Quality control of machine-made sand products
The quality indicators of machine-made sand mainly include particle gradation (fineness modulus), mud content, stone powder content (including methylene blue test), moisture content and crushing indicators, etc. According to the requirements of these indicators, it can be selected from raw materials and equipment. Control the quality of machine-made sand to make the quality reach the standard or even better.
1. Selection of raw materials for sand making
When producing machine-made sand, there are requirements for the raw materials:
① The compressive strength of the sand-making raw materials is ≥80Mpa, and there should be no potential alkali-active aggregate reaction. It is better to use clean, hard and non-soft granular raw materials to make the crushing index meet the standard.
② In the selection of mines, avoid using mines with thick overburden soil, more mud in the interlayer, and stratified rocks to control the mud content.
③Select raw materials with exposed rock formations. If they cover soil layers or contain weathered layers, they should be removed in time.
According to the above requirements, it is recommended to use cobblestone, river pebbles, limestone, granite and other stones with stable properties and up to standard hardness. The large stock is easy to mine, the mining cost is low, and the quality of sand making is good.
2. Select sand making equipment
The finished sand is made by a sand making machine. Choosing the right sand making machine can make the sand making effect more effective. It is recommended to use the HVI impact sand making machine, which has low dust pollution and low noise. It has both sand making and shaping functions. The granularity is adjustable, and the finished sand grains are round and uniform, which can reach the standard of grade I machine-made sand. During production, the feed size should be controlled at about 20mm. At this time, the sand quality of the impact sand making machine is better.
It is also necessary to equip a sand washer to transfer the sand to the sand washer for cleaning to reduce the powder content and control it between 3% and 7%. After cleaning, a combination of dewatering sieve dehydration and natural storage dewatering can be used to remove water content. The rate is controlled at 3%-5%. After this operation, high-quality machine-made sand can be obtained.
Phone: +86 17719851781
whatsapp: +86 17719851781