KOREA TUNGSTEN CO.,LTD

Screws · Nuts · Rivets

Tungsten and molybdenum boats and crucibles for vacuum deposition and high-temperature melting. They are used where the vessel must not react with molten metal, and are built to your required shape and capacity.

2,623 °CMelting point of molybdenumFar higher than a steel bolt

99.95 % +Material purityLow outgassing in high vacuum

To drawingThread specificationPitch and grade specified

Hex · countersunkHead formSelected by application

2,623 °CMelting point of molybdenumFar higher than a steel bolt

99.95 % +Material purityLow outgassing in high vacuum

To drawingThread specificationPitch and grade specified

Hex · countersunkHead formSelected by application

Applied parts

Used as the evaporation source in vacuum coaters, the melting crucible in high-temperature furnaces and the vessel in crystal growth equipment. Material and shape are designed around what it will hold and at what temperature.

No photos registered100 %Scroll to zoom · drag to pan

MaterialTungsten (W) · Molybdenum (Mo)

Purity99.95 % and above

ProductionMachined and thread rolled

SizeBolts to drawing

Head formHex · countersunk · round

Service environmentHigh temperature · high vacuum

Size, form and grade are set by the fastening conditions. Tell us the drawing or the existing part and we will confirm and reply.

No products added

No photos registered100 %Scroll to zoom · drag to pan

MaterialTungsten (W) · Molybdenum (Mo)

Purity99.95 % and above

ProductionMachined and thread rolled

SizeBolts to drawing

Head formHex · countersunk · round

Service environmentHigh temperature · high vacuum

Size, form and grade are set by the fastening conditions. Tell us the drawing or the existing part and we will confirm and reply.

No products added

KEY FEATURES

It must not loosen at high temperature

Steel bolts stretch and seize at high temperature.

Low thermal expansion and high strength at temperature keep the clamping force through repeated heating.

High-temperature strength

High Temperature Strength

Molybdenum 2,623 °C. It holds its clamping force at temperatures where steel softens.

Low thermal expansion

Low Expansion

Through repeated heating and cooling, it loosens or binds far less.

Low outgassing

Low Outgassing

Outgassing in high vacuum is low, so it does not unsettle the chamber pressure.

Melting points by material

Tungsten (W)3422

Molybdenum (Mo)2623

Stainless steel bolt1450

Melting point °C. The higher the figure, the longer the clamping force holds at high temperature.

Why it seizes

At high temperature, identical materials in contact weld together. Material pairing and surface are set together.

Reuse

It is a consumable, but reuse is possible depending on conditions. The grade is set in light of the replacement interval.

KEY FEATURES

It must not loosen at high temperature

Steel bolts stretch and seize at high temperature.

Low thermal expansion and high strength at temperature keep the clamping force through repeated heating.

High-temperature strength

High Temperature Strength

Molybdenum 2,623 °C. It holds its clamping force at temperatures where steel softens.

Low thermal expansion

Low Expansion

Through repeated heating and cooling, it loosens or binds far less.

Low outgassing

Low Outgassing

Outgassing in high vacuum is low, so it does not unsettle the chamber pressure.

Melting points by material

Tungsten (W)3422

Molybdenum (Mo)2623

Stainless steel bolt1450

Melting point °C. The higher the figure, the longer the clamping force holds at high temperature.

Why it seizes

At high temperature, identical materials in contact weld together. Material pairing and surface are set together.

Reuse

It is a consumable, but reuse is possible depending on conditions. The grade is set in light of the replacement interval.

2,623°CMelting point of molybdenum

99.95% +Material purity

DrawingbasisThread specification

2,623°CMelting point of molybdenum

99.95% +Material purity

DrawingbasisThread specification

DESIGN PRECISION

The specification is set to the fastening conditions

In a fastener, specification and material pairing are what distinguish the product.

In the same bolt, changing the material pairing and the surface changes how it welds and loosens.

Drawingbasis

Thread specification

Diameter, pitch, length and grade are machined as drawn.

Hexor countersunk

Head form

Chosen to the tooling and the seating face conditions.

W · Mochoice

Material selection

Tungsten where the highest temperature is needed, molybdenum where machinability is.

We do not pick a specification, we develop it with you. (Give us the service temperature and the fastening conditions, and we will work out the specification with you.)

DESIGN PRECISION

The specification is set to the fastening conditions

In a fastener, specification and material pairing are what distinguish the product.

In the same bolt, changing the material pairing and the surface changes how it welds and loosens.

Drawingbasis

Thread specification

Diameter, pitch, length and grade are machined as drawn.

Hexor countersunk

Head form

Chosen to the tooling and the seating face conditions.

W · Mochoice

Material selection

Tungsten where the highest temperature is needed, molybdenum where machinability is.

We do not pick a specification, we develop it with you. (Give us the service temperature and the fastening conditions, and we will work out the specification with you.)

APPLICATIONS

Applications

The fields where fasteners are used. Specification and form differ by position.

Inside heat treatment furnacesThey fix jigs and structures inside high-temperature furnaces.

Vacuum equipmentUsed to fasten parts inside chambers.

Heating element mountingUsed as the fastening that holds heaters and electrodes.

Shielding structuresUsed to assemble shielding plates and reflectors.

High-temperature jigsUsed as assembly parts in jigs that are heated repeatedly.

Replacement partsWe reproduce the fasteners of existing plant to drawing.

Heat treatment furnacesvacuum equipmentheating element mountingshielding structures

APPLICATIONS

Applications

The fields where fasteners are used. Specification and form differ by position.

Inside heat treatment furnacesThey fix jigs and structures inside high-temperature furnaces.

Vacuum equipmentUsed to fasten parts inside chambers.

Heating element mountingUsed as the fastening that holds heaters and electrodes.

Shielding structuresUsed to assemble shielding plates and reflectors.

High-temperature jigsUsed as assembly parts in jigs that are heated repeatedly.

Replacement partsWe reproduce the fasteners of existing plant to drawing.

Heat treatment furnacesvacuum equipmentheating element mountingshielding structures

LEAD TIME

Fabrication and Lead Time

This product is made to your drawing. Here is the process, step by step.

STEP 01

Drawing received

Send us the thread specification, head form, length and service temperature.

Reply within 1 day

STEP 02

Specification review

We review the material and the thread production method and advise on whether to coat.

2 – 4 days

STEP 03

Thread production

Threads are rolled or machined and the head form produced.

By agreement, depending on the production schedule

STEP 04

Inspection · delivery

Thread dimensions and tightening torque are verified, and the part ships with a test report. Repeat orders to the same drawing skip the review stage.

By agreement, depending on the production schedule

Minimum quantity

From small quantities

Varies with specification and quantity.

Standard lead time

About 2 – 3 weeks

From drawing approval. Special sizes add tooling preparation time.

Supplied with it

Test report

Thread dimensional measurements are sent with the delivery.

LEAD TIME

Fabrication and Lead Time

This product is made to your drawing. Here is the process, step by step.

STEP 01

Drawing received

Send us the thread specification, head form, length and service temperature.

Reply within 1 day

STEP 02

Specification review

We review the material and the thread production method and advise on whether to coat.

2 – 4 days

STEP 03

Thread production

Threads are rolled or machined and the head form produced.

By agreement, depending on the production schedule

STEP 04

Inspection · delivery

Thread dimensions and tightening torque are verified, and the part ships with a test report. Repeat orders to the same drawing skip the review stage.

By agreement, depending on the production schedule

Minimum quantity

From small quantities

Varies with specification and quantity.

Standard lead time

About 2 – 3 weeks

From drawing approval. Special sizes add tooling preparation time.

Supplied with it

Test report

Thread dimensional measurements are sent with the delivery.

HANDLING

Handling precautions

These apply to refractory metals in general. Service life depends heavily on how the parts are handled.

Do not touch the parts with bare hands after unpacking. Oil from fingerprints carbonizes at high temperature and becomes a contaminant.

The material is weak against impact and bending. Tungsten is brittle at room temperature and can crack if dropped.

Do not heat above 500°C in air; oxidation accelerates sharply. Always use the parts in a vacuum or an inert atmosphere.

Avoid rapid heating and cooling. On first use, we recommend pre-heating (aging) at low current.

Store indoors in a dry place and keep the moisture-barrier packaging intact.

If your installation or operating conditions are unusual, our engineers will review them in advance. Send a drawing or your process conditions and we will start by selecting the right material with you.