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Unit 8 Milling Cutters

Text I

Vocabulary Notes

  1. milling cutter (syn. cutter, mill) – фреза

milling cutter work

milling cutter design

mill operation

  1. face (syn. surface ) – поверхня, обробляти поверхню

plane surface (face)

tool surface (face)

cutter surface (face)

face cutter – циліндрова, лобова (торцева) фреза

to treat the face cutter

to depend upon the face cutter

to hold the face cutter

  1. side (milling) cutter – трибічна фреза

side (milling) cutter length

side (milling) cutter operation

side (milling) cutter design

  1. radial – фреза із звичайними загостреними зубами

radial cutter construction

radial cutter work

to fasten the radial cutter

  1. angular cutter – проста конічна (кутова) фреза

angular cutter hardness

angular cutter removal

angular cutter design

  1. end (milling) cutter – лобова (торцева) фреза

end (milling) cutter treatment

end (milling) cutter design

end (milling) cutter operation

  1. form cutter – фасонна (профільна) фреза

form cutter wear resistance

form cutter removal

form cutter construction

  1. solid cutter – суцільна фреза

solid cutter wear resistance

solid cutter treatment

solid cutter hardness

  1. inserted tooth cutter – фреза із вставними зубами

inserted tooth cutter operation

inserted tooth cutter design

inserted tooth cutter hardness

  1. shell end cutter – насадна лобова (циліндрова) фреза

to fix the shell end cutter

to treat the shell end cutter

to clamp the shell end cutter

  1. shank – хвостовик

tool shank

cutter shank

shank cutter, steam cutter – кінцева (хвостова) фреза

shank cutter wear resistance

steam cutter removal

shank cutter treatment

  1. integral – цілий, загальний

integral with the casting

integral shank

  1. arbor – облямовування

integral arbor

machine arbor

shell end cutter arbor

shank cutter arbor

  1. to mount – встановлювати, монтувати

tо mount a stem shank cutter

to mount a solid cutter

to mount a form cutter

  1. adapter – адаптер; утримувач, державка

adapter shape

adapter strength

shank cutter adapter

  1. collet – цанговий патрон, цанга

collet design

collet strength

collet removal

  1. to fit – монтувати, встановлювати

to fit on the milling machine

to fit the face cutter

to fit the spindle nose

  1. to fasten (syn. to clamp, to hold, to fix) – прикріплювати, затискати

to fasten the workpiece

to fasten the cutter

to fasten the collet

to clamp the cutting tool

to clamp the table

to hold the cutter

to fix the spindle

to fix the workpiece

  1. screw – гвинт, болт

screw size

screw application

cutter body screw

  1. tooth (мн. teeth) – зуб (зуби)

milling cutter teeth

peripheral teeth

parallel teeth

  1. straight – прямий

straight teeth

straight cutter

straight flute

  1. helical – спіральний, гвинтовий

helical teeth

helical flutes

  1. plain milling cutter – циліндрова фреза

plain milling cutter wear resistance

plain milling cutter design

plain milling cutter hardness

  1. to machine – обробляти на верстаті

to machine a surface

to machine a workpiece

  1. wide – широкий

width – ширина

wide cutter teeth

cutter width

wide face cutter

face cutter width

plain milling cutter width

Translate text I

Milling Cutters

There are many different types of milling cutters, depending upon the operations to be performed. Milling cutters are usually classified according to the work done into face, side, radial angular, end and form cutters.

They are also classified according to their construction into solid cutters, inserted tooth cutters, shell-end cutters and stem (shank) cutters. Shank cutters have an integral arbor or shank and are mounted in the hole in the spindle nose or in an adapter or collet that fits the spindle nose. Face type cutters are fastened directly to the spindle nose by screw in the body of the cutter.

Milling cutters may have teeth on the periphery only, on the ends only or on the periphery and ends.

Peripheral teeth may be straight or helical.

Plain milling cutters are used for machining plane surfaces and are of cylindrical shape with teeth on the periphery only. Cutters under 3/4 in. in width are made with straight teeth; cutters with a wider face have spiral teeth.

Task I. Translate into Ukrainian. Pay attention to the constructions with Passive Infinitive.

I. a) the milling cutter to be used; b) the cutters to be mounted on the arbor; c) the shank cutter to be employed; d) the tool to be fastened; e) milling to be performed.

II. 1. The face cutters to be fastened directly to the spindle nose are fixed by a screw.

2. Shank cutters to be mounted in the hole of the spindle nose have an arbor or a shank.

3. Plain milling cutters to be used for machining plane surface are of cylindrical shape.

4. Helical mills to be applied for light cuts give а very smooth workpiece finish.

5. Side milling cutters to be need for straddle milling are similar to plain milling cutters.

6. Side milling cutters to be applied for side and face milling are similar to plain milling cutters.

Text II

Vocabulary Notes

  1. helical (plain) milling cutter (helical mill) – циліндрова фреза з гвинтовими зубами

helical milling cutter teeth

helical milling cutter removal

helical mill hardness

helical mill operation

  1. cut – різання

light cut – зняття легкої стружки

light cut rate

light cut quality

  1. deep – глибокий, depth – глибина

deep hole

hole depth

depth of cut

drilling depth

  1. smooth – гладкий, рівний, чистий

smooth face

smooth shank

smooth finish

  1. side milling cutter – трибічна фреза

side milling cutter treatment

side milling cutter design

side milling cutter depth of cut

  1. side milling, face milling – торцеве фрезерування

side milling operation

face milling rate

side milling quality

face milling depth of cut

  1. spiral end mill – спіральна пальцева фреза

spiral and mill application

spiral end mill depth of cut

spiral end mill size

  1. end face – торець, торцева поверхня

end face strength

end face shape

end face teeth

  1. cutting edge – ріжуча кромка, лезо

cutting edge shape

cutting edge treatment

teeth cutting edge

  1. body – корпус, тіло

face cutter body

end mill body

mill body size

Translate text II.

Milling Cutters

Helical milling cutters are plain mills with very few teeth. They are efficient on surfacing operations of considerable width and depth of cut. Helical mills are also used for light cuts where a very smooth finish is required and for light work.

Spiral end mills are similar to plain milling cutters but have teeth on the end face as well as on the periphery. End mills are used for a variety of surfacing operations.

Shell end mills are used with an arbor and are more economical than solid end mills of the same size.

Angular cutters differ from end and side milling cutters in that the straight cutting edges of the teeth are neither parallel nor perpendicular to the cutter axis.

Face type milling cutters are used for surfacing operations. The face cutter consists of a cylindrical body with inserted teeth with cutting edges on the periphery and on one face.

Task I. Translate into Ukrainian. Pay attention to “either … or”, “neither … nor” constructions.

  1. Peripheral teeth may be either straight or helical.

  2. Either drills or cutters may be used for treating these holes.

  3. Neither face nor radial cutters are used for this operation.

  4. The cutting teeth edges of angular cutters are neither parallel nor perpendicular to the cutter axis (axis - вісь)

  5. Shank cutters are mounted either in the spindle nose hole or in a collet.

Additional Reading

Task I. Translate the texts using the dictionary.

Text I

Milling Cutters

An end mill or a shell milling cutter has a chip-breaking thread in it. If the thread is run out to its full depth at the end of the cutter, the teeth at the end of the tool are either weakened unduly or are cut away. In either event the efficiency of the cutter is impaired. In a cutter the chip breaking groove is run right out at the end of the cutter but its depth is reduced towards the end face of the tool. All the cutting edges lie in the same cylindrical surface and the chip breaker grooves may have more than one start.

Text II

Rod and Bar Cutter

A new hydraulic cutter head cuts soft and medium hard rod and bar. A positioning cam holds the stock in correct position for cutting and shear type blades make square cut instead of conventional chisel type cut. Unit can be used with any hand or power operated hydraulic power supply.

Text III

Give the main idea of the text.

Milling cutters

The line of milling cutters includes 3 in. cutters with 0° and 15° lead angles using CNM-43 inserts, and with a 15° lead angle using SNM-43 inserts.

Also available are cutters in sizes from 4 in. dia. through 10 in. dia. that will accept the 5/8 in. SNM-54 and CNM-54 style inserts. Other additions are 8 in. and 10 in. dia. face mills. Cutters offer simplicity of design with generous chip clearance for good finishes.

What have texts IV and V in common?

Text IV

Indexable Blade End Mills

Prolite end mills are made in a wide range of sizes from 1/2 in. dia. to 1 1/2 in.dia. They are capable of machining most materials at high speeds and feeds. They incorporate inexpensive triangular tungsten carbide tips which can be easily locked into position and indexed three times before replacement. The cutter bodies are solid, heat treated steel castings, rigid and accurate. Prolite can be used for end milling, keyway machining, open end slotting, face milling and for tool and die making in addition to many other applications in general engineering.

Text V

Cuts Soft Materials Well

A line of high-speed steel end mill is designed for milling aluminum and other non-ferrous materials.

These straight-shank two-flute end mills have a 43° flute helix angle for producing fine finishes and long tool life.

Shanks are provided for tool holder screws. Rake angles and cutting-edge relief assure efficient milling in soft materials. Standard length is available in 13 diameters up to 2 in. Long and extra-long cutters are also available.

Text VI Translate into Ukrainian.

Chips Flow Freely

A line of carbide insert cutters is designed with large flutes to allow free chip flow. Simple construction is said to reduce spindle load and vibration and to permit rough cuts closer to finished size. Standard insert grades are 370 and 883. The cutters permit slot milling through solid material.

Text VII Translate into Ukrainian.

Insert Mills Cast Iron

A double-coated carbide insert has been developed for cast iron milling at moderate cutting speeds. Called GC 320, the insert is said to wear like a conventional, uncoated grade, but offers a sharp cutting edge with lower cutting forces. Cutting speed range is 230 to 430 fpm with feeds between .014 and .006 in.

Text VIII Translate the text using the dictionary.

Indexable Insert Cutters

A new milling cutter is intended for machining cast iron in quantity production applications especially in the car industry. Before now cutters with brazed blades have been dominant in this type of milling operation. The new cutter is now widely used to advantage in turning and milling.

The new milling cutter has indexable inserts. The location for each insert must be axially accurate. For milling tools the method of clamping the cutting edges is particularly important. When brazed blade cutters are employed, deformation of the cutter body is compensated for by grinding.

The inserts for the new cutter are triangular in shape. Each has six cutting edges. However, if inserts used in one cutter were transferred to another of the opposite hand, further six edges could be used. Thus twelve cutting edges would be available from an insert used first in a left- then in a right-hand cutter.

These inserts are positioned in the cutter body at an angle of 43 degrees to the work surface. The clamping device is designed not to distort the cutter body.

Text IX Read the text.

Inserts of superior grade cemented carbide are recommended for milling. The new cutter with indexable inserts was installed on the transfer line and is used to machine the 45 deg cylinder blocks for camshaft engines installed on cars. Rough milling of the end faces of the block is performed. A life of 750 blocks per regrind was obtained with brazed cutters; with the indexable insert cutters the life was found to be 1250 blocks per cutting edge. With 44 teeth the 12 diameter insert cutter was used with a speed of 90 rev/min and feed of 0.562 in/rev. The depth of cut was from 1/8 to 3/16 in. The new cutter can stand up to machining cast iron at high metal removal rates; the tool costs for the milling operations might be halved by the use of indexable tips.

For finish milling operations engineers have designed another milling cutter which is equipped with square inserts.

Text X Translate into Ukrainian.

Metal cutting tools are designed for producing various components. While cutting the tool, tips are continuously cutting into the workpiece removing the material in the form of chips.

There are various cutting tools in practice.

Turning tools are the most versatile of all cutting tools. Bull-nose (turning) tools - roughing and finishing - are widely used in shop practice because of their rigidity and versatility. Bull-nose tools provide better surface finish. Turning (bull-nose) tools are applied for turning external cylindrical and taper surfaces.

According to the direction of longitudinal feed the lathe tools may be right-cut when the feed is performed from right to left (e.g. right-cut bull-nose roughing tools) and left-cut when the feed is performed from left to right (e.g. left-cut bull-nose roughing tools).

According to their shape the lathe tools may be straight (straight left- and straight right-cut tools) and bent (bent left-cut and bent right-cut roughing and cutting-off tools).

Tapering is made by using a wide turning tool for turning outside and inside surfaces of small length.

Drilling, counterboring, countersinking and reaming are performed by drills, counterbores, countersinks and reamers.

Boring of pre-drilled holes is performed by boring tools.

Milling cutters are used for milling. There are many types and shapes of cutters such as face cutters, side cutters, radial cutters, end cutters, form cutters etc.

Threading belongs to the most accurate types of work performed on screw-cutting lathes.

Thread on small workpieces is cut by taps (internal threads) and threading dies (external threads). The taps and threading dies are clamped in the drill chuck.

Carbide and ceramic cutting tools have their bits brazed, cemented or welded on to the shank.

Cutting tool developments are providing hew potential for making metalcutting operations more productive and cost-efficient.