The production technology of cast iron well cover is mature and easy to place. The well cover of any specification only needs to drill two holes as required to be equipped with the anti-theft device. If the well cover is newly made, two holes shall be reserved as required during casting, and the anti-theft device can be installed.

The security and reliability of the anti-theft well cover are very high. With the well cover of the anti-theft device, the firmness and opening of the well cover must be kept by a special person, which can be completed in a few seconds.

It has strong impact resistance, anti sawing, anti prying, anti drilling and other effects, and nothing else can open it; It has good anti freezing and anti rust effects.

In the past road construction, if the old well cover was installed, the backfill around the well ring could not be rolled by the road roller, and the compactness could not meet the specification requirements. Passing cars always vibrate the well cover. Over time, there will be local settlement and cracks around the well ring, just like black circles all over the road. It is not only unsightly, but also the driver will suffer from bumps when driving. The third generation began to adopt a variety of new technologies and processes, with five functions of anti noise, anti-skid, anti-theft, anti fall and anti displacement, which fundamentally solved this problem. The well ring adopts the structure form of ring to ring connection. Through riveting with the embedded bolts on the precast concrete shaft, the well ring displacement caused by rolling during construction is avoided, the rolling compactness around the well ring is ensured, and the inlaid wear resistance coefficient is increased. The road around the well ring will no longer sink, and the “black eye” will disappear.

In addition, a cassette opening folded plate is also set under the well ring to replace the original anti-theft iron chain, solve the rust problem of the anti-theft iron chain caused by sewage and gas, and make the anti-theft function more perfect. At the same time, a T-shaped rubber ring with a thickness of 1 cm is embedded in the well ring mouth to increase the contact area and effectively prevent the sliding vibration of the well cover.

Inspection of cast iron manhole covers

Appearance: no obvious casting defects, clear pattern and clear handwriting.

Flatness inspection: check the flatness of well cover with special mould. Make a mould with a diameter of product size and a depth of 37mm. The above dimensions are machined and the well cover is placed on the mould

The well cover shall not be higher than the mould, the depth (37mm) and the fit clearance shall be 3mm.

Sampling inspection is adopted for bearing load. The pressure test shall be conducted on the press, and the pressure of the well cover shall be 360kn or 210kN, and the qualified batch shall be confirmed.

Inspection for cast iron well cover and well ring: appearance: no obvious casting defects. Use special tools to detect the diameter of the well ring. The control range is the size of the well cover and the depth is 40mm. The bolt holes shall be inspected one by one with special inspection tools.

Matching and painting inspection: the T-shaped rubber ring shall be matched with the well ring. The rubber ring shall be placed flat in the T-shaped groove, not too long or too short, firmly bonded, and the matching gap shall not be greater than 1mm. The well cover and well frame shall be assembled flat without shaking and silent sound, and the height of the cover and frame shall not exceed 1mm. The T-shaped rubber ring shall be firmly adhered before painting. The well cover (ring) shall be painted evenly without rust.

As for the well ring of the inspection well, the T-shaped rubber strip is placed in the inner ring opening groove to form a rubber ring, which prevents the running, jumping and sound of the inspection well cover, increases the surface area between the well cover and the inner bearing ring opening, and increases the contact and coincidence area, so as to eliminate the running, jumping and sound of the well cover. In order to prevent the displacement of the wellhead of the inspection well, three 120 degree bolt fixing points are set on the outer ring of the inspection well. Through riveting with the embedded bolts, the displacement of the well ring caused by rolling during road construction can be avoided and the anti-theft performance of the well ring is improved. The surface of the manhole cover adopts cross flower edge triangular pattern, which can effectively play an anti-skid role.