Curing Of Concrete Pipes Made By Vertical Concrete Pipe Machine
Concrete curing is the significant process to guarantee the hardness of concrete and one of the important factor that affects the duration and physical properties. The different curing process can be used according to the different season and environment. Traditional concrete pipe machine like roller suspension machine and centrifugal pipe machine use steam curing, vertical concrete pipe machine could use both natural curing and steam curing.
The header should be used to protect the joint of pipes made by vertical concrete pipe machine during the curing process, the header can prevent the joint go deformed and guarantee the accuracy of dimension.
The pipes are cured vertically on the ground after production, if the ground is not even enough, the wet pipes can go slope easily. In case of that situation, the unevenness of the ground should no more than 2mm. clean the cement or concrete scraps that might affect the evenness of the ground. Broken or deformation may happen when demould on the uneven ground.
Natural curing is widely used in regular production, but for mass production in urgent orders, steam curing is the best way to shorten the curing period.
Natural curing is commonly used in vertical concrete pipe machine production. Use the plastic film cover the surface of the finished pipe, the hydration heat generated by cement could cure concrete pipes in good, the usage of plastic film prevents the appearance of the cracks too.
Some of the factories use the plastic cover, GRP cover or the thermal insulation material cover to build a shelter. The purpose is to prevent the water from steaming and keep the heat, use the hydration heat to cure the concrete pipes.
Steam curing. There are four stages during the steam heat curing. Pre-curing, heat curing, constant temperature curing and the cooling curing.
The pre-curing is to improve the hydration degree before steam curing, the concrete acquires certain structure strength.
The heat curing speeds up the hydration, improve the density of concrete, form the structure of concrete.
The constant temperature curing period is the significant process to improve the strength of concrete.
The cooling curing is the period that cools the high temperature to the normal temperature.
According to the standard, the pre-curing should no less than 2 hours, heat-up speed should no more than 25℃/h during the heat curing period, cooling speed should no more than 20℃/h during the cooling curing. The constant temperature curing should no more than 65℃.
The detailed specification should adjust according to the practical situation.