The document discusses various types of lathes and machining processes. It describes CNC lathes, big bore lathes, and PVC pipe threading machines. It explains that CNC lathes provide power assisted movement of the carriage compared to manual lathes. The document also discusses gear hobbing machines, polygon turning machines, and CNC retrofitting of older machines.

1. CNC big bore lathe and PVC pipe threading machine
In its simplest form the carriage holds the tool bit and moves it longitudinally (turning) or
perpendicularly (facing) under the control of the operator. The operator moves the carriage manually
via the handwheel (5a) or automatically by engaging the feed shaft with the carriage feed
mechanism (5c).
CNC big bore lathe provides some relief for the operator as the movement of the carriage becomes
power assisted. The handwheels (2a, 3b, 5a) on the carriage and its related slides are usually
calibrated, both for ease of use and to assist in making reproducible cuts. Calibration marks will
measure either the distance from center (radius), or the work piece's diameter, so for example, on a
diameter machine where calibration marks are in thousandths of an inch, the radial handwheel dial
will read .0005 inches of radius per division, or .001 inches of diameter. The carriage typically
comprises a top casting, known as the saddle, and a side casting, known as the apron
A secondary operation' is a machining operation requiring a partially completed part to be secured in
a second machine to complete the manufacturing process. Generally, advanced CAD/CAM software
uses live tools in addition to the main spindles so that most parts that can be drawn by a CAD
system can actually be manufactured by the machines that the CAD/CAM software support.
Carbides pvc pipe threading machine tolerate much higher machining speeds without wearing.
This has led to machining times shortening, and therefore production growing. The demand for
faster and more powerful lathes controlled the direction of lathe development.
A metal lathe or metalworking lathe is a large class of lathes designed for
precisely machining relatively hard materials. They were originally designed to machine metals;
however, with the advent of plastics and other materials, and with their inherent versatility, they are
used in a wide range of applications, and a broad range of materials. In machining jargon, where the
larger context is already understood, they are usually simply calledlathes, or else referred to by
more-specific subtype names (toolroom lathe, turret lathe, etc.). Pvc pipe threading
machine remove material from a rotatingworkpiece via the (typically linear) movements of various
cutting tools, such as tool bits and drill bits.
The availability of inexpensive electronics has again changed the way speed control may be applied
by allowing continuously variable motor speed from the maximum down to almost zero RPM. This
had been tried in the late 19th century but was not found satisfactory at the time. Subsequent
improvements in electric circuitry have made it viable again.
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2. CNC Lathe Manufacturers
A lathe is a machine tool used principally for shaping pieces of metal, wood, or other materials by
causing the workpiece to be held and rotated by the lathe while a tool bit is advanced into the work
causing the cutting action. Lathes can be divided into three types for easy identification: engine
lathe, turret lathe, and special purpose lathes. Some smaller ones are bench mounted and semi-
portable. The larger lathes are floor mounted and may require special transportation if they must be
moved. Field and maintenance shops generally use a lathe that can be adapted to many operations
and that is not too large to be moved from one work site to another. The engine lathe is ideally suited
for this purpose. A trained operator can accomplish more machining jobs with the engine lathe than
with any other machine tool. Turret lathes and special purpose lathes are usually used in production
or job shops for mass production or specialized parts, while basic engine lathes are usually used for
any type of lathe work.
Additionally, as many Swiss lathes incorporate a secondary spindle, or 'sub-spindle', they also
incorporate 'cnc lathe manufacturers'. Live tools are rotary cutting tools that are powered by a
small motor independently of the spindle motor(s). Live tools increase the intricacy of components
that can be manufactured by the Swiss lathe. For instance, automatically producing a part with a
hole drilled perpendicular to the main axis (the axis of rotation of the spindles) is very economical

3. with live tooling, and similarly uneconomical if done as a secondary operation after machining by the
Swiss lathe is complete. A 'secondary operation' is a machining operation requiring a partially
completed part to be secured in a second machine to complete the manufacturing process.
Generally, advanced CAD/CAM software uses live tools in addition to the main spindles so that most
parts that can be drawn by a CAD system can actually be manufactured by the machines that the
CAD/CAM software support.
When turning, a piece of relatively rigid material (such as wood, metal, plastic, or stone) is rotated
and a cutting tool is traversed along 1, 2, or 3 axes of motion to produce precise diameters and
depths. Turning can be either on the outside of the cylinder or on the inside (also known as boring)
to produce tubular components to various geometries. Although now quite rare, early lathes could
even be used to produce complex geometric figures, even the platonic solids; although since the
advent of CNC it has become unusual to use non-computerized toolpath control for this purpose.
Hard turning is a turning done on materials with cnc lathe manufacturers a Rockwell C hardness
greater than 45. It is typically performed after the workpiece is heat treated.[3]
The process is intended to replace or limit traditional grinding operations. Hard turning, when applied
for purely stock removal purposes, competes favorably with rough grinding. However, when it is
applied for finishing where form and dimension are critical, grinding is superior. Grinding produces
higher dimensional accuracy of roundness and cylindricity. In addition, polished surface finishes of
Rz=0.3-0.8z cannot be achieved with hard turning alone. Hard turning is appropriate for parts
requiring roundness accuracy of 0.5-12 micrometres, and/or surface roughness of Rz 0.8–7.0
micrometres. It is used for gears, injection pump components, hydraulic components, among other
applications.[3]
Turning can be done manually, in a traditional form of lathe, which frequently requires continuous
supervision by the operator, or by using an automated lathe which does not. Today the most
common type of such automation is computer numerical control, better known as cnc lathe
manufacturers. (CNC is also commonly used with many other types of machining besides turning.)
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CNC Machine Retrofitting and CNC Retrofitting Services
Principally retrofitting describes the measures taken in the manufacturing industry to allow new or
updated parts to be fitted to old or outdated assemblies (like blades to wind turbines).
The production of retrofit parts is necessary in manufacture when the design of a large assembly is
changed or revised. If, after the changes have been implemented, a customer (with an old version of
the product) wishes to purchase a replacement part then retrofit parts and assembling techniques
will have to be used so that the revised parts will fit suitably onto the older assembly.

4. Another example of this is Cnc machine retrofitting, where older vehicles are fitted with new
technologies: power windows, cruise control, remote keyless systems, electric fuel pumps, etc.
The term is also used in the field of environmental engineering, particularly to
describe construction or renovation projects on previously built sites, to improve water quality in
nearby streams, rivers or lakes. The concept has also been applied to changing the output mix
of energy from power plants to cogeneration in urban areas with a potential for district heating.
Sites with extensive impervious surfaces (such as parking lots and rooftops) can generate high
levels of stormwater runoff during rainstorms, and this can damage nearby water bodies. These
problems can often be addressed by installing new stormwater management features on the site, a
process that practitioners refer to as stormwater retrofitting. Stormwater management practices used
in retrofit projects include rain gardens, permeable paving and green roofs.
Additionally, as many Swiss lathes incorporate a secondary spindle, or 'sub-spindle', they also
incorporate 'cnc retrofitting services'. Live tools are rotary cutting tools that are powered by a small
motor independently of the spindle motor(s). Live tools increase the intricacy of components that can
be manufactured by the Swiss lathe. For instance, automatically producing a part with a hole drilled
perpendicular to the main axis (the axis of rotation of the spindles) is very economical with live
tooling, and similarly uneconomical if done as a secondary operation after machining by the Swiss
lathe is complete. A 'secondary operation' is a machining operation requiring a partially completed
part to be secured in a second machine to complete the manufacturing process. Generally,
advanced CAD/CAM software uses live tools in addition to the main spindles so that most parts that
can be drawn by a CAD system can actually be manufactured by the machines that the CAD/CAM
software support.
When turning, a piece of relatively rigid material (such as wood, metal, plastic, or stone) is rotated
and a cutting tool is traversed along 1, 2, or 3 axes of motion to produce precise diameters and
depths. Turning can be either on the outside of the cylinder or on the inside (also known as boring)

5. to produce tubular components to various geometries. Although now quite rare, early lathes could
even be used to produce complex geometric figures, even the platonic solids; although since the
advent of CNC it has become unusual to use non-computerized toolpath control for this purpose.
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Gear Hobbing Machine and Polygon Turning Machine
Lathes are used in woodturning, metalworking, metal spinning, Thermal spraying/ parts reclamation,
and glass-working. Lathes can be used to shape pottery, the best-known design being the potter's
wheel. Most suitably equipped metalworking lathes can also be used to produce most solids of
revolution, plane surfaces and screw threads or helices. Ornamental lathes can produce three-
dimensional solids of incredible complexity. The material can be held in place by either one or
twocenters, at least one of which can be moved horizontally to accommodate varying material
lengths. Other work-holding methods include clamping the work about the axis of rotation using a
chuck or collet, or to a faceplate, using clamps or dogs.
For a gear hobbing machine which is a theoretical involute, the fundamental rack is straight-sided,
with sides inclined at the pressure angle of the tooth form, with flat top and bottom. The
necessary addendum correction to allow the use of small-numbered pinions can either be obtained
by suitable modification of this rack to a cycloidal form at the tips, or by hobbing at other than the
theoretical pitch circle diameter. Since the gear ratio between hob and blank is fixed, the resulting
gear will have the correct pitch on the pitch circle, but the tooth thickness will not be equal to the
space width.
Most hobs are single-thread hobs, but double-, and triple-thread hobs increase production rates. The
downside is that they are not as accurate as single-thread hobs.[9] Depending on type of gear teeth
to be cut, there are custom made hobs and general purpose hobs. Custom made hobs are different
from other hobs as they are suited to make gears with modified tooth profile. The tooth profile is
modified to add strength and reduce size and noise of gears.

6. In addition to the spindle and its bearings, the headstock often contains parts to convert the motor
speed into various spindle speeds. Various types of polygon turning machine
mechanism achieve this, from a cone pulley or step pulley, to a cone pulley with back gear (which is
essentially a low range, similar in net effect to the two-speed rear of a truck), to an entire gear train
similar to that of a manual-shift auto transmission. Some motors have electronic rheostat-type speed
controls, which obviates cone pulleys or gears.
In addition to the spindle and its bearings, the headstock often contains parts to convert the motor
speed into various spindle speeds. Various types ofspeed-changing mechanism achieve this, from a
cone pulley or step pulley, to a cone pulley with back gear (which is essentially a low range, similar
in net effect to the two-speed rear of a truck), to an entire gear train similar to that of a manual-shift
auto transmission. Some motors have electronic rheostat-type speed controls, which obviates cone
pulleys or gears.
Hobbing is a machining process for making gears, splines, and sprockets on a hobbing machine,
which is a special type of milling machine. gear hobbing machine or splines are progressively cut
into the workpiece by a series of cuts made by a cutting tool called a hob. Compared to other gear
forming processes it is relatively inexpensive but still quite accurate, thus it is used for a broad range
of parts and quantities.
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