CN103553325A - Method and device for stretching optical fiber preform rod - Google Patents

Abstract

The invention relates to a method and a device for stretching an optical fiber preform rod. The device comprises an RIC rod which is formed by combining a quartz sleeve and a quartz core rod, wherein an upper handle of the RIC rod is clamped and fixed by an upper clamp; a lower handle is clamped and fixed by a lower clamp; the upper clamp, the lower clamp and a heating furnace can be moved up and down; in a stretching process, heat is generated by moving the heating the furnace from top to bottom, the upper clamp moves upwards and the lower clamp moves downwards to provide stretching force. The heating furnace is moved from top to bottom at a speed of V1; and meanwhile, the upper clamp moves upwards at the speed of V2, and the lower clamp moves at the speed of V3 for stretching the softened RIC rod, so that the optical fiber preform rod is produced.

Description

A kind of method that preform is stretched and device

Technical field

The present invention relates to preform processing technique field, especially relate to a kind of method that preform is stretched and device.

Background technology

In order to improve the production efficiency of fibre-optical drawing, as the preform of producing fibre parent material progressively to large size future development.A kind of high-level efficiency, the production method of large-scale optical fiber prefabricating stick cheaply in patent document CN101328012A, have been introduced: the rock quartz core rod that VAD method is produced and quartz socket tube are combined to form RIC rod (as Fig. 1), utilize process furnace from bottom to up RIC rod to be heated to (as Fig. 2), use vacuum pumping technology to make, together with the molten contracting of plug and quartz socket tube, to form preform simultaneously.

The length of the quartz socket tube using in patent document CN101328012A (1 length L in Fig. 1) is longer, and the efficiency of producing preform is also just higher, and the material use efficiency of quartz socket tube is also just higher simultaneously.

While adopting the mode that above-mentioned process furnace heats from bottom to top, according to physical principle, quartzy under molten state, the maximum height that normal atmosphere can hold up rock quartz core rod is about 4.6m, when if quartz socket tube length (L in Fig. 1) surpasses 4.6m, in drawing process, rock quartz core rod will, with respect to quartz socket tube down sliding (position as shown in Fig. 2 8), affect the quality of preform.

That is to say, in the method described in patent document CN101328012A, cannot use the quartz socket tube long over 4.6m.

Summary of the invention

The invention provides a kind of new drawing process, can solve the technical problem of plug landing in above-mentioned drawing process, can realize the use of long quartz socket tube, produce the quartzy prefabricated rods of overlength, improve the production efficiency of quartzy prefabricated rods.

The invention provides a kind of device that preform is stretched, this device comprises: the RIC rod being combined by quartz socket tube and rock quartz core rod, and the upper handle of this RIC rod is gripped by upper fixture, and lower handle is gripped by lower clamp; Wherein, upper fixture, lower clamp, process furnace can move up and down; In drawing process, by process furnace is mobile, produce heat from top to bottom, upper fixture moves up, lower clamp moves down provides drawing force.

Further, process furnace moves from top to bottom with speed V1, and meanwhile, upper fixture upwards moves with speed V2, and lower clamp moves with speed V3 downwards, and softening RIC rod is stretched, and produces preform.

The present invention also provides a kind of method that preform is stretched, and it comprises the following steps:

Step (1) is combined into RIC rod by quartz socket tube and rock quartz core rod;

Step (2) is used the upper handle that fixture fixes this RIC rod, with lower clamp, fixes lower handle;

Step (3) is in drawing process, and process furnace is mobile from top to bottom produces heat, and upper fixture moves up, lower clamp moves down provides drawing force.

Further, process furnace moves from top to bottom with speed V1, and meanwhile, upper fixture upwards moves with speed V2, and lower clamp moves with speed V3 downwards, and softening RIC rod is stretched, and produces preform.

The present invention overcome that prior art exists because of the oversize defect that cannot stretch of quartz socket tube, can realize the use of long quartz socket tube, realize the production of overlength optical fiber prefabricated rods, improve the production efficiency of preform.

Accompanying drawing explanation

Fig. 1 is the structure iron of the qualified RIC rod produced: 1 is quartz socket tube, and 2 is rock quartz core rod, and 3 is upper handle, and 4 is lower handle, and L represents the length of quartz socket tube.

Fig. 2 is the schematic diagram of existing stretching device during for long quartz socket tube; Wherein 1 is RIC rod; 2 is the preform having stretched; 3 is the upper handle of RIC rod; 4 is the lower handle of RIC rod; 5 is the upper fixture for stretching; 6 is the lower clamp for stretching; 7 is process furnace; 8 is rock quartz core rod landing position.

Fig. 3 is the schematic diagram according to stretching device of the present invention, and wherein 1 is RIC rod; 2 is the preform having stretched; 3 is the upper handle of RIC rod; 4 is the lower handle of RIC rod; 5 is the upper fixture for stretching; 6 is the lower clamp for stretching; 7 is process furnace.

Embodiment

Below in conjunction with Figure of description, the present invention is specifically described.

First, by quartz socket tube and rock quartz core rod combination RIC rod, as shown in fig. 1, RIC rod comprises quartz socket tube 1, rock quartz core rod 2, and the upper handle 3 of welding and lower handle 4.

RIC rod is placed on stretcher, and upper handle 3 is gripped by upper fixture 5, and lower handle 4 is gripped by lower clamp 6.Wherein, upper fixture 4, lower clamp 6, process furnace 7 can move up and down.

In drawing process, by process furnace 7, produce heat, upper fixture 5, lower clamp 6 provide drawing force.

7 pairs of RIC rods 1 of process furnace heat, and RIC rod 1 is softening, and with speed, V1 moves from top to bottom.

Meanwhile, upper fixture 5 upwards moves with speed V2, and lower clamp 6 moves with speed V3 downwards, and softening RIC rod is stretched, and produces preform.

Because process furnace heats RIC rod from top to bottom, rock quartz core rod is to soften successively from top to bottom, the not softening rock quartz core rod in bottom can provide to softening rock quartz core rod enough anchorage forces, therefore do not have the situation of rock quartz core rod and quartz socket tube relatively sliding, the theoretical length of quartz socket tube is will being no longer subject to the restriction of drawing process.

Drawing process in the present invention is: utilize process furnace to heat from top to bottom, rock quartz core rod and quartz socket tube are softening successively from top to bottom, while softening below, rock quartz core rod can provide enough anchorage forces, and the relatively sliding of quartz socket tube and rock quartz core rod can not occur.

According to this method, the information of the quartz socket tube of having produced and the rear preform that stretches is as shown in table 1 below at present, can significantly improve the production efficiency of preform.

Table 1

Quartz socket tube length/m	Optical fiber prefabricating rod outside diameter/mm	Overall length/m after stretching	Estimate drawing optical fiber length/Km
				6	150	11	16000
6	180	7.8	16000

The above, it is only exemplary embodiments of the present invention, not technical scope of the present invention is imposed any restrictions, any trickle modification, equivalent variations and modification that every foundation technical spirit of the present invention is made above enforcement, all still belong within the scope of technical scheme of the present invention.

Claims (4)

1. device preform being stretched, is characterized in that this device comprises:

The RIC rod being combined by quartz socket tube and rock quartz core rod, the upper handle of this RIC rod is gripped by upper fixture, and lower handle is gripped by lower clamp; Wherein, upper fixture, lower clamp, process furnace can move up and down; In drawing process, by process furnace is mobile, produce heat from top to bottom, upper fixture moves up, lower clamp moves down provides drawing force.

2. device according to claim 1, is characterized in that:

Process furnace moves from top to bottom with speed V1, and meanwhile, upper fixture upwards moves with speed V2, and lower clamp moves with speed V3 downwards, and softening RIC rod is stretched, and produces preform.

3. method preform being stretched, is characterized in that comprising the following steps:

Step (1) is combined into RIC rod by quartz socket tube and rock quartz core rod;

Step (2) is used the upper handle that fixture fixes this RIC rod, with lower clamp, fixes lower handle;

Step (3) is in drawing process, and process furnace is mobile from top to bottom produces heat, and upper fixture moves up, lower clamp moves down provides drawing force.

4. method according to claim 3, is characterized in that:

Process furnace moves from top to bottom with speed V1, and meanwhile, upper fixture upwards moves with speed V2, and lower clamp moves with speed V3 downwards, and softening RIC rod is stretched, and produces preform.

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