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Published in Samuel C. Sugarman, HVAC Fundamentals, 2020
stuffing box: (Pump) A stuffing box seal has a “packing” which has rings made of graphite-impregnated cord, molded lead foil or some other resilient material formed into fitted split rings. These packing rings are compressed into the stuffing box by a packing gland. The tension on the packing gland is critical to the proper operation of the pump. If a packing gland must be replaced, consult the manufacturer’s published data for tension recommendations. If there is too much tension the proper water leakage will not occur and this will cause scoring of the shaft and overheating of the packing. Another problem is that as the seal gets older and the packing gland has been tightened over time the packing becomes compressed and loses its resiliency, overheating the stuffing box. When the packing gland is backed off to allow cooler operation there is excessive leakage. When this happens replace the packing.
Terminology and Concepts
Published in Heinz K. Müller, Bernard S. Nau, Fluid Sealing Technology, 2019
Heinz K. Müller, Bernard S. Nau
To ensure these functions, even if additional loading is supplied by fluid pressure, a preloading force must be designed into the seal, Fig. 7. For this purpose, mechanical seals are equipped with compression springs (a) or a bellows, which also acts as a spring. Elastomeric seals can be preloaded by the combined effect of dimensional interference and elastic deformation of the seal itself (b). Soft packing rings in a gland (“stuffing box”) is precompressed axially and relies on the Poisson effect to produce lateral expansion and hence a closing force acting on the sealing interface.
Seals
Published in J. T. McGuire, Pumps for Chemical Processing, 2020
The shaft to be sealed is surrounded by an annular region known generally as a “stuffing box”; see Fig. 11.9. Soft packing, usually in separate rings, is installed in the stuffing box, then compressed axially with a gland to produce a very close radial clearance between the shaft and packing. Packed box seals must have some leakage between the shaft and packing to lubricate the seal and to remove the small amount of heat generated.
Simulation Analysis and Experimental Verification of Tribodynamics of Reciprocating Friction Pairs in Low-Speed Marine Engines
Published in Tribology Transactions, 2023
Xianghui Meng, Rui Li, Youbai Xie, Chuanjuan Wang
Internal combustion engine is a typical multibody dynamics system. Many scholars have discussed its dynamic modeling method. It mainly includes rigid body dynamics modeling method and flexible body dynamics modeling method. In the previous dynamics research, scholars paid more attention to engine vibration, noise, and torsional vibration (7–9), while the contact and friction forces of friction pairs were often simplified. In recent years, with the improvement of numerical calculation ability, the research on modeling and simulation of lubrication of friction pairs and its coupling with dynamics began to increase (10–13). Abanteriba (14–16) carried out the early theoretical research on the crosshead slipper–guide friction pair. He established a simplified tribological analysis model based on the Reynolds equation and predicted the friction loss of the crosshead slipper. In recent years, Li et al. have done a series of works on the tribodynamics of the crosshead slipper. They presented a tribodynamics model for the crosshead slipper coupling its accurate dynamics and tribology. Based on the proposed model, they explored the influence of various design parameters of the crosshead slipper, which provided theoretical support for the low friction design of the crosshead slipper (13, 17, 18). For the piston rod–stuffing box friction pair, the related reports are very limited. Li et al. first established its tribological simulation model, which can predict the tribological characteristics such as friction force and oil film thickness (19).