CN202241907U

CN202241907U - Composite machine head for annular coating of small-bore three-layer PE (polyethylene) anticorrosion tube

Info

Publication number: CN202241907U
Application number: CN2011201799954U
Authority: CN
Inventors: 李生军; 贾宏庆; 何小林
Original assignee: Tianhua Institute of Chemical Machinery and Automation Co Ltd
Current assignee: Tianhua Institute of Chemical Machinery and Automation Co Ltd
Priority date: 2011-05-28
Filing date: 2011-05-28
Publication date: 2012-05-30
Anticipated expiration: 2021-05-28

Abstract

The utility model relates to a composite machine head for annular coating of a small-bore three-layer PE (polyethylene) anticorrosion tube, which is structurally characterized in that an inner layer core mold is compounded with an inner layer mold body in an embedding manner and is connected with an outer layer core mold to form a first material hole tubular flow channel. An inner layer adjusting ring is arranged between the inner layer mold body and the outer layer core mold. The outer layer core mold is compounded with an outer layer mold body in an embedding manner and is connected with an outer layer outer mold to form a second material hole tubular flow channel. An outer layer adjusting ring is arranged between the outer layer mold body and the outer layer outer mold. A shrinkage angle A of the first and second tubular flow channels is 60-90 degrees. The bottom of the inner layer core mold is provided with a heating rod jack. The scheme of the composite machine head is employed in the three-layer PE anticorrosion production of the small-bore steel tube, so that the manufacturing and running costs are reduced, the production line can be conveniently adjusted, the scratching between inner holes of the machine head and the steel tube is reduced, and the product rejection rate is low. By means of a test, the product has few interlayer bubbles and high bonding strength, and the quality of the product completely complies with the requirements of SY/T0413-2002 standards.

Description

Small-bore three layers of PE anti-corrosion pipe annular coats uses composite machine head

Technical field

The utility model belongs to the coating of a kind of three layers of PE anti-corrosion pipe annular and uses composite machine head.

Background technology

In the natural gas long-distance transport pipes are carried, adopt three layers of PE anti-corrosion pipe in a large number.The anticorrosive coat of three layers of PE structural anticorrosion pipe is made up of FBE, primer adhesive layer and polyethylene (PE) layer; This anticorrosion structure has overcome the limitation of homogenous material; Combine the advantage of FBE and polyethylene layer, interlayer combines closely, makes the combination property of whole protective system reach best; The premium properties of this anticorrosion structure obtains the attention on anticorrosion boundary, various countries, has also obtained developing rapidly and extensive use in China.In the natural gas long-distance transport pipes were carried, Trunk Line often adopted three layers of PE anti-corrosion pipe of big medium caliber, take-off line gradually transition be in small-bore anti-corrosion pipe.Three layers of PE anti-corrosion pipe of big medium caliber are all adopted the side direction winding shaping process both at home and abroad, steel pipe is done the helical form rotation and is advanced on production line, and primer and PE layer are band shape and are wound on the steel pipe afterwards by the rubber roller compacting, to improve adhesive strength.Small-caliber steel pipe is because caliber is little, and strength and stiffness are little, and rotation transmits very unstablely on production line, when the rubber roller compacting, is easy to generate flexural deformation, and to make three layers of PE anticorrosion so the side direction winding shaping process is not suitable for small-caliber steel pipe.At present, domestic many producers adopt two cover individual layer heads to dispose vacuum negative pressure device respectively that small-caliber steel pipe is carried out three layers of PE is anticorrosion.When annular coated, steel pipe was kept straight on and is not rotated, and accomplishes Overmolded through the case that dusts, primer head, PE head and spray cooling device successively.Primer head and PE head are the mono-layer tube joint, extrude primer pipe and PE pipe respectively and are coated on the outer surface of steel tube that scribbles epoxy powder, and the independent vacuum negative pressure device of each head configuration adopts the mode that vacuumizes negative pressure to discharge the interlayer bubble and realize the interlayer compacting.

Prior art adopts two cover heads, two cover vacuum negative pressure devices; Between primer head and PE vacuum negative pressure device, must reserve the operating space, package unit occupy-place on drive line is very long, and after dusting to spray cooling before anticorrosive coat be in soft state backing roll can not be set; Make backing roll very big like this in the span at this place; Oscillating quantity is very big during the steel pipe operation, is easy to scratch with the endoporus of head or vacuum negative pressure device, causes product rejection (referring to Fig. 1).Secondly, roll, often make interlayer leave over a small amount of bubble, influence the interlayer adhesive strength because annular coating can not add milling roller as the side winding.

Summary of the invention

In view of the deficiency of prior art, the purpose of the utility model aims to provide the coating of a kind of three layers of PE anti-corrosion pipe annular and uses composite machine head.

The purpose of the utility model is to realize through following technical scheme:

A kind of small-bore three layers of PE anti-corrosion pipe annular coats uses composite machine head, is to be made up of heating rod jack, internal layer core, internal layer mould body, internal layer adjustable ring, outer core, outer mould body, outer adjustable ring and outer external mold.Internal layer core and internal layer mould body embedding mutually are compound and combine with outer core, form the first material mouth tubulose runner; Be equipped with the internal layer adjustable ring between internal layer mould body and outer core, embedding is compound mutually with outer mould body for outer core, and combines with outer external mold, forms the second material mouth tubulose runner; Outer mould body is equipped with outer adjustable ring with outer outer intermode, and the first tubulose runner and the second tubulose runner angle of throat A are 60 °～90 °; There is the heating rod jack internal layer core inside.

The utility model compared with prior art, the advantage that has:

In the coating of three layers of PE anti-corrosion pipe annular is produced, adopt composite machine head to replace two unit heads to have following characteristics:

(1) vacuum negative pressure device is reduced to a cover by two covers.

(2) the head bracing or strutting arrangement is reduced to a cover by two covers.

(3) heating temperature-control system is reduced to a cover by two covers.

(4) the two-layer compound head have two independently charging aperture and two overlap independently tubulose molding runners, interior outer flow passage arranged concentric, the external mold of the core double as inner flow passage of outer flow passage.The composite machine head overall dimension is more bigger than a unit head; But owing to reduced by a head; One cover vacuum negative pressure device, and saved the operating space between two unit heads, make the occupy-place length of composite machine head on drive line be reduced to 40% of unit head significantly.

When (5) the unit head coats, between PE layer and the primer layer, all be outside compound between primer layer and the FBE,, also possibly leave a small amount of bubble, influence adhesive strength though applied negative pressure of vacuum.When adopting composite machine head, be compound between PE layer and the primer layer, completely cut off air fully, can not have the interlayer bubble in head inside.After PE layer and primer layer were compound, composite bed thickness increased, and can apply bigger negative pressure, helps discharging the bubble between composite bed and the FBE, and adhesive strength is improved.

(6) manufacturing cost of composite machine head and operating cost are far below two unit heads.

(7), invisible at the whole primer of extruding in the coating process because PE and primer are compound in composite machine head inside.In case the primer discharging is unusual, can only find when Pipe Cutting that this makes finds that fault lags behind, and causes waste product to increase.So, when each Pipe Cutting, must be through color judgment primer discharging situation.

Description of drawings

Fig. 1 annular coats three layers of anticorrosion shaping schematic view of PE of steel pipe.

Fig. 2 the utility model structural representation.

The specific embodiment

As shown in Figure 2.A kind of small-bore three layers of PE anti-corrosion pipe annular coats uses composite machine head, is to be made up of heating rod jack 1, internal layer core 2, internal layer mould body 3, internal layer adjustable ring 4, outer core 5, outer mould body 6, outer adjustable ring 7 and outer external mold 8.Internal layer core 2 and internal layer mould body 3 embedding mutually are compound and combine with outer core 5, form the first material mouth tubulose runner; 5 of internal layer mould body 3 and outer cores are equipped with internal layer adjustable ring 4, and embedding is compound mutually with outer mould body 6 for outer core 5, and combines with outer external mold 8, form the second material mouth tubulose runner; Outer mould body 6 and 8 of outer external molds are equipped with outer adjustable ring 7, the first tubulose runners and the second tubulose runner angle of throat A is 60 °～90 °; There is heating rod jack 1 internal layer core 2 inside.

The core of outer core 5 is two-layer shared by internal layer core 2, internal layer mould body 3, outer mould body 6 and outer external mold 8; The external mold that serves as internal layer; Inside and outside two-layer charging aperture axially be staggeredly arranged along head, ectonexine is provided with the thickness evenness that the separate regulating ring is regulated each layer respectively.PE and primer get into composite machine head by separately charging aperture respectively; Head internal layer runner is a primer layer; Distribute each self-forming tubulose through the runner in the composite machine head; Inside and outside two-layer pipe arranged concentric, inner flow passage flat segments outlet gets into composite log and outer flow passage converges, what extrude from composite log is the composite bed of PE and primer.

Composite machine head configuration one cover vacuum negative pressure device, the adjusting that the vacuum in the vacuum chamber can be level and smooth to adapt to the composite bed moulding, is convenient to discharge the bubble between composite bed and the FBE, improves adhesive strength.

Composite machine head adopts inside and outside mode of heating simultaneously, and periphery adopts the heating of resistance heated circle, and heating rod jack 1 is arranged at internal layer core 2 bottoms, inserts the bar type internal heater in the hole.The installation site of heating rod will be paid special attention to; Because the axis direction of heating rod is identical in the discharging direction of flat segments with primer; If when too far away, the temperature of water passage surface can present strip and distribute, and influences evenness of discharge property each other for too close runner of heating rod and heating rod.For guaranteeing primer evenness of discharge property, the heating rod jack is not deep into the flat segments part of primer, and is relatively more reasonable when structural configuration so yet.

Claims

1. small-bore three layers of PE anti-corrosion pipe annular coats and uses composite machine head; Be to constitute by heating rod jack (1), internal layer core (2), internal layer mould body (3), internal layer adjustable ring (4), outer core (5), outer mould body (6), outer adjustable ring (7) and outer external mold (8); Embedding is compound and combine with outer core (5) mutually to it is characterized in that internal layer core (2) and internal layer mould body (3), forms the first material mouth tubulose runner; Be equipped with internal layer adjustable ring (4) between internal layer mould body (3) and outer core (5), embedding is compound mutually with outer mould body (6) for outer core (5), and combines with outer external mold (8), forms the second material mouth tubulose runner; Be equipped with outer adjustable ring (7) between outer mould body (6) and outer external mold (8), the first tubulose runner and the second tubulose runner angle of throat A are 60 °～90 °; There is heating rod jack (1) internal layer core (2) inside.