Transmission and Powertrain Castings
Made in Coimbatore

Technocast Foundry casts gearbox and transfer cases, differential housings, flywheel hubs, pulleys and gear blanks in ductile (SG) iron, grey iron and steel, from 1 kg to 1,500 kg. The foundry, CNC machine shop, gear shaper and balancing machines are all on one site at Arasur, on the eastern side of Coimbatore, Tamil Nadu, India.

Transmission and Powertrain

Which Transmission Parts
Do We Cast?

Cored, cased iron and steel parts that have to stay tight and true after machining.

Transmission and powertrain work is about 15 per cent of everything we pour, and it is some of the most demanding. Gearbox and transfer cases, differential housings, flywheel and damper hubs, pulleys, ring gear blanks, bearing covers and end plates - parts that have to be pressure tight, dimensionally stable and concentric once they are machined.

Most of these are cored and cased parts, so they need reliable cores and a mould that will not move. Cold box cores make up 70 per cent of our core output, with shell and CO2 covering the rest. Weight runs from small covers up to housings of 1,100 kg, so the moulding route is chosen part by part across the DISA, ARPA and No Bake lines.

What separates transmission work is what happens after casting. A Fellows gear shaper cuts to 500 mm diameter, dynamic balancing is accurate to 1 gram, and the larger Brown and Sharpe coordinate measuring machine does gear profile testing. All of it on one site at Arasur, Coimbatore, so a housing is not shipped between three vendors to be finished.

Why This Work Runs Here

What Does Transmission
Work Actually Need?

Good cores, a settled casting, few machining setups and real gear capability. Missing any one of them and the housing goes out to a third party halfway through.

Complex Cores, Repeatably

Cased parts live or die on cores. Five cold box shooters from 5 kg to 30 kg, a 5 kg shell core shooter and a four-table CO2 facility. Cold box covers 70 per cent of core output, shell 20 and CO2 10.

5 cold box shooters Shell CO2 5-30 kg

Stress Relieved Before Machining

A housing moves after it is cut if the casting has not settled first. Stress relieving, normalising, annealing, hardening and tempering, and induction hardening are all done at Arasur, not sent out and back.

Stress relieving Normalising Annealing

Single-Setting Machining

Four horizontal machining centres, including a MAG Specht 500X five-axis and a Starrag IWK 5000, so a housing is bored and faced in fewer settings. Twenty vertical centres, all with a 4th axis and through-coolant spindle.

DHM 800 Starrag IWK 5000 MAG Specht 500X VTM

Gear Work and Balancing

A Fellows gear shaper from Vermont, USA, cuts to 500 mm diameter and 90 mm height. Horizontal and vertical dynamic balancing covers 500 mm diameter and 300 mm length, accurate to 1 gram.

Gear shaping to 500 mm Dynamic balancing 1 gram accuracy

Specifications

What Are the Specs for
Transmission Castings?

Send a drawing and we will confirm against your part. The figures below are the working envelope at Arasur, Coimbatore.

Item What We Offer
MaterialsDuctile (SG) iron EN-GJS-400-18 to EN-GJS-900-2, grey iron EN-GJL-250 to EN-GJL-300, cast steel to IS 1030 and ASTM A27 / A148 / A216, alloy steel to IS 7598 and ISO 683-7
Typical part weight1 kg to 1,500 kg in a single piece. Transmission housings commonly run 70 kg to 1,100 kg
Moulding routesDISA MATCH 130 high pressure for volume, ARPA 450 and ARPA 1300 for mid weights, Alpha-set No Bake for the heaviest housings
Core makingFive cold box shooters from 5 kg to 30 kg, a 5 kg shell core shooter, and a four-table CO2 facility
Heat treatmentStress relieving, normalising, annealing, hardening and tempering, and induction hardening
Machining20 VMC with 4th axis and through-coolant, 4 HMC including a five-axis, 5 VTL, 13 turning centres, and vertical turn mill to 1,750 mm diameter
Gear and balancingFellows gear shaper to 500 mm diameter and 90 mm height. Dynamic balancing to 500 mm diameter and 300 mm length, accurate to 1 gram
MeasurementTwo Brown and Sharpe CMMs: 700 x 1,000 x 700 mm with touch probe, and 1,500 x 1,200 x 1,000 mm with scanning probe and gear profile testing
TestingUltrasonic and magnetic particle inspection, pressure testing on housings, contour testing and ring gauge masters
Supply conditionRaw casting, machined, painted, or fully assembled and tested

Applications

Which Driveline Parts
Do These Castings Become?

Six part families we run regularly for transmission and powertrain builders.

Gearbox and Transfer Cases

Cored, cased ductile iron parts that must stay pressure tight after machining. Bored on the horizontal centres and pressure tested where the drawing calls for it.

Differential Housings

Heavier cased parts, commonly 70 kg to 1,100 kg, moulded on ARPA or the No Bake line and machined on the vertical turret lathes.

Flywheel and Damper Hubs

Rotating parts where imbalance becomes vibration. Dynamically balanced to 1 gram before they leave the shop.

Pulleys and Belt Drives

Grey iron pulleys and drive wheels, where damping and clean machining matter more than tensile strength.

Ring Gears and Gear Blanks

Blanks turned and gear cut on the Fellows shaper to 500 mm diameter, then checked for gear profile on the scanning-probe CMM.

Bearing Covers and End Plates

Higher-volume flat parts on the DISA high pressure line, machined in batches so the bolt pattern repeats part to part.

Quality Gates

How Are Transmission
Castings Checked?

Six checks between the furnace and the packing bay. A part that fails one does not move to the next.

Melt Chemistry

Every heat is read on an ARL spectrometer before pouring, and the result is recorded against the batch.

Nodularity Check

Ductile iron is checked by ultrasonic velocity, then confirmed under a microscope with image analyser for graphite shape and count.

Mechanical Testing

Tensile strength, elongation and hardness are tested on samples poured from the same heat as your housings.

Dimensional Proving

Bores, faces and gear profiles are proven on the 1,500 x 1,200 x 1,000 mm Brown and Sharpe CMM with a scanning probe.

Soundness

Ultrasonic and magnetic particle inspection in house, plus pressure testing on cased parts. Radiographic inspection through an accredited partner when specified.

Final Inspection and Packing

Balancing where required, then paint, packing and the documentation pack for your incoming inspection.

Common Questions

Transmission Casting
Questions, Answered

Where is your transmission casting foundry located?

At 127/3B, Sangothipalayam Road, Arasur, Coimbatore, Tamil Nadu 641407, India. The foundry, CNC machine shop, gear shaper and balancing machines are all on the same site.

What transmission and powertrain castings do you make?

Gearbox and transfer cases, differential housings, flywheel and damper hubs, pulleys and belt drives, ring gears and gear blanks, and bearing covers and end plates.

What weight range do transmission housings run to?

1 kg to 1,500 kg in a single piece. Transmission housings commonly sit between 70 kg and 1,100 kg, moulded on the ARPA or No Bake lines.

Do you cut gears in house?

Yes. A Fellows gear shaper from Vermont, USA, cuts to 500 mm diameter and 90 mm height, and gear profile is checked on the Brown and Sharpe scanning-probe coordinate measuring machine.

Can you dynamically balance castings?

Yes. Horizontal and vertical balancing machines cover parts to 500 mm diameter and 300 mm length, accurate to 1 gram.

Are transmission housings pressure tested?

Yes, where the drawing calls for it. Pressure testing is done in house after machining, alongside ultrasonic and magnetic particle inspection.

Which materials do you use for transmission castings?

Ductile (SG) iron in EN-GJS-400-18 to EN-GJS-900-2, grey iron in EN-GJL-250 to EN-GJL-300, cast steel to IS 1030 and ASTM A27, A148 and A216, and alloy steel to IS 7598 and ISO 683-7.

Do you supply customers in Tamil Nadu as well as export?

Yes. Around 25 per cent of output stays in India, and the rest is exported, mainly to the United States, Europe and the rest of Asia. Customers in Coimbatore and across Tamil Nadu are welcome to visit the plant at Arasur.

Certifications

ISO 9001:2015
ISO 14001:2015
ISO 45001:2018
IATF 16949:2016
PED Certified

Send a Drawing

Looking for a Transmission
Casting Supplier in Coimbatore?

Send the drawing with the material grade, the single-piece weight, the annual volume and any gear or balancing requirement. You get back the moulding route, a lead time and a price.