Roper Pump G4-112 Complete Buna Mechanical Seal for 3735 to 4758
The Roper G4-112 is a complete Buna mechanical seal for the large frame mechanically sealed 3600 Series pumps, covering the 3735 through 4758 range in the 35, 43, 48 and 58 displacement sizes. These are the high capacity machines in the family, and the seal that goes into one is physically larger, runs at a greater face diameter and therefore at a higher rubbing speed than the small frame equivalent.
That larger diameter is why installation discipline matters even more on the big frames. Face rubbing speed rises with diameter, so the heat the faces generate has to be carried away by the product film between them. Anything that interrupts that film, a starved suction, a pocket of vapor, a few seconds of running dry while a line fills, shows up as heat checking on the faces rather than as a gradual wear pattern. Bring the pump up with the suction flooded, vent the seal chamber, and avoid throttling the inlet to control flow. Fit the seal complete rather than swapping a single face onto an old seat, since matched lapping is part of what makes the pair seal.
Key Features
- Genuine Roper Pump Company mechanical seal, part number G4-112
- Sized for the large frame 3735 through 4758 mechanically sealed pumps
- Supplied complete with matched rotating assembly and stationary seat
- Buna elastomer for general purpose petroleum and oil service
- Keeps product leakage off the floor on high capacity transfer duty
Applications
- 3600 Series mechanically sealed pumps, 3735 through 4758
- High volume loading, unloading and cargo transfer
- Residual fuel oil, molasses and resin handling
- Refinery, terminal and process plant service
- Large frame pump overhaul and seal renewal
Specifications
- Brand: Roper Pump Company
- Part Number: G4-112
- Part Type: Mechanical seal, complete
- Elastomer: Buna
- Fits: 3600 Series 3735 through 4758
- Pump Family: Large frame 3600 Series, sizes 35 through 58 gallons per 100 revolutions
- Condition: New
Frequently Asked Questions
Q: Will the small frame seal fit if I am short of time?
No. The large frame seal runs on a bigger shaft and in a deeper chamber, and the 11 to 22 size seal simply will not locate correctly.
Q: Is a flush line needed on the large frames?
It depends on the product. Heated, dirty or vapor prone liquids benefit from a flush or a vent to keep the seal chamber full, while clean cool oil generally does not need one.
Q: Why do the faces come up heat checked?
Almost always a loss of the liquid film between them. Starved suction, entrained vapor and dry starts are the usual causes, and each leaves the same fine crazing across the face.
Q: Can I lap and reuse the old stationary seat?
It is not worth it in the field. Reclaiming a seat needs flatness measured in light bands, and a seat that is a fraction out defeats a new rotating face immediately.
Not sure this is the right part? Send us a Picture of the pump plate on your pump and the CLR Marine team will confirm the correct mechanical seal before you order.
CLRMarine
