Production control procedures
Creation of orthopedic mattresses is a complex multistage process, the result of which is a high quality product that provides a comfortable sleep. In the manufacture of mattresses, the production control is carried out from start to finish of the technological process.
To evaluate the characteristics of mattresses, the whole series of tests is carried out; this is softness, durability and shrinkage of the mattress control, spring and spring unit stiffness control, wire quality control, steel strip control, as well as polyurethane materials quality control. In order to produce a high-quality cover, the control of woven and nonwoven materials quality is carried out.
High-tech laboratory equipment with indication of error of 0.5% to 1% is used for quality control.
Softness is the ability of the mattress to deform under load. Physiologically, the feeling of mattress softness is the feeling of a certain amount of pressure that occurs as a mattress response to the impact of the applied load (person).
The essence of the method for determining the softness:
The test sample is placed on a horizontal surface. It is loaded with a special disc from 3 to 140 kg. The height to which deforms (bends) the test sample is the value of softness.
Mattress durability and shrinkage
Durability is the ability to resist for a long time the applied loads without failure. In other words, it is the number of turnovers made by the user for the time of operation. Shrinkage is a defect of the sleeper flatness.
The essence of the method for determining the durability and shrinkage:
The test sample is mounted on a test stand. Depending on the width of the test sample, checkpoints are determined. The initial height of each individual point is determined. A drum weighing 140 kg is put on the prepared sample. The drum has a barrel shape and the central part of the drum is cylindrical. The stand is turned on and the drum starts to rotate at a speed of 36 rev/min. One rotation of the drum simulates one rotation of the user on the mattress, and the number of rotations that the test sample can withstand without destruction is the life of the mattress.
The amount of load that affects the durability without destruction during the test corresponds to the maximum weight of the load, i.e. the reserve in kilograms that the mattress will stand.
We manufacture mattresses that withstand 29,000 cycles, which is approximately 10 years of reliable service. After removing the load, the amount of deformation (deflection) of each individual point is measured. The difference of the deflection height before and after the test is the shrinkage of the test sample. On mattresses produced by us the shrinkage for 10 years of service does not exceed 30 mm.
Before making a spring, the wire passes through the stage of control.
To determine the tensile strength, the sample is subjected to tension under the influence of gradually increasing force. The greatest effort prior to destruction of the sample is taken for the effort corresponding to the tensile strength.
Stiffness of the spring block
Stiffness is the ability of the spring block to resist the action of the load.
The test involves the calculation of the static load that causes compression of the spring unit until the connection of the supporting coils.
Stiffness is the ability of the spring to resist the action of the load.
The test involves the calculation of the static load that causes compression of the spring until the connection of the supporting coils.