Centrifugal integral cast metal mould for dual-tray flange straight pipes

Abstract

A centrifugal integral cast metal mould for dual-tray flange straight pipes comprises a left tapered plug tray, a through-wall flange pipe borne mould, fastening bolts, a non-through-wall flange pipe mould, a wedge, a fitting pin, a resin sand withdrawal core, a transition section pipe mould and a right tapered plug tray; the resin sand withdrawal core is connectively mounted between the through-wall flange pipe borne mould and the non-through-wall flange pipe mould through the fastening bolts, the through-wall flange pipe borne mould and the transition section pipe mould are connected through the fastening bolts, the transition section pipe mould and the non-through-wall flange pipe are connected through the fastening bolts, and the resin sand withdrawal core is connectively mounted between the non-through-wall flange pipe mould and the right tapered plug tray through the fastening bolts. By the arrangement, the mould is combined and assembled in design, requirements of different through-wall flanges on position are met, mass production can be realized through horizontal centrifugal casting, market requirement is met, environment protection is facilitated, dust can be fully recycled, environment friendly casting is truly realized, and the centrifugal integral cast metal mould is applied to the technical field of centrifugal casting.

Description

technical field [0001] The invention relates to a centrifugal integral casting metal mold of a double-disk flange straight tube in the technical field of metal mold manufacturing, in particular to a centrifugal integral casting of a double-disc flange straight tube. Background technique [0002] At present, a large number of double disc flanges are used in pressure pipelines to connect with valves, fire hydrants, expansion joints, etc., and are widely used in metallurgy, mining, subway, chemical industry, sewage treatment and other industries. At present, most of the pressure-bearing water pipelines in the domestic and foreign markets use centrifugal ductile iron pipes. However, due to the difficulty of demoulding, the centrifugal integral casting of the double-flange centrifugal ductile iron pipe cannot be realized. Traditional centrifugal casting can only produce straight pipes with disk or socket, because the cast pipe formed by centrifugal casting needs to be pulled out...

AI Technical Summary

Problems solved by technology

The main problems of welding double-disk flange pipes: (1) The material of the weld seam is inconsistent with that of the cast pipe body, and the strength of the "heterogeneous" weld seam is low

(2) Stress concentration in the welding area cannot be completely eliminated

(3) The flanges at both ends of the pipe are manually assembled before welding, and the size error is large; it is difficult to ensure the concentricity of the two flange holes and the parallelism of the disk surface due to the influence of thermal stress during the welding process

(4) At present, there is no evaluation standard for cast iron welds at home and abroad, so users cannot evaluate the welding quality

Among them, the main problems of ordinary sand casting are uneven wall thickness and bending deformation; the main problems of lost foam casting are slag inclusion, many pores, and high water leakage rate in hydraulic test.

In particular, it should be pointed out that the smaller the pipe diameter and the longer the length, the greater the probability of the above-mentioned defects. It is difficult to form a flange pipe with a length of less than DN200 and a length of more than 2 meters. Even if it is formed, the pass rate is very low. , unable to meet market demand

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