Zambello gearbox repair — USA

Zambello Gearbox Repair and Replacement

Factory trained by Zambello in ItalyTwin-screw repairRepair, or a new Zambello fitted to your lineHousing line boring in house6–10 week rebuild10-ton lift
01. Zambello gearboxes

Zambello gearbox repair by a factory-trained shop

Zala Machine Co. repairs, rebuilds and replaces Zambello extruder gearboxes for plants across the United States. The work is done in our own shop in Hillsborough, New Jersey, on single-screw and twin-screw boxes from lab-scale units to heavy-duty production gearboxes.

Trained by Zambello in Italy

Martin Zala, who runs the shop, trained with Zambello at two of their locations in Italy. The training focused on twin-screw gearbox repair: how the boxes are built, how the gear trains are timed, and where they wear and fail. That knowledge comes back to our bench on every Zambello gearbox we open.

Zambello repair and replacement from one shop

Plants come to us directly to repair, rebuild or replace Zambello gearboxes. Most of the Zambello gearboxes repaired in this country come across our bench. We evaluate the box, tell you whether repair or replacement is the better answer, and carry out either one.

Repair, or a new Zambello fitted to your line

Not every gearbox is worth rebuilding. When a repair makes sense, we repair it. When it does not, we supply a new Zambello gearbox and make it fit the line you already have. A new box rarely drops straight into an old footprint, so we machine the gearbox-to-extruder adapter, build floor risers that bolt to the existing floor mounts, and make any other modifications needed to bring the new gearbox to the right height, position and alignment. The line keeps its frame and extruder, and only the gearbox changes.

We make the part rather than wait for it

Gear blanks, shafts, housings and adapters are machined in house, and our gear-cutting partner cuts the teeth. Worn housing bores are restored by line boring on our own equipment. If a component is no longer available, we measure the worn one and make a new one from it, the same way we handle reverse engineering on any other part.

Single-screw extruder gearbox after its overhaul, restored and repainted.

Twin-screw gearbox opened for inspection, gear train and bearings in the housing.

Gear train reassembled and re-timed before the case is closed.

Gearbox work on our bench

Inspection, housing bore repair and a finished rebuild from our shop. More photos and videos are in our gallery.

Helical gear stack removed from an extruder gearbox for measurement of tooth contact and journal diameters
Helical gear stack measured for tooth contact and journal size
Extruder gearbox housing with the output bearing bore during in-house line boring repair
Housing bearing bore during in-house line boring
Rebuilt extruder gearbox assembled and painted on a pallet at Zala Machine Co.
Rebuilt extruder gearbox, painted and on the pallet
02. Process

How a Zambello gearbox repair runs

Send us the nameplate, photos and a description of the fault, and we take it from there.

Call or email us with the nameplate, photos and a description of the fault.

The gearbox is shipped to our shop in Hillsborough, New Jersey.

The box is cleaned, stripped and measured. Gears, bearings, shafts, seals and housing bores are checked, and we report whether a repair or a new Zambello is the better answer.

Housing bores are line bored, worn parts are restored or made new, and modifications are machined. For a replacement, we supply the new Zambello and machine the adapter, floor risers or other modifications it needs to fit the line.

The box goes back together to its clearances. On twin-screws the gear train is re-timed, and runout, tooth contact and backlash are checked before the case is closed.

03. A recent job

A new Zambello on an old line

A blown film producer in California had an extruder gearbox that could no longer be supported. There were no parts and no replacement from the original maker, and the whole line was built around it.

A new Zambello heavy-duty single-screw gearbox replaced it, and we made everything it needed to fit the existing line. We machined a new gearbox-to-extruder adapter to connect the Zambello box to the extruder. We built floor risers that bolt to the existing floor mounts and carry the new gearbox at the right height and position. The customer kept the line and the extruder, and changed only the gearbox.

We take the same approach on any replacement. When a new Zambello does not fit the old footprint, we make the adapters, risers and modifications that let it fit.

04. Turnaround

How long it takes

Bearings and seals — 1 to 2 weeks.
A full rebuild — 6 to 10 weeks.

If gears have to be cut new, the job can run longer, and we tell you that when we quote rather than when it is late. If your line is down, say so on the call — see emergency machining.

05. Capacity

What we handle on a Zambello gearbox

The work that happens here, and the one step that goes to a partner.

Gearbox typesZambello single-screw and twin-screw extruder gearboxes, lab-scale to heavy-duty production
Housing line boringin house, to 20″ diameter over roughly 50″
Liftingto 10 tons
Made in housegear blanks, shafts, housings, adapters and mounting plates
Gear teethcut by our gear-cutting partner from blanks machined here
Checks on reassemblyrunout, tooth contact and backlash, among others
Turnaroundbearings and seals 1 to 2 weeks; a full rebuild 6 to 10 weeks
Replacementnew Zambello gearboxes, with adapters, floor risers and modifications machined to fit the existing line
06. Common questions

Zambello gearbox repair: common questions

Do you repair Zambello twin-screw gearboxes?

Yes. Twin-screw repair was the focus of Martin Zala’s training with Zambello in Italy. Shaft alignment and gear timing are checked and reset as the box goes back together.

How do I send you a Zambello gearbox?

Email the nameplate and photos to sales@zalamachine.com or use the quote form. We review it, and the gearbox is shipped to our shop for evaluation.

Should the gearbox be repaired or replaced?

We repair it when a repair makes sense. When it does not, we supply a new Zambello gearbox and machine whatever it needs to fit your existing line.

Can you fit a new Zambello gearbox to an existing line?

Yes. We machine the gearbox-to-extruder adapter, build floor risers that bolt to the existing floor mounts, and make any other modifications needed to set the new box at the right height, position and alignment. The line keeps its frame and extruder.

How long does a Zambello gearbox repair take?

Bearings and seals take 1 to 2 weeks. A full rebuild takes 6 to 10 weeks. It runs longer only if gears have to be cut new, and we say so when we quote.

What do you check before the gearbox goes back?

Runout, how the gears interact and their tooth contact, and backlash, among others. On twin-screws the gear train is re-timed and checked again before the case is closed.

Do you work on other gearboxes too?

Yes. We repair single-screw and twin-screw extruder gearboxes of other makes, and gear reducers and industrial gearboxes of every type. See extruder gearbox repair and industrial gearbox repair.

Send us the Zambello box, or the part that broke.

Email photos and the nameplate to sales@zalamachine.com or use the quote form. For other makes see extruder gearbox repair, and for the rest of our gearbox work see industrial gearbox repair.