Can you supply a girth gear without the original drawing?

Yes. Send the worn gear or its mating pinion and we measure the unworn references, reconstruct the module and tooth count, and send the drawing back for approval before machining.

Do you machine the pinion together with the gear?

Where both parts come to us, yes. Cutting and checking them as a set is the reliable way to keep the contact pattern right, especially when the old pinion is also worn.

What is the largest cement mill gear you can cut?

Up to 8 m outside diameter on the gear-cutting machines, with turning capacity of 8 m and shafts up to 12 m. Send the size and we will confirm the set-up before quoting.

Which material and hardness do you use?

The grade and hardness on your drawing come first. We verify the blank against its mill certificate, record hardness after heat treatment, and agree any substitute with you before cutting.

How long does a replacement girth gear take?

Usually four to eight weeks from the approved drawing, depending on size, module and heat treatment. The date is confirmed with the quotation.

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Girth gears and mill parts
for cement plants.

A cement line stops when one drive part fails. We machine the girth gears, pinions, shafts, shells and housings that keep kilns and mills turning — to your drawing, or measured from the part that came out.

Parts we machine for cement plants

Kiln duty and mill duty are not the same

A kiln turns slowly under high torque and carries its own heat; a mill runs continuously and is hammered by the charge. The two wear a girth gear differently. Kiln teeth tend to wear on one flank while the gear fights axial movement; mill teeth see impact and abrasive dust. The replacement has to be machined for the duty, not only for the diameter.

Split gears are machined as a pair

Cement girth gears are usually split so they can be changed without removing the shell. Both halves are roughed, stress-relieved and finish-cut in the same set-up, with the joint faces bolted together. They are pre-assembled and match-marked before dispatch, so the tooth pitch and the joint line agree when the halves are bolted on site.

The gear is only part of the drive

A worn gear usually arrives with a worn pinion, a scored shaft or a housing with a loose fit. We read the whole drive: pinion and gear as a set, shaft journals against the bearing bore, housing faces against the datum the drive is aligned from. Machining the mating parts together keeps a new gear off an old, mismatched pinion.

Material and heat treatment follow the drawing

Blanks are cast, forged or rolled with a mill certificate, and the grade is verified on receipt. Quenching and tempering precede tooth cutting; induction hardening follows it where the drawing calls for a hard tooth surface. Hardness and case depth are recorded, and any substitute grade is agreed with you before machining.

What the shop can hold

Gears up to 8 m outside diameter, work up to 8 m in turning diameter, shafts up to 12 m between centres, and single castings or forgings up to 35 t. Hobbing, shaping, induction hardening and inspection happen in the same workshop, so a large gear does not travel between suppliers.

Inspection before the crate

Ultrasonic testing on the blank where specified, hardness after heat treatment, and a dimensional record covering bore, face runout, pitch and tooth thickness. Reports travel with the part and can be issued in English for export. If your maintenance team works to a report template, send it with the enquiry.

When there is no drawing

Older kilns and mills often outlive their paperwork. Send the worn part or the mating pinion; we measure the references that did not run, reconstruct the tooth data and issue a drawing for your approval before cutting. One piece is enough — there is no pattern charge and no minimum order.

Packing for a plant site

Split gears are braced and match-marked; shafts are protected at the journals and lifted from marked points. Crates are packed for sea freight with rust protection, and the packing list names every piece so the site can check the delivery against the drawing set.

Cement plant drive questions

Can you supply a girth gear without the original drawing?: Yes. Send the worn gear or its mating pinion and we measure the unworn references, reconstruct the module and tooth count, and send the drawing back for approval before machining.
Do you machine the pinion together with the gear?: Where both parts come to us, yes. Cutting and checking them as a set is the reliable way to keep the contact pattern right, especially when the old pinion is also worn.
What is the largest cement mill gear you can cut?: Up to 8 m outside diameter on the gear-cutting machines, with turning capacity of 8 m and shafts up to 12 m. Send the size and we will confirm the set-up before quoting.
Which material and hardness do you use?: The grade and hardness on your drawing come first. We verify the blank against its mill certificate, record hardness after heat treatment, and agree any substitute with you before cutting.
How long does a replacement girth gear take?: Usually four to eight weeks from the approved drawing, depending on size, module and heat treatment. The date is confirmed with the quotation.

Send the drawing, or the part that failed.

Tell us the kiln or mill, the part and what it is doing. We reply with what we can measure, the material questions we still need answered, and a date.

Send a drawing or a photo

Girth gears and mill partsfor cement plants.