Hyundai Kia MS341-19 Engine Compartment Sound Absorbing Material Specification

The standard "Hyundai Kia MS341-19 Specification for Sound-Absorbing Materials in Engine Compartments," developed by Hyundai-Kia Motors, specifies the requirements for the use of soft felts for sound absorption or insulation. Soft felts are flexible insulation materials for high-temperature applications in inert or vacuum atmospheres and are composed entirely of carbon fibers. The felt's stability is determined during the initial production step, the needle-punching process, and continues throughout all subsequent high-temperature steps.

This standard is typically used as a floor carpet absorbent felt or as specified on the engineering drawing.

Parts using this material must comply with all requirements of the relevant assembly performance specification. The chemical composition and processing conditions must not be inappropriately altered, which could affect the quality of the parts. Before changing the chemical composition of the material, consultation with the materials and quality control departments is mandatory. The felt must be free of any odor that could cause an unpleasant sensation. Sound absorbers and coverings must be shaped and free of defects such as cracks, wrinkles, etc., unless otherwise specified.

This material must be tested by the methods specified in this standard and must conform to the requirements specified in the table entitled "Requirements." Samples must be produced by the same process as the parts.

Standard laboratory conditions are a temperature of 23 degrees plus/minus 2 degrees and a relative humidity of 50 percent plus/minus 5 percent.

All tests are carried out on samples at least 48 hours after molding and immediately thereafter, under specified standard conditions, with a conditioning period of at least 24 hours.

The Hyundai Kia MS341-19 standard describes the following test methods:

• Weight: Samples are prepared with dimensions of 300 mm x 300 mm. After weighing, the average weight is reported in grams per square meter. At least five test samples should be used, and the average values ​​should be reported.
• Thickness: A 100 x 100 μm specimen is placed horizontally on an anvil. A 120 x 120 μm steel platen weighing 150 g is placed on the specimen. After ten seconds, the specimen thickness is measured using a caliper. At least five test specimens should be used, and the average values ​​should be reported.
• Tensile strength: Must comply with MS200-41 standard. However, the sample must be sampled as dumbbell type 1 in the MD and AMD directions of the product, respectively. Tensile speed must be 200 μm/min. Test conditions: Temperature: 80 degrees Celsius plus/minus 2 degrees Celsius x 50 hours, humidity: 50 degrees Celsius plus/minus 2 degrees Celsius, 95% relative humidity x 336 hours. At least 5 test samples must be used, and average values ​​must be reported.
• Shrinkage: A 150 x 150 μm sample, marked in the center with a 100 x 100 μm mark, is prepared. The sample is placed in a thermostatic chamber under the following test conditions. The sample is then held for 60 minutes under standard laboratory conditions. Shrinkage in the longitudinal and width directions is measured. Test conditions: Temperature: 80°C (plus/minus 2°C) for 50 hours; Humidity: 50°C (plus/minus 2°C) for 95% relative humidity for 336 hours. At least 5 test samples must be used, and the average values ​​must be reported.
• Water absorption: Samples measuring 100 mm x 100 mm are placed horizontally in a temperature and humidity control oven at 40°C plus/minus 2°C and 95% relative humidity for 16 hours. The sample is removed from the oven, and any moisture on the sample is wiped off with a paper towel. The water absorption rate is then measured. However, post-absorption weight measurements must be made within 5 minutes of removing the samples from the oven. At least 5 test samples must be used, and the average values ​​must be reported.
• Odor: Must comply with MS300-34 standard.
• Compressive strength ratio: Specimens with dimensions of 100 x 100 Φ are prepared. The specimen is placed between steel panels with a thickness of 100 x 100 x 0,8 Φ. A 500 g (40 Φ) weight is then placed in the center of the specimen. The specimen is held under the following conditions. The weight and steel panel are then removed, and the compressive strength ratio is measured after 1 hour of exposure under standard laboratory conditions. At least five test specimens must be used, and the average values ​​must be reported.

This standard also defines the following test methods:

• Sound absorption coefficient
• Compression stress
• Mold
• Flammability
• Thermal cycle
• misting
• Peel strength
• Cold impact resistance
• Heat loss and heat shrinkage
• Loss of sound transmission

In a highly regulated field of automotive engineering, material and component standards like the Hyundai Kia MS341-19 are essential for ensuring the durability, safety, and efficiency of vehicle systems. The Hyundai Kia MS341-19 standard specifically addresses acoustic management components, particularly sound absorbers designed for the engine compartments of Hyundai and Kia vehicles. This standard ensures that these materials reduce noise, vibration, and harshness while withstanding extreme thermal and environmental stresses.

In short, the Hyundai Kia MS341-19 standard stands as a testament to the group's engineering prowess, transforming engine noise from a nuisance to a manageable element of the driving experience. Thanks to high-performance sound absorbers, it enhances vehicle quality while supporting broader goals such as safety and sustainability. Owners benefit from quieter rides and longer-lasting components, which have led to Hyundai and Kia models being highlighted in customer satisfaction surveys.

Our organization, with its competent and experienced team, has been understanding the needs of its customers for years, providing them with the advanced testing services they need, and assisting them in the establishment, implementation, and improvement of management systems. In this context, we also provide testing services in accordance with the "Hyundai Kia MS341-19 Specification for Sound Absorbing Materials in Engine Compartments" standard.