CN212945325U

CN212945325U - Sand mold cavity of large casting

Info

Publication number: CN212945325U
Application number: CN202021835967.9U
Authority: CN
Inventors: 罗永扬; 王忠福; 申波; 张艳明; 许占良; 袁自贞
Original assignee: Xinxiang Changcheng Cast Steel Co ltd
Current assignee: Xinxiang Changcheng Cast Steel Co ltd
Priority date: 2020-08-28
Filing date: 2020-08-28
Publication date: 2021-04-13
Anticipated expiration: 2030-08-28

Abstract

The utility model discloses a sand mould cavity of a large casting, wherein a main core rod of the sand mould cavity is of a hollow tubular structure, and a pipe cavity of the main core rod is communicated with an exhaust hole on a face box of the sand mould cavity; the pipe wall of the main core rod is provided with a plurality of ventilation through holes, and the outer wall of the main core rod is wound with a ventilation material. The utility model discloses a sand mould die cavity of large casting sets up main core bone into hollow tubular structure, sets up ventilative through-hole on its pipe wall to twine ventilative material on its outer wall, when the pouring, the gas that produces in the die cavity collects to main core bone through ventilative material, spills over the back by ventilative through-hole to the pipe cavity and discharges through the exhaust hole, has effectively avoided the die cavity in the molten steel to roll, has changed the fire phenomenon, has guaranteed large casting quality.

Description

Sand mold cavity of large casting

Technical Field

The utility model belongs to the casting field especially relates to a sand mould die cavity of large casting.

Background

The large steel casting is cast by a sand mould cavity formed by combining an appearance core and an inner cavity core, and the effective air introduction and exhaust of the sand mould cavity are critical in the casting process. Unsmooth exhaust can cause the cavity to be suffocated in the pouring process, and the serious possibility of causing the molten steel poured into the cavity to roll or splash, so that the casting becomes honeycomb and is scrapped. Although gaps among the molding sand in the cavity can be ventilated, for the casting of large castings, the core of the inner cavity is large, more gas is generated during pouring, the air cannot be effectively and quickly exhausted only by the gaps among the molding sand, and the quality of the castings can be influenced by the untimely exhaust.

SUMMERY OF THE UTILITY MODEL

The utility model aims at providing a sand mould die cavity of large casting can in time effectively exhaust when large casting is cast, improves the casting quality of large casting.

The technical scheme of the utility model is that:

a main core bar of the sand mould cavity is of a hollow tubular structure, and a pipe cavity of the main core bar is communicated with an exhaust hole on a face box of the sand mould cavity; the pipe wall of the main core rod is provided with a plurality of ventilation through holes, and the outer wall of the main core rod is wound with a ventilation material.

Preferably, the main core is a steel pipe, the diameter of the steel pipe is 80-300m, and the wall thickness of the steel pipe is 4-20 mm.

Preferably, the winding thickness of the breathable material is 20-80 mm.

Preferably, the breathable material is breathable rope.

Preferably, the breathable rope is a straw rope or a plastic rope.

Preferably, the ventilation through holes are round holes or oblong holes.

The utility model has the advantages that:

the utility model discloses a sand mould die cavity of large-scale foundry goods sets up the main core bone into hollow tubular structure, sets up ventilative through-hole on its pipe wall to twine ventilative material on its outer wall. When a large casting is poured, when gas generated in the cavity is collected to the position near the main core rod, due to the permeability of the permeable material, the gas can be collected to the main core rod through the permeable material outside the main core rod which is longitudinally arranged, overflows into the pipe cavity through the permeable through hole on the main core rod, and then is discharged through the exhaust hole. Because the air-permeable material is wound on the outer wall of the main core rod, the gas in the whole sand model cavity can be effectively collected and discharged in time, the path of the gas discharged out of the cavity is greatly shortened, the resistance in the gas discharge process is reduced, the phenomena of gas holding and cavity molten steel rolling and burning during pouring are effectively avoided, the pouring process of the large casting is stable in filling, and the quality of the large casting is ensured.

Drawings

Fig. 1 is the structural schematic diagram of the sand mold cavity of the large casting of the utility model.

In the figure: 1. an exhaust hole; 2. a sand mold cavity; 3. molding sand; 4. a breathable material; 5. a main core rod; 6. and (7) a ventilation through hole.

Detailed Description

The present invention will be described in detail with reference to the accompanying drawings.

Fig. 1 is a schematic structural view of a sand mold cavity of a large casting according to the present invention, as shown in fig. 1, a main core rod 5 of a sand mold cavity 2 of a large casting according to the present invention is a hollow tubular structure, and a tube cavity of the main core rod 5 is communicated with an exhaust hole 1 on a face box of the sand mold cavity 2; the pipe wall of the main core rod 5 is provided with a plurality of ventilation through holes 6, and the outer wall of the main core rod 5 is wound with a ventilation material 4.

The utility model discloses a sand mould die cavity of large-scale foundry goods uses hollow tubular structure to do main core bone 5 when making the core to set up a plurality of ventilative through-holes 6 on main core bone 5. Before the main core 5 is put into a core box for core making, the outer wall of the main core 5 is firstly wound with the air-permeable material 4, then the main core 5 wound with the air-permeable material 4 is put into the core box for core making, then the molding sand 3 is filled in, and the core is made after tamping and hardening. Then, molding and matching are carried out, the core is placed into a manufactured sand mold cavity 2, and the vent holes 1 on the surface box are correspondingly communicated with the vent through holes 6, so that the sand mold of the large casting is manufactured. In the pouring process, the smelted molten steel is poured into the sand mold cavity 2 through a pouring system, at the moment, the moisture of the molding sand 3 in the core is changed into gas through the high-temperature action of the molten steel, the gas is led to and discharged into the tube cavity of the main core bone 5 through the gas permeable material 4 and the gas vent 6, and finally the gas generated in the pouring process is led to and discharged out of the sand mold cavity 2 through the exhaust hole 1 of the face box, so that the smooth pouring of large castings is ensured, the phenomena of cavity molten steel rolling and fire hazard caused by unsmooth exhaust in the pouring process of the large castings are effectively avoided, and the quality of products is ensured.

The utility model discloses a sand mould die cavity of large casting sets up main core bone into hollow tubular structure, sets up ventilative through-hole on its pipe wall to twine ventilative material on its outer wall, when large casting pouring, when the gas that produces in the die cavity collects near main core bone, because ventilative material's gas permeability, gas can collect to main core bone through the outer ventilative material of the main core bone of vertical setting, spills over to the pipe cavity through the ventilative through-hole on the main core bone, thereby discharges through the exhaust hole. Because the air-permeable material is wound on the outer wall of the main core rod, the gas in the whole sand model cavity can be effectively collected and discharged in time, the path for discharging the gas in the cavity is greatly shortened, the resistance in the gas discharging process is reduced, the phenomena of gas holding and cavity molten steel rolling and fire burning during pouring are effectively avoided, the pouring process of the large casting is stable in filling, and the quality of the large casting is ensured.

The main core rod can be a metal pipe, preferably a steel pipe, and the steel pipe is convenient to obtain materials and low in price. Plain carbon steel can be used as the steel pipe, and the diameter of the steel pipe is preferably 80-300m and the wall thickness is preferably 4-20 mm. Too thin steel pipe is not enough in strength and cannot play the role of the main core, and too thick steel pipe is high in cost.

Preferably, the winding thickness of the breathable material is 20-80 mm. The winding ventilative material can prevent on the one hand that the molding sand from getting into ventilative through-hole and causing the jam, and on the other hand, ventilative material has formed the loose ventilative layer of one deck at the surface of main core, and this ventilative layer runs through in sand mold die cavity along main core, provides the passageway of the shorter line that conveniently collects for gaseous outer arranging, and when ventilative material's winding thickness was 20-80mm, ventilative material was difficult to the pressurized deformation in the pouring process, and the unblocked of gas circuit when effectively guaranteeing to exhaust.

Preferably, the breathable material is breathable rope. More preferably, the breathable rope is a straw rope or a plastic rope. Of course, a breathable cloth or other material may be used as the breathable material. The breathable rope is used, a gap is formed between the two ropes when the ropes are wound, so that the breathable passage can be used, certain hardness can be guaranteed by the ropes, and the ropes are not easy to deform after being wound.

Preferably, the ventilation through holes are round holes or oblong holes. The round hole or the long round hole is convenient to process, and the pipe strength of the round hole or the long round hole is higher.

It should be noted that the above description is provided to help understanding of the present invention, but does not limit the present invention. In addition, the above-described technical features of the present invention may be combined with each other as long as they do not conflict with each other. In addition, the above embodiments are only some embodiments, not all embodiments, and all other embodiments obtained by those skilled in the art without creative efforts belong to the protection scope of the present invention based on the embodiments of the present invention.

Claims

1. A sand mould cavity of a large casting is characterized in that a main core bar of the sand mould cavity is of a hollow tubular structure, and a pipe cavity of the main core bar is communicated with an exhaust hole on a face box of the sand mould cavity; the pipe wall of the main core rod is provided with a plurality of ventilation through holes, and the outer wall of the main core rod is wound with a ventilation material.

2. The sand mold cavity of a large casting according to claim 1, wherein the main core is a steel pipe, the diameter of the steel pipe is 80-300mm, and the wall thickness of the steel pipe is 4-20 mm.

3. A sand mold cavity for a large casting according to claim 1, wherein the air-permeable material has a winding thickness of 20 to 80 mm.

4. A sand mould cavity for a large casting according to any one of claims 1 to 3 wherein said air permeable material is air permeable rope.

5. The sand mold cavity of a large casting according to claim 4, wherein the air permeable rope is a straw rope or a plastic rope.

6. The sand mold cavity of a large casting according to claim 4, wherein the air-permeable through holes are round holes or oblong holes.