What parameters to focus on when choosing a hatch for an inspection well

The manhole hatch is designed for comfortable operation of utilities located underground. Various types of sewerage systems are equipped with such structures - from stormwater drainage to household fecal and industrial systems. They are needed to make the audit convenient for use and safe for others.

Device and scope

In contrast to the storm inlet equipped with a grate, the inspection hatches include a support ring and a cover. The structure of the main part is different and depends on the type of communication. Cast iron and polymer-sand elements are made with side protrusions that enter the neck grooves when installed. Plastic models are sometimes carved and equipped with folding handles.

The hatches perform the following functions:

• revision of the system node;
• preventing a person or animal from falling into the mine;
• ensuring the safety of transport movement;
• protection of underground utilities from water and debris;
• preventing the penetration of the sewer odor to the surface.

Thanks to the monolithic cover, foreign objects cannot enter the well shaft.

In urban areas, hatches are mainly installed in yards, on highways and pedestrian areas. The selection of the model depends on what kind of load the structure can withstand.

Characteristic features of different models

Hatches are subdivided according to configuration and material used. Usually they produce round products in the shape of wells, but the standards allow square lids. The latter, for example, include cast-iron hatches of the "Arbat" brand. And the design of the Empire hatch assumes a round lid, but framed by a frame in the form of a square.

Hatches are made of cast iron alloys, polymers and composite materials.

Cast iron products

The most common devices are made of this metal. Their main advantages are:

• high resistance to corrosion, temperature extremes and other negative external factors;
• difficulty with theft due to heaviness;
• the ability to withstand high loads - up to 90 tons.

Cast iron products are equipped with locks that can only be opened with a special tool. An additional protective measure helps to prevent illegal entry into well mines.

Metal products are produced only in accordance with the requirements of GOST 3634-99. They are divided into several types depending on weight and load indicators. The marking is indicated on the cover:

• "L" is a lightweight hatch with a load-bearing capacity of up to 1.5 tons and a weight of 65 kg. Placed in areas of pedestrian movement.
• "C" - middle hatch, holds up to 12.5 tons. Used in car parks, recreation areas and squares.
• "T" - heavy hatch with a maximum load of 25 tons, weighing up to 90 kg. Installed on highways with heavy traffic.
• "TM" - main hatch, holds over 40 tons. Product weight is about 100 kg. It is used in cargo car parks and high-speed highways.

There are super-heavy hatches that are installed at airfields, industrial enterprises and ports. The cost of products depends on the design and starts at 1400 rubles.

Polymer-sand constructions

Created from a composite based on polymer substances and sand.The polymer-sand hatch is suitable for different types of manholes and has many advantages:

• small weight, which allows you to mount devices without the use of special equipment;
• absolute resistance to rust and temperature fluctuations;
• easy opening and closing thanks to clever design.

Such hatches are frost-resistant. In them, unlike metal structures, with strong "minuses", the lid and the support ring do not stick together.

The cost of such hatches is less than that of cast iron. The price of the product starts from 700 rubles.

Another plus is the lack of interest on the part of attackers. It makes no sense to steal hatches from this material, they cannot be handed over to metal. But, in comparison with cast iron, composite is still a less durable material, and is not used in places with maximum load.

Plastic hatches

The lightest and cheapest, cost from 300 rubles, depending on the size. Polymer products are distinguished by a variety of shapes and colors, you can choose a suitable product for the architectural and design features of the backyard territory.

The advantages of plastic structures include:

• light weight, which simplifies the process of transportation and installation;
• anti-corrosion qualities and immunity to the negative influence of external factors;
• interchangeability;
• lack of interest among the kidnappers.

Polymer constructions are safe for the environment, do not emit toxic substances. They are relatively durable, capable of lasting up to half a century, although they cannot be compared with cast iron in terms of wear resistance. The products usually carry a load of up to 40 tons. It is not recommended to mount them on highways or in industrial areas.

Criterias of choice

When selecting products, they are guided by the withstand load and location, as well as the dimensions of cast-iron and composite manholes for inspection wells. The size range of plastic products is very diverse.

If hatches are selected for municipal and industrial needs, they must clearly comply with state standards in all respects. When choosing designs for a local area, you can order a product of any size and shape, but nevertheless, for long-term operation, its indicators should not differ much from standard ones.

Installation features

To install cast iron structures, you need to hire special equipment. Models made of composite and plastic materials can be assembled with your own hands. When arranging, it is necessary to ensure that the hatch does not rise above the level of the coverage, especially on the highway and pedestrian zone. Installation is carried out flush with the ground or asphalt.

Installation is carried out in four stages:

1. Mount the support ring on the reinforced concrete floor.
2. Pour concrete mixture for fixing.
3. Install the manhole cover in the ring after the concrete has set.
4. Holes are drilled in the body for fixing with anchors with subsequent fixing.

After the installation is completed, blind areas with a width of 1–1.5 m must be made in order to drain excess water.

For a longer service life of the hatches, it is necessary to periodically check them and clean them of contamination.

Modern models of well manholes provide reliable protection to underground networks and seamlessly integrate into any landscape.