CN100361804C

CN100361804C - Technology and apparatus for forming worm channel with plastic liner of centrifugal pump

Info

Publication number: CN100361804C
Application number: CNB011341815A
Authority: CN
Inventors: 蒋龙福; 蒋兆平; 陈小生
Original assignee: ZHANGZE CHEMICAL EQUIPMENT FAC
Current assignee: Yixing Zhous Pump Industry Co Ltd
Priority date: 2001-11-15
Filing date: 2001-11-15
Publication date: 2008-01-16
Anticipated expiration: 2021-11-15
Also published as: CN1363455A; CN100513030C; CN101077539A

Abstract

The present invention relates to an improvement on a plastic-lined centrifugal pump, particularly to a method and a device for processing the plastic-lined flow channel of the centrifugal pump. In order to obtain a plastic-lined layer with the ideal volute flow channel of corrosion resistance and wear resistance, the metal volute casing of the centrifugal pump is first lined with the plastic-lined layer with a certain thickness by mould pressing, and then the plastic-lined layer is cut, milled and processed according to the track of a design template so as to obtain the needed flow channel. The method and the processing device of the present invention have the advantages of plastic lining simplicity, high work efficiency and production cost reduction, and the plastic-lined centrifugal pump with the ideal flow channel can also be obtained to enable the plastic-lined flow channel to obtain great flexibility and overcome the contradiction between anticorrosion wear resistant material, and plastic lining and processing. The method of the present invention has the advantages of high molecular weight and fine performance of a lining, poor plastic flowability and incomparable superiority.

Description

Plastic-lining centrifugal pump volute runner forming method

Technical field

The invention relates to improvement, relate in particular to the road moulding of centrifugal pump lining creeping plastic-lining centrifugal pump.

Background technology

People are the conveying that solves corrosivity and contain granule medium, a kind of cost-effective be to adopt the steel lining plastic centrifugal pump, the plastic layer that promptly has certain thickness anticorrosive wear-resistant, for example ultra-high molecular weight polyethylene at the compound one deck of centrifugal pump metal pump housing flow passage position lining.Yet because it is not high usually to have the plastic flow property of anticorrosive anti-wear character, usually can only adopt the mold pressing lining method, and present these class plastics of lining, for the favourable demoulding and obtain having higher-density and certain thickness backing layer, employing is made external mold with the centrifugal pump metal pump housing, with the circular or sub-circular structure of plastic lining runner mold pressing lining, as described in Chinese patent 94242592.Yet track is circular runner, can cause centrifugal pump efficient and hydraulic characteristic(s) to descend, and this decline is especially more obvious in the performance of low discharge high pressure centrifugal pump.For overcoming the defective that the mold pressing lining can not obtain desirable volute track runner, Chinese patent 86100758 discloses a kind of employing somatotype piece mould mold pressing lining method and mould, it is to be made external mold by the lining metal spiral case, adopt press the design of volute runner and by some capable of being combined, decompose snail lobe piece and the plug assembling die makes to serve as a contrast mould, by heating unidirectionally extruded moulding, thereby between interior outer mold, obtain having the lining plastic layer of volute runner.This lining method, the one, production efficiency is lower; The 2nd, because pump housing spiral case runner complexity adopts unidirectionally extruded backing layer density low, easily cause shrinkage cavity, make the anticorrosion antiwear performance descend, and be difficult to obtain having the monolithic lining layer of even compact that especially at the relatively large pump of lining, this defective is more obvious.For overcoming above-mentioned deficiency, Chinese patent 96117172 has been done improvement to it, discloses molded lining method of the two-way extrusion die of a kind of employing and mould, but only has been that part has overcome low, the uneven defective of backing layer density, and production efficiency is not improved.Above-mentioned in addition direct lining obtains having the method and the mould of volute runner, and not only production efficiency is low, cost is high; And the mounting or dismounting die process is cumbersome, and required locked mode pressure is big, and mould especially pump case external mold damages easily.Direct mold pressing lining volute runner besides, can only the lining molecular weight little, the ultra-high molecular weight polyethylene that melt index is high, but this can reduce the wearability of backing layer again, obtain mold pressing lining not only corrosion resistant but also wear-resisting ultra-high molecular weight polyethylene, then difficulty comparatively.

Summary of the invention

The objective of the invention is to overcome the deficiency of above-mentioned prior art, a kind of directly the lining melt viscosity is big, molecular weight is higher not only corrosion resistant but also wear-resistant plastic are provided, simultaneously can obtain more satisfactory runner lining again, and method is easy, the plastic-lining centrifugal pump volute runner forming method that work efficiency is high.

The object of the invention realizes, its method is to be external mold with the centrifugal pump metal spiral case earlier, by conventional mold pressing lining method at the compound plastic layer in spiral case overcurrent position, obtain the sub-circular plastic lining layer, and then on plastic lining layer, process the required runner volute runner of involute (as be) by the mechanical machining of finalizing the design, so both overcome the deficiency that common mold pressing lining can only obtain the low and hydraulic characteristic(s) difference of the efficiency of pump that circular flow channel brings; Having overcome simultaneously direct lining again, to obtain the work efficiency that the volute runner brought low, especially is not suitable for the deficiency that lining has the higher molecular weight plastics.Specifically, plastic-lining centrifugal pump volute runner forming method of the present invention, comprise with the metal spiral case pump housing and make external mold, at first obtain sub-circular runner plastic lining layer by the mold pressing lining, it is characterized in that serving as a contrast molded after, the template of milling that will have required design flow road track is fixed on the pump housing one side, obtains required design runner along this runner orbiting motion in plastic lining layer processing by milling cutter.The required runner of plastic lining layer of the present invention, owing to be to determine by milling mould design flow road track, therefore, fully can be by design ideal or required runner are processed milling on the mould, again by on plastic lining layer, obtaining required runner along this track cutting milling method, change and to mill mould runner track and can obtain the plastic-lining centrifugal pump of different required runners, thereby changed the deficiency that plastic-lining centrifugal pump is more difficult to get desirable required runner, make the plastic-lining centrifugal pump runner form and have bigger flexibility.The present invention mills template and is not particularly limited with being connected of pump, can be contained in the front pump cover side, also can be contained in the rear pump cover side, looks easy to process and definite.

The device of the present invention's processing flow channel on plastic lining layer, comprise runner calibrator and cutting tool, it is characterized in that said runner calibrator is the template of milling of digging the design runner, said cutting tool is and mills the milling cutter that slide unit is arranged on the mould runner sidewall contact site handle of a knife.Slide unit on the milling handle, main effect is to mill machining accuracy and prolong the milling cutter shank life-span for guaranteeing, slide unit can be as ball or roller bearing, axial sleeve of bushing friction pair, so both guaranteed that milling cutter moved along milling mould design flow road track, and reduced the rotation of milling cutter high speed again and milled the wearing and tearing that the friction of mould runner track causes handle of a knife and runner track.Be the fineness of raising processing flow channel, the said milling cutter of the present invention, its blade section preferably adopts circular configuration or circular distribution structure.The milling cutter width preferably equates substantially with required runner, can cutting at one time finish like this; For the runner broad, then can by up and down twice or repeatedly cutting finish.

Plastic-lining centrifugal pump volute runner forming method of the present invention owing to be to pass through behind the first mold pressing lining to get by template track machining on backing layer, not only makes the lining flow get simply again, has improved lining greatly and has moulded efficient and yield rate, has saved production cost; And can the lining performance better but mobile difference have more plastics of HMW.Because the plastic lining layer runner is to determine by milling template runner track, therefore can obtain comparatively ideal designs runner such as volute runner and some special runners, make lining creeping road obtain to have bigger flexibility, and improved the efficient and the hydraulic characteristic(s) of plastic-lining centrifugal pump greatly, can raise the efficiency 15% than mold pressing lining circular flow channel centrifugal pump.

Description of drawings

Fig. 1 has circular flow channel plastic lining layer centrifugal pump schematic diagram for common mold pressing lining.

Fig. 2 mills the mould vertical view for embodiment.

Fig. 3 mills mould side-looking structural representation for embodiment.

Fig. 4 is an embodiment milling cutter structural representation.

Fig. 5 is a kind of facing cutter structural representation of embodiment.

Fig. 6 is the another kind of facing cutter structural representation of embodiment.

Fig. 7 is an embodiment plastic lining layer volute runner machining schematic diagram.

The specific embodiment

Embodiment: referring to accompanying drawing, be external mold, obtain having certain thickness circle or sub-circular runner ultra-high molecular weight polyethylene or polypropylene plastic lining layer 2 (Fig. 1) by the mould pressing method lining to be involute centrifugal pump metal spiral case 1.To cooperate the template 4 (Fig. 2) of milling to be fixed on the metal pump housing 1 front pump cover side (Fig. 7) then with front pump cover by fixing threaded hole 5 with volute runner 3.For helping accurate location, mill the template inboard and be provided with positioning convex ring 6 (Fig. 3).Be with bearing 7 (Fig. 4) with the handle of a knife 8 corresponding location, mould runner track place of milling of the wide milling cutter 9 of runner.During machining, the Bearing support on the milling cutter shank is attached to and mills mould runner track inboard, moves and carries out milling and cut along milling mould runner track, goes out volute runner (Fig. 7) in the plastic lining layer Surface Machining of sub-circular runner.Milling cutter 9 can be at the evenly fixing some blades 11 (Fig. 5) of circular beater plate 10 side faces, also can be that the periphery at circular beater plate directly is processed with dentation blade 12 (Fig. 6).

Change and mill template runner track, can on the lining plastic layer, process the runner of different tracks.

Milling head of the present invention partly can also have other structures, and the milling cutter width can also be little than runner, and the both sides design has radian about milling cutter, so that runner is processed required curved surface in both sides up and down.

Claims

1. plastic-lining centrifugal pump volute runner forming method, comprise with the metal spiral case pump housing and make external mold, at first obtain sub-circular runner plastic lining layer by the mold pressing lining, it is characterized in that serving as a contrast molded after, the template of milling that will have required design flow road track is fixed on the pump housing one side, obtains required design runner along this runner orbiting motion in plastic lining layer processing by milling cutter.

2. according to the described plastic-lining centrifugal pump volute of claim 1 runner forming method, it is characterized in that said metal spiral case pump housing runner line style and mill template runner track roughly the same.

3. according to the described plastic-lining centrifugal pump volute of claim 1 runner forming method, it is characterized in that the plastics that serve as a contrast are ultra-high molecular weight polyethylene or polypropylene.