YATO Machine Combined Machine Tool Solutions for Precision Valve Processing

Why have Combined Machine Tools become the production method of choice for many modern valve manufacturers?

By 2026, valve manufacturers will be living and working in a very different world from that which they knew only a few years before! Labor cost increases, increasing machining tolerances, and customer requirement to shorten manufacturing times and produce high volumes of custom valves are challenges faced by industry worldwide.

For brass ball valves, plumbing valves, water control valves, industrial valves, and fluid control components, the traditional way to process parts – moving through standalone machines – is gradually giving way in practical production environments to Combined Machine Tool systems.

In an ideal practical situation, the properly designed Combined Machine Tool gives greater throughput, and manufacturer/operator return for capital investment, than a gaggle of independent CNC machines.

Manufacturers producing high volumes of brass valve bodies have found in practice that the bottleneck at the job is rarely the speed of the spindle. Instead the situation is often congested by the part-feeding, repositioning, fixture change, and errors which accumulate between positioning for different operations.

Modern Valve Machining Machines, Rotary Transfer Machines, Multi-Station Machine Tools, and Dedicated Machining Machines enjoy practical measurable advantages for this reason.

What is a Combined Machine Tool (CMT)?

Combined Machine Tools are those systems which “combine” more than one machining operation in a single production platform.

Typical included operations are;

• Drilling
• Tapping
• Milling
• Boring
• Reaming
• Facing
• Thread machining
• Cross-hole machining
• Others including computer manipulated or computer control of special machining operations

Why transport the valve “through” several machines correctly processing the part when it only has to move ever so slightly through its CMT?

Common Machine Configurations

Usually found in contoured work are:

Servo Rotary Table

In this device, a precision angle of travel and high-accuracy end-of-travel position ensure that parts are correctly indexed to and from work stations.

Typical index-from-to accuracy is:

±5 to ±15 arc-seconds

This eliminates much of the error accumulation encountered with multistation machining on automatically controlled machines.

Multi-Spindle Head

Also available as the Multi-Spindle Drill Head, this machine permits several holes to be machined simultaneously.

For processing a valve body, four, six, or even eight holes can be machined in a single operating cycle.

This applies to higher production runs. A standard part might use only half these heads.

CNC Rotary Table

A more modern method is with the CNC type of rotary table that permits programming to do similar types of valve body machining on any type size, style, or model without extensive mechanical changes.

Multi-Axis Machining Unit

Another step in this evolution is the design of a Multi-Axis Machining Unit that permits machining from several directions in a single operative cycle, thus reducing the amount of machining required in the setup.

WhyIndependent CNC Machines Do Not Produce More than Expected

Many naive owners of new plants accept the idea that more CNC machining centers mean more of these machines contribute directly to increased production.

Usually wrong!

Actual data may be different.

Consider the production of a brass valve body:

• Face machined
• Drill main passage
• Drill sides
• Tap threads
• Bore in seats
• Deburr

Traditional production route might be this:

Though spindle use efficiency may be not too low, actual production time may be short because of:

• Time for loading
• Changing fixtures
• Movement of parts to and from part to be processed
• Inspection for quality mode between multiple operations
• Need to check positioning

In many factories, the time of the lathe spindle is only about 40 per cent of total cycle time.

The other 60 per cent does not produce.

An adequately engineered type of Transfer Machine often reduces the total time required by 35 to 65 per cent, besides improving dimensional correctness.

The Hidden Accuracy Problem in Valve Body Processing

Valve manufacturers too often think in terms of machining tolerance.

Process engineers think of datum transfer.

And they’re not the same thing.

A valve body can meet all individual feature tolerances and still create an assembly problem if every operation is based on a different locating surface, such as;

• main bore concentricity
• stem hole alignment
• thread centerline
• position of seat geometry

One Valve Body Machining Machine using a unified fixture strategy minimizes these kind of datum stack-up errors far more than making the machine corners from 0.01mm to 0.005mm.

Combined Machine Tool Architectures Used in Valve Production

Rotary Transfer Machine

These machines index workpieces around a circular or curved machining platform.

Best suited for:

• Brass ball valves
• Water valves
• Plumbing fittings
• High volume valve bodies

Typical production range:

3,000 to 20,000 pieces/day

Advantages:

• compact footprint
• high productivity
• stable cycle time

Limitations:

• Less adaptable to non-quite-variable product families
• Requires dedicated tooling design

Linear Transfer Machine

Transfer Machine with linear indexing allows larger components to be processed, and more concentrated stations.

Best for:

• Industrial valves
• Large valve bodies
• Customized valve components

Benefits:

• Greater flexibility
• Larger work envelope

Drawbacks:

• Larger floor space requirement

Multi-Station Machine Tool

A Multi-Station Machine Tool is composed of several at least partly dedicated machining units surrounding a centralized workpiece handling system.

Best suited for:

• Medium-to-high production volume
• Multiple valve variants
• Flexible manufacturing environments

Where CNC Machining Centers Still Make More Sense

Transfer machines are automatically assumed as superior alternatives.

That is rarely the case.

For annual production of less than around 50,000 pieces per valve model, stand alone CNCMachining Machines often exceed the economic performance of dedicated transfer machines.

Typical situations are:

• Frequent design revisions
• Prototype valve development
• Small batch production
• Custom industrial valves

The flexibility of CNC machining centers offsets their lack of speed compared to dedicated transfer systems.

This in part is the reason many of the world’s successful valve factories utilize both types of machine.

They utilize:

• CNC production cells for development and low volume orders
• Combined machine tools for mass production

Valve Types That Benefit Most from Combined Machining Systems

Brass Ball Valve Bodies

A Brass Valve Machining Machine can combine:

• Through-hole drilling
• Side-port drilling
• Stem hole machining
• Thread tapping

within a single automated cycle.

Water Valve Components

A Water Valve Manufacturing Machine minimizes the variation in part diameter attributable to multiple sealing surfaces and threaded connections.

Plumbing Fittings

A Plumbing Fittings Machine utilizes simultaneous multi-spindle processing because most of the part features are repetitive and geometrically standardized.

Brass Plumbing Hardware

A Brass Components Manufacturing Machine boosts throughput by requiring fewer touches from your operators.

Later in 2026

Digital Twin Assisted Process Optimization

Machine builders are taking to simulating:

• cutting forces
• tool wear
• fixture deformation
• thermal expansion

Analyzing these variables, and more, before the physical machine is cut helps reduce commissioning time significantly.

Servo-Driven Adaptive Machining Units

New machining units adaptively adjusting feed rates on the fly based on data from spindle loads.

Benefits:

• longer tool life
• increased consistency
• reduced operator interaction
• integrated machine vision

Machine Vision

Machine vision systems now inspect:

• thread quality
• hole presence
• surface defects
• consistency of dimensions

while parts are made, not post-production.

Predictive Maintenance Systems

Advanced Valve Production Equipment increasingly integrates:

• vibration monitoring
• thermal monitoring
• lubrication diagnostics
• tool life prediction

to improve uptime and reduce unplanned downtime.

Choosing the Right Valve Manufacturing Solution

What Determines Success More Than Machine Selection

In years of working on valve manufacturing projects, one constant rings true of our friends in the factories:

Factories take months spec’ing spindle brands, servo systems, CNC controllers, etc… and ignore fixture engineering.

In most cases in valve production, fixture strategy has more impact on productivity and quality than the difference between two premium CNC platforms.

A properly engineered Valve Manufacturing Solution takes into consideration the following before spindles and controller brands:

• datum strategy
• tool access
• chip clearance
• automation compatibility
• product growth

The manufacturers that historically realized the lowest cost per valve achieved that by eliminating steps in handling, reducing need for things like changeovers, and keeping logically connected geometric relationships in mind for all operations right through the machining processes.

It’s interesting, seeing aftermarket retrofit trends for today’s brass valve producers.

Most competitive factories making brass valves today number in the 10 to 15 percent range and these days, they’ve stopped buying machines. Instead, they are investing in complete machining systems where the machine, tooling, automation, fixture design, and process engineering are a complete and integrated manufacturing platform.