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The design and preliminary performance of a multi layer metal cylinder head gasket with integrated 1.7mm diameter combustion pressure sensors is described. The pressure sensors are either removable from the gasket without need for engine head removal or permanently fixed to the gasket. The gasket design is suitable for all sizes and types of internal combustion engines including gasoline, diesel, or alternative fuel, with peak pressures ranging from 100bar to 350bar. The sensors’ diaphragms are positioned semi-flush with the gasket surface exposed to combustion gasses while the sensors’ sealing surfaces are located 5mm-7mm from the diaphragms. The devices miniature signal conditioners are mounted inside a gasket extension protruding beyond the engine block. The miniature fiber optic pressure sensor operates on the principle of light intensity changes transmitted by two fibers upon reflection from a metal diaphragm deflecting under the effect of cylinder pressure. Preliminary test results are reported here collected on a 4-cylinder gasoline engine demonstrating good agreement with a reference transducer. When optimized, it is expected that a gasket integrated sensor will offer the accuracy of +/-1.5% enabling advanced engine controls based on Indicated Mean Effective Pressure (IMEP), Mass Fraction Burned (MFB), Peak Pressure as well as control of pilot fuel injection and virtual Mass Air Flow and NOx sensing.

This paper discusses various methods for form machining of cylinder bores. One alternative is to use so-called torque plates. Torque plates are deformation elements with identical or similar deformation properties as the cylinder head together with the cylinder head gasket. With this deformation element, the cylinder block is clamped using the cylinder head bolts during the honing operation. Various designs of torque plates are presented here — torque plates which are already being used for serial production as well as newly developed, production optimised designs. As an alternative to the use of a torque plate, the kinematics of the honing procedure can be controlled. In this form honing method, not only static deformations but also dynamic and thermal deformations can be taken into account while producing the negative form.Copyright © 2007 by ASME

ABAQUS gasket elements are an efficient and flexible tool to study gasket applications. Nevertheless the usage of the ABAQUS gasket elements is not limited to gasket analysis, but it provides an effective improvement in structural analysis. The results point out that both the predicted contact pressure and the predicted stress distribution depend on the mesh topology. Several combinations of mesh dimension and topology are investigated. The purpose is the definition of a calculation methodology and the demonstration of the application potentiality. Complex models analysis highlights that the set methodology constitutes a very effective tool for the design and optimization of gasket, cylinder head and cylinder block. At last a particular case is studied and a structural improvement to resolve the problem of the low seal was obtained by FEM; the modifications were introduced in the layout and the test on the modified component confirmed the calculation previsions. The qualitative and quantitative indications provided by the calculation are confirmed by the experimental results, whether in condition of cold assembly (color film paper approach) or in condition of hot working (test to motor bench).

An improved diaphragm design for use with a gasket in a pressure vessel manway opening to prevent leakage of a pressurized fluid was developed by B&W Canada. The design was developed for high pressure typical of conditions in the primary side of a PWR steam generators. The sealing is achieved by a spiral-wound graphite filled gasket which is confined in a separate diaphragm groove. The diaphragm has an internal radial groove which uses strong spring back and the pressure of the fluid to increase and maintain the gasket seating load. As a result, this design provides a self-energizing joint which can accommodate changes in gasket contact pressure due to cover rotation, stud elongation and change in fluid pressure and temperature. Finite Element (FE) Analysis indicates that a more uniform distribution of gasket contact pressure along the radial gasket width is obtained and thus the sealing performance of the gasket is improved.Copyright © 2006 by ASME