The role of anti -Soviet hatches 

The role of anti -Soviet hatches

1. Design features

Anti -additive hatches have the following technical characteristics:

-Material: High-strength cast iron with spherical graphite Qt500-7

- enhanced rib of stiffness (thickness ≥15 mm)

-3-point blocking system (carrying capacity ≥400 kN)

-polymer seal (temperature range -40 ℃ ~+120 ℃)

2. The principle of action

1) load distribution

An increase in the area of ​​the support by 35% allows you to reduce the voltage in the asphalt coating by 62% at a load of 100 kN.

2) control of displacements

The flange structure with a gap ≤1.5 mm and anchor bolts (preliminary tension 50 kN) limits vertical movements up to 0.5 mm.

3) temperature compensation

Elastic seal (constant deformation ≤8%) provides compensation for temperature deformations up to 3 mm.

3. Advantages

- service life: 30 years

- decrease in the frequency of repairs by 80%

- retroreflecting coefficient:> 450 MKD/LC/m²

4. Practical application

On the runway of Pudun Airport (Shanghai), the use of anti-"hatches allowed:

- improve the IRI evenness index from 3.2 to 1.8 m/km

- limit the siege of coating up to 1.2 mm

- comply with the ICAO 4E standard