A kind of high workability tire casting plaster powder and preparation technology thereof
Technical field
The present invention relates to a kind of high workability tire casting plaster powder and preparation technology thereof.
Background technology
At present, most of tire casting plaster die production producer is when making tire casting plaster mould, all directly use high strength gypsum (α-gypsum) powder to be starting material, be that 1:0.5~0.55 is mixed with water and carried out Mold Making by mass ratio, because the rare thick degree of gained calcium plaster is higher, its effective churning time has only 3min, flowing time 3~5min, presetting period 9min, final setting time 30min.In addition, utilize the obtained mould of above-mentioned α-terra alba, the coefficient of expansion is big, is about 0.5; Dry folding strength is low, for about 7MPa; Dry ultimate compression strength is also lower, about 22MPa.Because too short, effective churning time of material presetting period and flowing time are also shorter, particularly mobile relatively poor, not only caused certain limitation to operation, also be unfavorable for the finishing to obtained mould, especially owing to undercapacity, the work-ing life of mould is also lower.
Summary of the invention
The objective of the invention is to overcome the deficiencies in the prior art, a kind of existing long effective churning time and flowing time are provided, suitable presetting period and final setting time are arranged again, better mobile, and make product strength high high workability tire casting plaster powder and preparation technology thereof.
The objective of the invention is to be achieved through the following technical solutions:
The present invention's high workability tire casting plaster powder, raw material by following parts by weight is made: 100 parts of α-terra albas, 15~25 parts of white portland cements (preferred 20 parts), 0.5~1.5 part of sulfonated melamine compound resin (preferred 1 part), 1~3 part of peach gum (preferred 2 parts), 5~15 parts in sal epsom (preferred 10 parts).
The preparation technology of the present invention's high workability tire casting plaster powder at first takes by weighing each component raw material by above-mentioned weight proportion, places mixer to mix 20~30min each component raw material then.
In the described starting material: α-terra alba is main raw, white portland cement is toughener, sulfonated melamine compound resin is water reducer, also play toughener and sizing agent effect, peach gum is additive, existing sizing agent effect also has the retardant effect, and sal epsom works to strengthen the terra alba flowability.
Compare with existing α-terra alba, the present invention's high workability tire casting plaster powder, but not only having clear improvement aspect effective churning time flowing time, presetting period and the final setting time, good fluidity, and the intensity of obtained tire casting mould obviously improves, can reach present domestic tire enterprise fully to every technical parameter requirement of tire casting mould, wide accommodation, long service life; In addition, its starting material wide material sources, cheap, low cost of manufacture; Its preparation technology is simple, and easy handling is conducive to suitability for industrialized production.
Embodiment
The invention will be further described below in conjunction with embodiment.
Embodiment 1
The high workability tire casting plaster powder of present embodiment is made by the raw material of following parts by weight: 100 parts of α-terra albas, 15 parts of white portland cements, 0.5 part of sulfonated melamine compound resin, 1 part of peach gum, 5 parts in sal epsom.
Preparation: at first take by weighing each component raw material by above-mentioned weight proportion, then each component raw material is placed mixer mixing 25min.
Embodiment 2
The high workability tire casting plaster powder of present embodiment is made by the raw material of following parts by weight: 100 parts of α-terra albas, 20 parts of white portland cements, 1 part of sulfonated melamine compound resin, 2 parts of peach gums, 10 parts in sal epsom.
Its preparation technology is with embodiment 1.
Embodiment 3
The high workability tire casting plaster powder of present embodiment is made by the raw material of following parts by weight: 100 parts of α-terra albas, 25 parts of white portland cements, 1.5 parts of sulfonated melamine compound resins, 3 parts of peach gums, 15 parts in sal epsom.
Its preparation technology is with embodiment 1.
The using method of the described high workability tire of above-described embodiment 1-3 casting plaster powder:
Be that the ratio of 1:0.5 drops in the water with gained high workability tire casting plaster powder in mass ratio, soak 2min after, vacuum stirring 9min namely can be used for moulding; Mould is repaired after the initial set, treat the mould complete drying after, just can use.
Embodiment 1-3 gained high workability tire casting plaster powder and existing α-terra alba are made mould respectively as stated above, its effective churning time, flowing time, presetting period, final setting time are tested, and to its make the dry folding strength of product, dry ultimate compression strength is tested by QB/T 1640-1992, test result sees Table 1.
Table 1
? |
Embodiment 1 |
Embodiment 2 |
Embodiment 3 |
Existing α-terra alba |
Effective churning time (min) |
16min |
20min |
18min |
3min |
Flowing time (min) |
12min |
14min |
13min |
5min |
Presetting period (min) |
20min |
25min |
22min |
8min |
Final setting time (min) |
45min |
50min |
48min |
29min |
Dry folding strength (MPa) |
10MPa |
12MPa |
11MPa |
7MPa |
Dry ultimate compression strength (MPa) |
31MPa |
32MPa |
30MPa |
22MPa |
As shown in Table 1, the present invention's pottery strengthens tire casting plaster powder, compares with existing α-terra alba, is not only all having clear improvement aspect effective churning time, flowing time, presetting period and the final setting time, particularly flowing time; Dry folding strength and the dry ultimate compression strength of obtained mould obviously improve, thereby make the flowability of the present invention's pottery enhancing tire casting plaster powder and the intensity of obtained mould have remarkable advantages.