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Selection of raw materials for cement pipes

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更新时间:2019年08月05日14:55:42 打印此页 关闭 Clicks: 279 Updated: August 5, 2019 14:55:42 Print this page Close
Cement pipes are widely used in various industries, and the selection of raw materials is very particular during production.

1.Sand

Generally, medium sand is used. The concrete has good workability and good anti-seepage function, while the concrete strength is low, and the pipe is easy to slump. The sand is thick, and the concrete has poor workability. The anti-seepage function is good, and the mixed strength is high. It is not easy to slump in the pipe, and the selection of the sand rate is also important. The sand rate is high, the concrete is easy to work with, the formability is good, the anti-seepage function is good, and the concrete in the pipe is easy to slump; the sand rate is low, the concrete and Poor performance, poor formability, poor impermeability, and concrete is not easy to slump in pipe making.

Stone

Cobble or broken pebble is used for small-diameter suspension roller tubes to reduce the frictional resistance of the stone surface, so that the concrete is compact and compact. Large-diameter suspension roller tubes should be machine crushed stone. The rough surface of the stones is easy to embed each other to reduce the concrete. Slumped can.

3.Cement

General Portland Cement No. 425 should be used. Due to the use of dry hard concrete for suspension rolls. Mixed ash is relatively small. Small change in dry shrinkage volume of cement. Due to the low amount of cement alone. Therefore, shortening cracks are generally not present. Because the initial setting time of the cement is relatively short. Early stage strength is high. Regarding the stability and density of concrete, preventing the inner wall from collapsing, there are advantages to steaming forward.
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