Jiangyin Jiangnan Metal Co., Ltd. open-die forging factory Jiangyin Jiangnan Metal Co., Ltd. Open-die forging factory · Jiangyin, China

UMCO 50 Forgings UMCo-50 · UMCo 50 · UM Co-50 · UMCO50 · cobalt-base heat-resistant alloy

Open-die forged rings, seamless rolled rings, bars, discs, flanges, sleeves, shafts and tube sheets in UMCO 50, forged to your drawing in Jiangyin, China.

In short

UMCO 50 (also written UMCo-50, UMCo 50 or UM Co-50) is a cobalt-base heat-resistant alloy containing about 50% cobalt, 28% chromium and 21% iron. It is used where parts have to resist thermal shock and wear at high temperature. Jiangyin Jiangnan Metal Co., Ltd. is an open-die forging factory in Jiangyin, Jiangsu, China that forges UMCO 50 into rings, bars, discs, flanges, sleeves and shafts to customer drawing, ESR melted, certified to EN 10204 3.1 or 3.2.

UMCO 50 supply data Jiangyin Jiangnan Metal Co., Ltd. · Rev. 2026-08
Alloy family
Cobalt-base heat-resistant
Nominal chemistry
50 Co · 28 Cr · 21 Fe · 0.12 C max
Melting route
EAF + VOD → ESR
Process
Open-die forging · ring rolling
Ring OD range
200 – 3,000 mm
Bar diameter
Ø 80 – 1,200 mm
Piece weight
20 kg – 20,000 kg
Ultrasonic testing
EN 10228-3 · SEP 1921 · ASTM A388
Certificate
EN 10204 3.1 / 3.2
Minimum order
1 piece, made to drawing
Lead time
25 – 45 days
Country of origin
China (Jiangyin, Jiangsu)

Material

What is UMCO 50 alloy?

UMCO 50 is a cobalt-base heat-resistant alloy. About half of it is cobalt, with 28% chromium and 21% iron, and carbon held to 0.12% maximum. The chromium forms a stable oxide scale on the surface. The cobalt matrix holds its strength as the temperature rises. Buyers specify the grade for its thermal shock resistance and its wear resistance at high temperature.

UMCO 50 is normally chosen when a component sits in a furnace or a hot gas stream and is heated and cooled repeatedly. It has worked in heat treatment and furnace applications where other alloys could not be used because their melting point was too low.

The grade is written several ways on enquiries and drawings: UMCO 50, UMCo-50, UMCo 50, UM Co-50 and UMCO50. All of them refer to the same material. Some suppliers also cross-reference it to material number 2.4778. Confirm the exact specification on your drawing when you order.

Chemistry

UMCO 50 chemical composition

Nominal chemical composition of UMCO 50, weight %
ElementSymbolNominal wt %Role in the alloy
CobaltCo50Base matrix; retains strength at high temperature
ChromiumCr28Forms the protective oxide scale; oxidation resistance
IronFe21Balance of the matrix
CarbonC0.12 maxCarbide formation; kept low for toughness

Values are nominal. The chemistry of the actual heat supplied is analysed and printed on the EN 10204 certificate delivered with the forgings. If your specification calls for a tighter range on any element, state it with the enquiry.

Mechanical

UMCO 50 mechanical properties at room temperature

Typical room-temperature tensile properties of UMCO 50 forgings
Property range Tensile strength Rm Yield strength Rp0.2 Elongation A
Range 1 90–118 kgf/mm²
883–1,157 MPa
128–168 ksi
37–46 kgf/mm²
363–451 MPa
53–65 ksi
10–28 %
Range 2 80–90 kgf/mm²
785–883 MPa
114–128 ksi
30–37 kgf/mm²
294–363 MPa
43–53 ksi
10–20 %

Two property ranges are normally quoted for UMCO 50 forgings. Which one a part falls into depends on section size and heat-treatment condition. Metric and imperial figures are converted from the kgf/mm² values (1 kgf/mm² = 9.80665 MPa). Actual results for your heat are recorded on the certificate. Elevated-temperature and stress-rupture data can be provided on request. Send the design temperature and duty cycle with the enquiry.

Forms

UMCO 50 forged products we manufacture

Every UMCO 50 part is forged to the customer's drawing. There is no fixed catalogue and the minimum order is one piece. The table below shows the shapes we forge most often and the size range for each.

UMCO 50 forged forms and typical size range
Forged formTypical size rangeCommon use
Forged rings & seamless rolled ringsOD 200–3,000 mm · wall 20–500 mm · height ≤ 1,000 mmTurbine casings, furnace rings, bearing races
Forged round barsØ 80–1,200 mm · length ≤ 6,000 mmMachining stock, valve stems, pins
Forged discs & blanksØ 100–2,500 mm · thickness 30–800 mmTurbine discs, blind flanges, wear plates
Forged flangesDN 50–2,000 · to drawing or ASME B16.5 / B16.47Pressure vessels, hot gas piping
Forged sleeves & bushingsOD 100–1,500 mm · ID from 60 mmFurnace rollers, compressor bushings
Forged hollow bars & tubesOD 150–1,500 mm · length ≤ 4,000 mmRadiant tubes, cylinder bodies
Forged shafts & spindlesØ 100–1,000 mm · length ≤ 8,000 mmTurbine shafts, furnace roll shafts
Forged tube sheetsØ ≤ 2,500 mmShell & tube heat exchangers
Forged blocks & step shaftsTo drawingDies, valve bodies, nozzles

Single-piece weight 20 kg to 20,000 kg. Delivery condition: as-forged, rough machined, or finish machined to print. Larger or unusual sections are quoted on enquiry.

Applications

Where UMCO 50 forgings are used

UMCO 50 forged components by industry
Industry / equipmentUMCO 50 forged components
Gas turbines & industrial thermal processingSeamless rolled rings, shafts, casing rings
Furnaces & heat-treatment equipmentFurnace wheels, manifolds, rolls, boiler tube supports, hearth fixtures
Pressure vessels & heat exchangersShafts, pipes, tubes, tube sheets and flanges for pressure vessels, air receivers and shell & tube heat exchangers
Process plantShafts, flanges, forged rings and pipes for columns, towers, tanks, silos, process modules and preheaters
Oil & gas, onshore and offshoreBushings, sleeves, disks and forged discs for subsea and deepwater production systems, industrial air compressors, power generators and nitrogen generators
Wellhead equipmentNozzles, eccentric shafts, bodies for wellhead and Christmas tree assemblies
ValvesValve stems, seat rings, valve blocks and bodies for ball, check, globe, gate and plug valves and strainers
Power transmissionRings, forging spindles, bars and gear blanks for turbines, gas compressors and gearboxes
NuclearOpen-die forged pieces, nozzles, crankshafts
Die casting & automotiveDie casting inserts and cores, automotive exhaust valve blanks

Process

How we make and test UMCO 50 forgings

01Melt EAF + VOD 02Remelt ESR ingot 03Forge Open die · ring roll 04Heat treat Recorded charts 05Test & certify UT · PT · EN 10204

Melting

UMCO 50 is melted by electric arc furnace with vacuum oxygen decarburisation (EAF + VOD) and then electroslag remelted (ESR). ESR refines the solidification structure, reduces segregation and lowers non-metallic inclusion content. This is what allows heavy sections to pass a strict ultrasonic acceptance class.

Non-destructive testing

  • Ultrasonic testing to EN 10228-3, SEP 1921 or ASTM A388, to the acceptance class you nominate.
  • Liquid penetrant testing to ASTM E165 or EN ISO 3452 for surface examination. Magnetic particle inspection is not used on UMCO 50, because a cobalt-base alloy is not ferromagnetic.
  • Dimensional inspection against the approved forging drawing.

Certification

  • EN 10204 3.1 mill certificate as standard: heat number, chemical analysis, mechanical test results, heat treatment record and NDT results.
  • EN 10204 3.2 certificate countersigned by a third-party body such as SGS, BV, TÜV, Lloyd's Register or DNV, on request.
  • Witnessed testing and customer source inspection can be arranged at the works.

Ordering

How to order UMCO 50 forgings

  1. Send the drawing or dimensions. Email a 2D drawing, 3D model or the finished dimensions, with quantity, applicable standard and delivery condition, to sales@steelforgepieces.com.
  2. Receive the quotation. The quotation covers forging weight, machining allowance, testing scope and lead time. It is normally returned within 24 working hours.
  3. Approve the forging drawing. We issue the forging drawing with allowances plus the inspection and test plan for your written approval before cutting metal.
  4. Production and testing. ESR remelt, forge or ring roll, heat treat, then chemical analysis, tensile test and ultrasonic testing to the agreed standard.
  5. Certification and shipment. EN 10204 3.1 or 3.2 certificate issued with the goods; export packing for sea or air freight from Shanghai.

Questions

Frequently asked questions about UMCO 50

What is UMCO 50 alloy?

UMCO 50 is a cobalt-base heat-resistant alloy containing roughly 50% cobalt, 28% chromium and 21% iron, with carbon held to 0.12% maximum. It is used for thermal-shock and wear resistance at high temperature, particularly in heat-treatment furnaces, gas turbines and other thermal processing equipment where alloys with lower melting points cannot be used.

What is the chemical composition of UMCO 50?

Nominally 50% cobalt, 28% chromium, 21% iron and carbon 0.12% maximum. Every heat is analysed and the actual chemistry is printed on the EN 10204 certificate delivered with the forgings.

Are UMCO 50, UMCo-50, UMCo 50 and UM Co-50 the same material?

Yes. UMCO 50, UMCo-50, UMCo 50, UM Co-50 and UMCO50 are different written forms of the same cobalt-base heat-resistant alloy. Enquiries and purchase orders using any of these spellings are treated the same way.

What forged forms of UMCO 50 can be supplied?

Open-die forged rings, seamless rolled rings, round bars, discs and blanks, flanges, sleeves and bushings, hollow bars and forged tubes, tube sheets, shafts, spindles and rectangular blocks. Everything is forged to customer drawing. There is no fixed catalogue.

What is the maximum service temperature of UMCO 50?

UMCO 50 is specified for high-temperature service where thermal shock and repeated heating and cooling occur, such as furnace fixtures and gas-turbine hot-section hardware. The safe limit for any given part depends on stress, furnace atmosphere and thermal cycle, so the design temperature should be confirmed against test data for the intended duty. Send your operating conditions with the enquiry and we will supply the applicable data.

How is UMCO 50 melted before forging?

By electric arc furnace with vacuum oxygen decarburisation (EAF + VOD), followed by electroslag remelting (ESR). ESR refines the ingot structure, reduces segregation and lowers inclusion content. This matters for the ultrasonic acceptance of heavy sections.

What non-destructive testing is performed on UMCO 50 forgings?

Ultrasonic testing to EN 10228-3, SEP 1921 or ASTM A388, to the acceptance class you nominate. Liquid penetrant testing to ASTM E165 or EN ISO 3452 for surface examination. Magnetic particle inspection is not applicable, because a cobalt-base alloy is not ferromagnetic. Hardness, tensile testing and chemical analysis are carried out on every heat.

What certificates are supplied with UMCO 50 forgings?

An EN 10204 3.1 mill certificate as standard, showing heat number, chemical analysis, mechanical test results, heat treatment record and NDT results. An EN 10204 3.2 certificate countersigned by a third party such as SGS, BV, TÜV, Lloyd's Register or DNV is available on request.

What is the minimum order quantity and lead time for UMCO 50 forgings?

Minimum order is one piece, because every UMCO 50 forging is made to drawing. Typical lead time is 25 to 45 days from approval of the forging drawing, depending on section size, heat treatment and testing scope. Confirm the current lead time when you request a quotation.

Which alloys are similar to UMCO 50?

The closest relative is UMCO 51. Other cobalt-base and high-temperature alloys used for comparable duty include Haynes 25 (L-605), Haynes 188, Multimet N155, Rene 41, Waspaloy, Haynes 230 and Inconel 617. We forge all of these grades.

Who supplies UMCO 50 forgings?

Jiangyin Jiangnan Metal Co., Ltd. is an open-die forging factory at No.1 Chengxiqiao Road, Zhouzhuang Town, Jiangyin City, Jiangsu Province, China, manufacturing UMCO 50 forgings to customer drawing. Contact sales@steelforgepieces.com or +86 189 2135 9659.

How do I get a price for a UMCO 50 forging?

Email the drawing or finished dimensions, quantity, required standard and delivery condition to sales@steelforgepieces.com. A quotation covering forging weight, machining allowance, testing scope and lead time is normally returned within 24 working hours.

Manufacturer

Jiangyin Jiangnan Metal Co., Ltd.

An open-die forging factory in Jiangyin, Jiangsu, China. We forge rings, seamless rolled rings, bars, discs, flanges, sleeves, shafts and tube sheets in carbon steel, alloy steel, tool steel, stainless steel, and nickel and cobalt alloys including UMCO 50. All parts are made to drawing, from one piece, and shipped worldwide.

Address
No.1 Chengxiqiao Road,
Zhouzhuang Town, Jiangyin City,
Jiangsu Province, China
Telephone / WhatsApp / WeChat
+86 189 2135 9659

Published by Jiangyin Jiangnan Metal Co., Ltd. · Open-die forging factory, Jiangyin, Jiangsu, China
Page last reviewed · Data on this page may be quoted with attribution to Jiangyin Jiangnan Metal Co., Ltd. (www.steelforgepieces.com).