Why round manhole cover win many project and customer's interest?
The manhole cover and wellhead are designed to be round because this can ensure that the size of the manhole cover in any direction is larger than that of the wellhead. If other shapes are square, the shape and angle of the manhole cover may fall from the wellhead (as shown in the figure). The red square indicates the manhole cover, and the black square indicates the wellhead. When the manhole cover is erected and deflected by 45 degrees, it will fall.)

All in all, round manhole cover is more safe than square in urban construction.
Zibo Best Energy-saving Materials Co., Ltd. was established in 2004, which is one of the largest composite manhole cover manufacturer in China, specializing in producing and supplying composite materials(SMC/BMC) manhole cover, rain-grating ,tree-grating, flower pot, fence and so on. Our products are strictly produced according to the BS EN124 and have obtained various kinds of certificates. Till now, our competitive products not only have good market in domestic, but also owned a large overseas market with a high reputation.
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