Contents
- 1 Where are stuffing boxes used?
- 2 Why is a stuffing box important?
- 3 How do stuffing boxes work?
- 4 How does a dripless stuffing box work?
- 5 How tight should a stuffing box be?
- 6 What is lamella in stuffing box?
- 7 When do I need to service my stuffing box?
- 8 Is the stuffing box the same as the packing box?
Where are stuffing boxes used?
A stuffing box or gland package is an assembly which is used to house a gland seal. It is used to prevent leakage of fluid, such as water or steam, between sliding or turning parts of machine elements.
Why is a stuffing box important?
If a pump handles suction lift and the pressure at the stuffing box is below atmospheric, the stuffing box function is to prevent air leakage into the pump. If the pressure is above atmospheric, the function is to prevent liquid leakage out of the pump.
When should I replace my stuffing box?
Finally, when the wear becomes excessive, the drip rate will increase when the engine is in gear and while the boat is at rest, requiring you to replace the packing. Some mechanics say you should replace the packing every other year, every two years, or every five years.
How many rings are in a box of stuffing?
Construction of a Diesel Engine Stuffing Box The housing generally consists of five ring grooves of which, the two uppermost grooves accommodate sealing rings to prevent blowing down of scavenge air along the piston rod.
How do stuffing boxes work?
All stuffing boxes work on the same basic principle: Rings of special wax-impregnated flax packing are wrapped snugly around the prop shaft and stuffed into a hollow packing nut that is screwed to the outside of the stuffing box housing.
How does a dripless stuffing box work?
Often referred to as dripless, face seals compress a fixed bearing against a collar that is attached to the shaft. A thin film of water forms on the interface between the stainless and the carbon, lubricating the seal. A hose connects the fixed bearing to the stern tube. This bellows should not contain any water.
What are the three main parts of stuffing box?
There are three main components to a traditional stuffing box: the stuffing box body, the compression sleeve, and some method of locking the compression sleeve in place.
How much should my stuffing box drip?
When properly adjusted, stuffing boxes are designed to “leak” slightly at two to three drops per minute while the engine is running and the shaft is turning. There should be no dripping when the boat is at rest and the shaft is not spinning.
How tight should a stuffing box be?
Most stuffing boxes are designed to accept three rings of packing. The joints should be oriented 120° apart from each other. The packing nut should be made snug, not much more than hand tight initially.
What is lamella in stuffing box?
Extensive service tests have shown that the lamella-type top scraper ring greatly reduces the number of oil filter backflushings. The scraper rings in the three lowermost grooves in the stuffing box minimise the system oil con- tent in the drain.
What is a stuffing box in oil and gas?
A Stuffing Box is a seal that is used to prevent fluids and gases from leaking between the turning or sliding parts of the machine elements. A general type of the Stuffing Box is the gland, which is used to shut rotating or reciprocating shafts.
How much should a stuffing box leak?
When do I need to service my stuffing box?
If your stuffing box leaks more than 8 or 10 drops a minute, it needs servicing. Tightening the stuffing box nut a half turn is all that is required to reduce the leak, but the location of the stuffing box can render this job far more difficult than it should be.
Is the stuffing box the same as the packing box?
Stuffing boxes are also called stuffing glands, packing glands or packing boxes but they are really all the same thing. For illustrative purposes I cleaned the stuffing box of it’s oxidation and grime with my a stainless wire brush.
What happens if you run a stuffing box with no water?
Over tightening of the packing-nut, and running the stuffing box with no water drips, will eventually wear a grove in the prop shaft and ruin it. It’s very important to allow a few drops of water per minute, when the shaft is spinning, for lubrication.
What does the stuffing box in a centrifugal pump do?
The hardware components within the Stuffing Box perform the important function of minimizing the leakage of “pumped up” process fluid out of the Stuffing Box; without Packing or a Mechanical Seal in the Stuffing Box, leakage would naturally occur since the rotating shaft pierces the Pump Casing.