Rings For Four-Stroke Engines
We are world-beaters when it comes to fast turnaround and speedy, reliable delivery, usually from stock, to any destination.
SPR is recognised as one of the world's largest suppliers of piston rings for diesel engines.
There is no doubt piston rings from SPR offer the finest quality available in the world today. For a piston ring supplier who can offer total quality, reliability and service, turn to SPR.
Of course, the major engine differentiation is between 2-stroke and 4-stroke cycle specification but cylinder bore and engine RPM are also very important influences on the pattern of the piston ring pack.
Four stroke diesel engines are used for both marine and locomotive propulsion as well as power generation. These pistons should contain 4-5 rings, often three sealing rings with profiled faces and hard coatings and two scraper rings.
SPR "A" CATEGORY ENGINES - 4-stroke
Engine types for which rings are usually in stock.
This is not an exhaustive list of SPR's products.
| DESIGNER | SERIES | MODEL |
| ABC | 9.1/2 in | DXC |
| ALLEN | 9.1/2 in | BCS/DX/D |
| B&W | 20MTBHB30 | |
| B&W | T23 | HH |
| B&W | T23 | LH |
| B&W | V/L/T | V23/L23/T23 |
| B&W | T/V | T23/V23 |
| B&W | 23/30 | L |
| B&W | 26MTBH40 | |
| B&W | 28/32 | L |
| CREPELLE | 260 | 8-SN2 |
| DAIHATSU | PSHT | 26D/26H |
| MAK | 451/452/453 | MU/AK |
| MAN | 23.5/33 | GV |
| MAN | 25/30 | ASL |
| MAN | 40/54 | VV |
| MAN | 40/54 | A |
| MIRRLESS | 8.3/4 in | ESMA/ETSL/ESL |
| PIELSTICK | PC2V | |
| PIELSTICK | PC2.2 | |
| PIELSTICK | PC2.5 | |
| PIELSTICK | PC2.6 | |
| PIELSTICK | PC3 | |
| RUSTON PAXMAN | 8" | 6AP2Z |
| RUSTON | 12--16 | RK3C |
| SULZER | 20/24 | AL |
| SULZER | 22 | BAH |
| SULZER | 25--25/30 | AL/AV/ASV |
| SULZER | 25 | AS/AT |
| SULZER | 40S | ZAV |
| SULZER | 40/48 | Z |
| WARTSILA | R22 | HFD |
| WARTSILA | 240--514 | TK |
| WARTSILA | 424--624 | TS |
| YANMAR | 170mm | RL-HT |
| YANMAR | 200mm | UL-UT |
| YANMAR | 240mm | GL-UT |
A flick through the product catalogue of any major piston ring manufacturer
will reveal a bewildering spectrum of styles and finishes. This list
summarises the most common types of ring used in today's engines and
explains the rationale behind the designs.
Every piston ring is designed with a particular purpose in mind, although
their functions fall into two broad categories. Firstly, to effectively
seal the combustion chamber in order to maintain pressure and optimise
energy output; secondly, to control lubrication oil consumption for
the smooth operation and extended service life of moving components.
Sealing rings are known collectively as "compression rings" and oil
distribution rings as "oil control rings". Some rings, however, are
designed to perform both functions and therefore do not fit neatly into
either of the two categories.
So ring geometry is a crucial part of determining the rings' functional
characteristics and combined with SPR's mastery of choosing and using the
most appropriate base materials and surface treatments has created a range
comprising a "ring for all engines".