Sandvik / Tamrock
551 559 91 O-RING
DD320-40
| Part Number | 551 559 91 |
| Description | O-RING |
| Brand | Sandvik (Tamrock) |
| Assembly | CYLINDER ASSEMBLY |
| Type | Drill Rig Spare Part |
Quick answer
551 559 91 (also written 55155991, 551-559-91, or 551.559.91) is a Sandvik o-ring spare part used in the CYLINDER ASSEMBLY assembly of the Sandvik DD320-40. Verified compatible with 13 Sandvik machine models including DD320-40, DD321-40, DD321-40C. Available as an aftermarket replacement drill part from BK Drilling — Turkey-based Sandvik and Epiroc spare parts supplier serving mining contractors worldwide. Quote on request via WhatsApp; typical lead time 3-7 days for stock items.
Part code alternate forms: 55155991, 551 559 91, 551-559-91.
Compatible machines
13
OEM cross-reference
551 559 91
About Sandvik 551 559 91 O-RING
A precision-molded sealing element for the Sandvik DD320-40, this O-ring is used in the CYLINDER ASSEMBLY to create a reliable static or dynamic seal. Even minor O-ring deterioration can lead to system pressure loss, so scheduled replacement during routine maintenance is strongly recommended.
This is an OEM-compatible aftermarket replacement part for the Sandvik DD320-40 (DD320-40). Also compatible with Tamrock branded equipment of the same model series. BK Drilling supplies this part with fast worldwide shipping and competitive pricing.
Frequently asked questions
Why do O-rings fail in drilling equipment?
O-rings fail due to chemical degradation from hydraulic fluid, extreme temperature cycling, excessive pressure spikes, improper installation (twisting or pinching), and age-related hardening. Using the correct material compound for each application is critical.
