CN1143548A

CN1143548A - Method for manufacturing cylinder tooth bit of cast steel and ductile iron

Info

Publication number: CN1143548A
Application number: CN 95115507
Authority: CN
Inventors: 孙海林; 孙进平
Original assignee: Individual
Current assignee: Individual
Priority date: 1995-08-19
Filing date: 1995-08-19
Publication date: 1997-02-26
Anticipated expiration: 2015-08-19
Also published as: CN1058649C

Abstract

A method for manufacturing columnar-tooth drill bit with cast steel or nodular cast iron, which is used for mining, features use of casting technology. The profile of drill bit is formed by precision casting using metal mould. Its primary air path is directly cast by sand core with supported location. Said sand core has a iron tube with many small holes as core reinforcement. A cup-type sand shell surrounds the iron tube having a locating sleeve at its lower end. An easily cut locating plate has two internal arc runners, two side air ventholes and sand core locating hole two side ventholes connected with those of riser head. Its advantages include low machined amount and high mechanical properties, quality and precision of drill bit.

Description

The manufacture method of cast steel, cylindrical toothed drill of nodular graphite cast iron

The present invention relates to the manufacture method of cast steel, cylindrical toothed drill of nodular graphite cast iron.

Columnar drill is big in the mine use amount, and consumption is also big.It is reported to consume about 60,000 in national year by only major diameter columnar drill, each average price reaches over thousands of unit, will consume every year about 6,000 ten thousand yuan, and is costly.

The technology of producing the ductile iron drill bit now is: system punching block and sandbox-moulding-cast-sand removal-saw rising head-heat treatment-brill main ventilation hole-other machining-edge alloy column.There is solid cast waste molten iron in this manufacture method, and foundry goods exists shrinkage cavity, sand holes, machining boring to waste a series of shortcomings such as man-hour.Now relevant for the report that improves method for making cylindrical toothed drill of nodular graphite cast iron, but do not see report so far about the cast steel method for making cylindrical toothed drill.By resin sand core the main ventilation hole is directly cast out, this is a much progress, but has the sand removal difficulty; Main ventilation hole exhaust system is blocked, and easily produces core; Running gate system is side cast, and MOLTEN STEEL FLOW is rapid, and sand mold is caused excess impact, causes sand washing, produces a series of shortcomings such as sand holes.

The objective of the invention is to overcome the shortcoming that above-mentioned manufacture method exists, propose a kind of new method of making cast steel, cylindrical toothed drill of nodular graphite cast iron.

The present invention realizes like this.Its main points are that the workpiece profile adopts metal mold.The main ventilation hole has the core that supports the location directly to cast out by one.Core is done arbor by the iron pipe that has many apertures, and tube wall outside is a glass molding sand shell, iron pipe have the positioning sleeve that supports by muscle bottom, the positioning sleeve center is placed with support iron.Support ferropexy in nowel bottom centre hole.Easily cut spacer and have two arc ingates, two side steam vents and core locating hole.Two side steam vents communicate with the side steam vent of rising head sandbox.Two arc ingates communicate with the pouring basin of rising head sandbox.The upper end of iron pipe arbor is ganged up mutually with the sand cover.

Compared with prior art, the present invention has following advantage: (1) bit contour adopts metal mold, has improved the mechanical property of foundry goods, and wherein impact toughness improves 30%-40%, has improved the dimensional accuracy and the fineness of foundry goods, and the foundry goods precision can reach the CT8-9 level.(2) adopt the iron pipe that has a lot of apertures to do arbor, rigidity, the moulding that has improved core is easy, exhaust is smooth and easy, sand removal is convenient, eliminated core.(3) the arc ingate that adopts bilateral symmetry to arrange, cavity filling process is steady, and the foundry goods heat distribution is reasonable, helps the discharge of gas, has improved product quality, makes yield rate improve 20%.(4) the main ventilation hole directly casts out by 2 cores that support the location are arranged, and has simplified process for machining, has reduced cost, surplus each drill bit on average reduces by 40 yuan.

Below in conjunction with accompanying drawing invention is described in further detail.

Fig. 1 is formative technology figure of the present invention.

Fig. 2 easily cuts spacer A-A sectional drawing.

Fig. 3 easily cuts the spacer vertical view.

Fig. 4 is the core sectional drawing.

Fig. 5 is a rising head sandbox vertical view.

1, metal mold, 2, support iron, 3, core, 4, iron pipe arbor, 5, the central row pore, 6, aperture, 7, easily cut spacer, 8, the rising head sandbox, 9, the sand cover, 10, pouring basin, 11, the arc ingate, 12, the side steam vent, 13, core locating hole, 14, the side steam vent, 15, positioning sleeve, 16, cup molding sand shell, 17, mo(u)ld bottom half bottom centre hole.

Embodiment

The manufacture method of cast steel, cylindrical toothed drill of nodular graphite cast iron, technological process is: metal mold is carried out preheating, coat, preheating before the cast; When carrying out said process, make core; Following core mould assembly, cast, sand removal, heat treatment, other machining, edge alloy column.

The present invention is in the moulding operation, and the workpiece profile adopts metal mold 1.The main ventilation hole directly casts out by the core 3 that supports the location is arranged.Core 3 is done arbor 4 by the iron pipe that has a lot of apertures 6, and tube wall outside is a glass molding sand shell 16, iron pipe have the positioning sleeve 15 that supports by muscle bottom, there is the iron 2 of support at positioning sleeve 15 centers.Easily cutting spacer 7 has and waters 11, two side steam vents 12 in two arcs and 13, two side steam vents 12 of core locating hole communicate with the side steam vent 14 of rising head sandbox 8.The upper end of iron pipe arbor 4 is ganged up mutually with sand cover 9, and the hole of iron pipe arbor 4 is a central row pore 5.In drill bit top machine boring, in the hole, join the edge alloy column.

Claims

The manufacture method of cast steel, cylindrical toothed drill of nodular graphite cast iron, technological process is: metal mold is carried out preheating, coat, preheating before the cast; When carrying out said process, make core; Following core mould assembly, cast, sand removal, heat treatment, other machining, edge alloy column; The invention is characterized in the moulding operation that the workpiece profile adopts metal mold; The main ventilation hole directly casts out by the core 3 that supports the location is arranged, and sand mold 3 is done arbor 4 by the iron pipe that has a lot of apertures, and the tube wall outside is a glass molding sand shell, iron pipe have the positioning sleeve 15 that supports by muscle bottom, positioning sleeve 15 centers have one to support iron; Easily cutting spacer 7 has two arc ingates 11, two side steam vents 12 and 13, two side steam vents 12 of core locating hole and communicates with the side steam vent 14 of rising head sandbox 8; The upper end of iron pipe arbor 4 is ganged up mutually with sand cover 9.