma’s Multus U-series multitasking CNC lathes

are capable of gear machining, skiving and hobbing

operations. Designed to reduce setup time, improve

accuracy and minimize noncutting time, the lathes feature

a heavy-duty construction for long-term rigidity and

accuracy. They are said to be well-suited for machining

process-intensive parts, including applications within

the aerospace, automotive, oil and energy, medical, and

construction industries. Two machine sizes are available:

The Multus U3000 offers a maximum diameter of 25.6"

and bed length of 39.4", while the Multus U4000 offers a

maximum diameter of 27.55" and bed length of 59.05".

The series is capable of fexible CNC machining from

all directions with a rigid traveling column that enables

cutting along the entire Y axis. The lathes are equipped

with Okuma’s thermo-friendly concept to enable stable

machining accuracy with structural design and thermal

deformation control. The design enables easy tool loading

from the machine front, improved spindle access for

faster setup times and smooth chip discharge for better

fows, the company says. The THINC OSP-P300S control

is said to reduce keyboard operations and maximize

uptime with its collision avoidance system. The series

also can be equipped with Okuma’s Machining Navi for

maximizing tool performance by selecting optimal speeds

to avoid chatter. Extended specifcations, including 17

variations with multiple bed lengths, an optional W

subspindle and optional lower turret, enable a range

of applications.

Okuma America Corp. |

704-588-7000 | okuma.com

22—GEAR Production Supplement

P R O D U C T N E W S

Turning Center Capable of Gear Cutting,

Milling and Drilling

Emco Maier’s Hyperturn 65 Powermill offers a spindle

clearance of 1,300 mm along with a counter spindle

to enable four-axis machining and a B axis with direct

drive for fve-axis simultaneous milling operations. An

additional Y axis for the lower turret further enables

machining of complex parts. Turning, drilling, milling and

gear cutting operations are completed in a single setup

on the machine, eliminating additional handling and part

storage and improving workpiece precision. In addition,

production time, fxturing and personnel costs, and foor-

space requirements can be reduced. According to the

company, the machine is well-suited to serial production

of workpieces for the automotive, material handling and

aircraft industries.

The 29-kW milling spindle offers 79 Nm of torque with

speeds ranging to 12,000 rpm. The B-axis direct drive

provides contour capabilities with fve-axis simultaneous

machining as well as shorter tool-change times. The 29-

kW counter spindle provides 250 Nm of torque, enabling

machining a workpiece with two tools simultaneously

for four-axis machining. The lower turret with integrated

milling drive can also be used for complex milling

operations in all 12 positions, combined with the Y axis

and ±50-mm travel.

The HSK-T63 tool interface can be used for both

turning and drilling/milling work. It can be continuously

swiveled within a range of ±120 degrees and clamped

at any point. With a useful Y travel of +120/-100 mm,

the spindle is capable of gear cutting operations as well

as turning and milling work for crankpins, fve-axis

machining, and more. The machine can be equipped

with a 20-station pickup tool magazine, or a 40- or

80-station chain magazine. The machine is controlled by

a Siemens Sinumerik 840D-sl. Emco CPS Pilot simulation

software enables planning, programming, simulating and

optimizing production runs using a 3D model of

the machine.

Emco Maier Corp. | 248-313-2700 |

emco-world.us/en

Dry-Cut Hobbing Machine for Small-Diameter Gears

An addition to its GE series of dry-cut hobbing machines,

Mitsubishi Heavy Industries’ GE 10A is suitable for mass

production of small-diameter gears such as those used

in vehicle automatic transmission systems. Capable of

accommodating gears ranging to 100 mm in diameter,

the hobbing machine offers radial and axial travel speeds

of 20,000 mm/min. with direct-drive motors in the main

spindle and table. The cutting length of the hob measures

300 mm for greater machining effciency, and maximum

hob rotation speed is 3,500 rpm.

Use of a high-speed loader is said to reduce workpiece

changing time to 2 sec. According to the company, the

machine’s structure enables simple setup changes without

the use of tools. Cooling mechanisms incorporated

into the main spindle and table enable high machining

precision by guarding against thermal displacement. The

machine can be used with Siemens or FANUC CNC

control units.

Mitsubishi Heavy Industries - Gear Cutting | 248-

668-4143 | mitsubishigearcenter.com

March 2015—23

Gear Inspection System Features Active Air Suspension

Available from Kapp Technologies, the R&P Metrology

RPG 3500DS gear inspection system is capable of

measuring parts ranging to 3,500 mm OD or, optionally,

4,000 mm OD. The system is suitable for checking spur

and helical gears, pinion shafts and double helical gears,

bevel gears, hypoid gears, worms, worm wheels, and

cutting tools.

The four-axis (+1) generative gear inspection system

features an active air suspension system and does not

require a special foundation. Constructed with dark granite

for temperature stability, the system offers enhanced

inspection accuracy and repeatability. It is equipped

with air bearings, linear motors, a direct-drive hydrostatic

rotary table, a touchscreen and RP Utilities software.

Optional CMM software can be installed to enable

virtually all types of 3D CMM measurements, the

company says.

Kapp Technologies | 303-447-1130 | kapp-niles.com

24—GEAR Production Supplement

P R O D U C T N E W SP R O D U C T N E W S

Handling all your grinding needs...the Smallest and the Largest.

KAPP Technologies2870 Wilderness Place Boulder, CO 80301Phone: (303) 447-1130 Fax: (303) 447-1131 www.kapp-niles.com info-usa@kapp-niles.com

GENERATING Grinding 8mm - 1,250mm PROFILE Grinding 8mm - 8,000mm

Analytic Inspection System for Gears and Gear Cutting Tools

Gleason’s 175GMS analytical gear inspection system

offers complete inspection of automotive, aerospace and

other smaller gears, as well as gear cutting tools and

non-gear parts. A Renishaw 3D scanning probe head

provides accuracy and fexibility for inspecting gears and

gear-cutting tools, particularly fner-pitch gears. The system

includes surface fnish measurement and prismatic feature

measurement.

The 175GMS system features the Windows 7-based

Gleason GAMA 3.0 applications software suite. The user

interface offers simple input screens for programming

workpieces and cutting tool data, and built-in tutorial

information for gear features with text, pictures and video

that can be edited by the user. The remote control I/O

system improves movement optimization and reduces

cycle times for inspecting virtually any gear or gear tool.

The system’s workstation can be optionally equipped

with an advanced operator interface that features an

environmental monitoring station for recording temperature

and humidity; video, note pad and voicemail messaging;

and Gleason Connect for enhanced remote diagnostic

support, creation of work instructions, online training tools,

multilingual communication and more.

Gleason Corp. | 585-473-1000 | gleason.com