Double-acting mechanical seal with 35 mm shaft diameter for size 3 with reinforced drive homogenisers from Vakumix and NETZSCH Vakumix – suitable for plants with approx. 600 to 1,500 litres batch size and for circulation agitators in pre-phase vessels. Price: EUR 3,322.10 net (EUR 3,953.30 incl. 19% German VAT), plus shipping of EUR 49.95 per seal (insured express, Germany).
Delivery time approx. 1 week (dispatch after 3–7 working days). Sales exclusively to business customers.
Compatible – not an original part: This mechanical seal is a bought-in part from specialised seal manufacturers and fits homogenisers from NETZSCH Vakumix and Vakumix. It is not an original part and this is not an offer from NETZSCH or Vakumix.
Typical applications of the 35 mm seal
The 35 mm mechanical seal is intended for size 3 homogenisers with a reinforced drive – also in plants with batch sizes of around 600 to 1,500 litres. The stronger shaft differs from the standard drive (30 mm); the two seals are not interchangeable.
- Size 3 with reinforced drive, 600 to 1,500 litres
- Not interchangeable with the 30 mm seal
- Also suitable for circulation agitators with a 35 mm shaft
Technical data
| Feature | Mechanical seal 35 mm |
|---|---|
| Shaft Ø | 35 mm |
| Homogeniser size | Size 3 with reinforced drive |
| Batch size of the plant | Approx. 600 to 1,500 litres |
| Design | double-acting |
| Housing | V4A stainless steel |
| Seal rings | 4 × silicon carbide (SiC), alternatively e.g. carbon against chrome cast iron |
| O-rings | FKM, others e.g. EPDM on request |
| Suitable for | Homogenisers from Vakumix and NETZSCH Vakumix, circulation agitators in pre-phase vessels |
| Price | EUR 3,322.10 net · EUR 3,953.30 incl. 19% VAT |
| Delivery | delivery time approx. 1 week, insured express shipping within Germany EUR 49.95 per seal |
Why silicon carbide?
Silicon carbide (SiC) is particularly wear-resistant – even with abrasive raw materials. That is why the standard version uses four SiC seal rings. Other material pairings are possible for special applications.
Replace seal and shaft together
If the mechanical seal is leaking, the shaft should be checked too: with increasing age, imbalance can occur, and the shaft wears in the area of the seal. A new seal on an old shaft lasts much less long. We supply the matching shaft and fit both on request in our workshop in Weyhe or on site at your plant.
Service around your seal
- Damage analysis of every removed seal with a short report
- Testing after repair or fitting, on request with a test report
- Collection by courier and return delivery
- Exchange seal to avoid downtime
Frequently asked questions about the mechanical seal 35 mm
How do I recognise the reinforced drive with a 35 mm shaft?
The type plate, drive data and documentation give indications. The measured shaft diameter in the seal area is definitive: 35 mm instead of 30 mm. If in doubt, we check the fit from your photos.
Can I use a 30 mm seal instead of the 35 mm seal?
No. The seal must match the shaft diameter exactly. Only the 35 mm mechanical seal is suitable for a 35 mm shaft.
Should the shaft be replaced along with the 35 mm seal?
We recommend it: the shaft wears in the seal area, and imbalance can develop with age. A new seal on an old shaft lasts much less long.
Other sizes
Last updated: October 2026
All trademarks and product names mentioned, in particular Vakumix, NETZSCH, LambdaVita, KappaVita and GammaVita, are the property of their respective owners and are used solely to identify the products offered. This is not an offer from the manufacturer. SEEFRIED Verfahrenstechnik is an independent supplier and is not affiliated with these manufacturers; the mechanical seals offered are compatible spare parts, not original parts.