Excavator quick couplers

How to choose

A quick coupler sits between the stick and the attachment, so it decides how fast an operator changes from a digging bucket to a grading bucket and how firmly that attachment is held while the machine works. Sieruta builds couplers in Ostrołęka, Poland, for the interfaces a European contractor actually meets: the Scandinavian S standard, the CW system common in the Netherlands and Belgium, the cast MS and SY systems, and pin grabbers that pick up the excavator maker's own brackets. Each system comes in three operating types: fully hydraulic automatic, mechanical by wrench, and hydraulic tilt and swivel with two times 90 degrees of movement. Sizes run from carriers under 1 t up to 45 t machines. Choose the system your attachments already carry, then the size band for the carrier, then the operating type for how often you swap during a shift.

1. 1

   Start from the brackets you already own

   The coupler has to match the brackets welded on your buckets, not the other way round. Read the system name off one bucket bracket, or send us a photo and the pin dimensions, and we will tell you which family fits before anything is ordered.

2. 2

   Match the size to the carrier weight

   Every coupler family runs in size steps, and each step names the excavator weight band it was drawn for. An undersized coupler can be overloaded and must not be used outside its rated carrier range. A coupler one size too large adds mass and length you carry all day for nothing.

3. 3

   Decide mechanical, automatic or tilt and swivel

   A mechanical coupler is opened with a wrench and costs least; a fully hydraulic one is opened from the cab and pays back on sites where you change attachment several times an hour; a tilt and swivel version angles the attachment hydraulically through 2 × 90°. It covers many angled jobs without a separate tiltrotator, but it does not rotate continuously through 360°.

4. 4

   Check what the machine can feed

   A hydraulic coupler needs a spare double-acting line and a control in the cab, and a tilt and swivel version needs a second one. If the carrier has only one auxiliary circuit, say so on the quote form and we will propose the version it can run.

5. 5

   Check the safety features before the price

   The locks differ by coupler system, and each family page lists its mechanical and hydraulic locking features. Before you compare prices, check which locks are listed for the coupler you plan to buy.

Questions we are asked

Which coupler system should I order?

Order the one your attachments already use. S system is the Nordic standard, CW is widespread in the Netherlands and Belgium, MS and SY are common in central Europe, and a pin grabber takes the excavator maker's own brackets.

Can I keep my existing buckets?

Usually yes. If the buckets carry brackets of the same system and size, they go straight on. If they are direct fit on pins, a pin grabber coupler takes them, or we can fit new brackets to them.

What does a coupler change on the machine?

It adds length between the stick and the attachment and it adds mass, so breakout force and lifting capacity drop a little. The dimensions and the mass of every model are printed in the table on each family page.

Do I need extra hydraulic lines for a tilt and swivel coupler?

Yes. A tilt and swivel coupler needs its own hydraulic supply beside the line that locks the coupler, so the carrier needs two auxiliary circuits or a valve block that splits one.

Can one coupler take attachments from different makes?

A pin grabber with variable pin centres takes several different original brackets, which is the usual answer for a mixed fleet. Tell us the makes and models you run and we will confirm the sizes before you order.