AU2016253565A1

AU2016253565A1 - A method for repairing a central trough of a scraper conveyor

Info

Publication number: AU2016253565A1
Application number: AU2016253565A
Authority: AU
Inventors: Erjing Dong; Dong Li; Jie Li; Qianqian Lu; Yan Ren; Yan Yang; Liang YUAN
Original assignee: Shandong Energy Heavy Equipment Group Hengtu Technology Co Ltd; Shandong Energy Heavy Equipment Manufacturing Group Co Ltd
Current assignee: Shandong Energy Heavy Equipment Group Hengtu Technology Co Ltd; Shandong Energy Heavy Equipment Manufacturing Group Co Ltd
Priority date: 2015-12-11
Filing date: 2016-11-02
Publication date: 2017-06-29
Anticipated expiration: 2036-11-02
Also published as: CN105458611B; CN105458611A; AU2016253565B2

Abstract

This present disclosure provides a method for repairing a central trough of a scraper conveyor, which includes: 1. measure a worn part of a central trough of a scraper conveyor; 2. choose a wear-resisting steel plate on the basis of a wear pattern of the central trough of the scraper conveyor; 3. fill up a groove of a worn surface under a chain of the central trough of the scraper conveyor, wherein the filled-up groove is not higher than the upper surface of the middle plate of the central trough of the scraper conveyor; fit the wear-resisting steel plate on the filled-up groove and perform fillet welding around them, wherein the wear-resisting steel plates have slotted holes which are used to perform welding; weld a wear-resisting steel plate on a joint between a ledge and a middle plate of the central trough of the scraper conveyor to make them into one piece; 4. remove a base plate of the central trough of the scraper conveyor; 5. choose a U-shaped plate of the up chain track and a U-shaped plate of the down chain track according to the measured wear loss of a worn surface of an up ledge and a worn surface of a down ledge of the central trough of the scraper conveyor, inset them into the ledge correspondingly, and perform fillet welding to their peripheries; wherein the U-shaped plate of the up chain track and the U-shaped plate of the down chain track have slotted holes in which welding is performed; 6. weld a new base plate to the base-plate position of the central trough of the scraper conveyor correspondingly; 7. machine a transition chamfer on the wear-resisting steel plate which is on a joint between the two ends of the central trough of the scraper conveyor, and accomplish the repairing. This present disclosure breaks the traditional repairing limit that the worn extent is less than 30%, and reduces the wasting of the worn-out central trough of the scraper conveyor, decrease the equipment cost of the coal mine, which is not only suited for repairing the small scraper conveyor but also the heavy or extra-heavy scraper conveyor. Fig. 3 r--| -2 Fig. 4

Description

Ό Ο (Ν > Ο (Ν Ο Ό m (Ν Ό Ο (Ν

A METHOD FOR REPAIRING A CENTRAL TROUGH OF A SCRAPER CONVEYOR TECHNICAL FIELD

The present disclosure mainly relates to the technical field of a central trough of 5 a scraper conveyor, and more particularly to a repairing method of a central trough of a scraper conveyor.

BACKGROUND

The central trough is a mass piece of the scraper conveyor, and occupies about 10 70-80% of the total weight or the total length of the scraper conveyor. The central trough is the carrying mechanism of the supplies and the body of the scraper conveyor, and the central trough is the critical piece which is configured in the middle of the scraper conveyor, thus the performance of the central trough directly influences the reliability and service life. The failure of the central trough is mainly caused by its 15 excessive wear which mainly includes the wear and tear of the middle plate and the base plate and secondly includes the wear and tear of the ledge.

At present, the repair standard for the able-to-be-repaired middle plate is that its wear extent does not to exceed 30% which is generally recognized by most of domestic machinery manufactures, and if the wear extent exceeds 30%, then the 20 middle plate is worthless. Under this standard, a mass of steel materials are wasted, and the cost of the coal mine is increased. Currently, the technology of laser cladding is the mainly technology for repairing the central trough of the scraper conveyor, and the most advanced cladding technology is laser cladding, but the price of the laser cladding technology is higher and the cladding thickness is only 1.5-2mm. Thus the 25 laser cladding technology can be used to repair the central trough of the small scraper conveyor, but cannot be used to repair the central trough of the heavy or extra-heavy scraper conveyors.

If the original design thickness of the middle plate of the central trough of the small scraper conveyor is 20mm, the rest thickness is 14mm with the wear extent of 30 30%. After conduct cladding on the middle plate, the partial thickness of the repaired middle plate is 16mm calculated at the cladding thickness of 2mm, which is less than ο (Ν > Ο (Ν Ο Ό m IT) (Ν Ό Ο (Ν the original design thickness of the middle plate by 4mm, but the wear-resisting property of the cladding layer is higher than the middle plate’s, so the repaired central trough of the scraper conveyor may meet the needs with the repaired thickness of 16mm. However, this is not applicable for the extra-heavy scraper conveyor. If the 5 original design thickness of the middle plate of the central trough of an extra-heavy scraper conveyor is 45mm, the rest thickness is 31.5mm with the wear extent of 30%. Calculated at the cladding thickness of 2mm, the thickness of the repaired middle plate is 33.5mm, which is less than the original design thickness of the middle plate by 11.5mm, which is a quite difference from the original design. As the closer to the 10 central part the less wear-resisting property, and it is close to the central part when the wear extent reaches to 30%, the wear-resisting property is greatly reduced. When the middle plate is worn, the welding joint of the middle plate and ledge also is worn, as shown in Fig. 2. But still, the middle plate of the scraper conveyor is repaired by using cladding technology, and after the repaired middle plate of the scraper conveyor 15 comes into service, the fast wear of the repaired middle plate make the central trough of the scraper conveyor cannot reach to the prospective quantity of the passed-coal as the welding joint of the middle plate and ledge cracks or the cladding layer is worn out in most cases. When the repaired central trough of the scraper conveyor joins the new one, there is an 11.5mm-staggered joint in height in the middle plate, this 20 staggered joint influences the operation of the scraper blade and causes the block of the scraper blade, so that the scraper blade comes into crash when it run to this position which causes damaged and even produces sparkle, influences the down hole safety in the production.

25 SUMMARY

Aim at the current defects and deficiencies in repairing the central trough of the scraper conveyor, the present disclosure accordingly provides a method of repairing the central trough of the scraper conveyor, which is described as follows: A method for repairing a central trough of a scraper conveyor includes the 30 following steps: ο (Ν > Ο (Ν Ο m ΙΟ (Ν Ο (Ν 1. measure a worn part of a central trough of a scraper conveyor; 2. choose a wear-resisting steel plate on the basis of a wear pattern of the central trough of the scraper conveyor; 3. fill up a groove of a worn surface under a chain of the central trough of the 5 scraper conveyor, wherein the filled-up groove is not higher than the upper surface of the middle plate of the central trough of the scraper conveyor; fit the wear-resisting steel plate on the filled-up groove and perform fillet welding around them, wherein the wear-resisting steel plates have slotted holes which are used to perform welding; weld a wear-resisting steel plate on a joint between a ledge and a middle plate of the 10 central trough of the scraper conveyor to make them into one piece; 4. remove a base plate of the central trough of the scraper conveyor; 5. choose a U-shaped plate of the up chain track and a U-shaped plate of the down chain track according to the measured wear loss of a worn surface of an up ledge and a worn surface of a down ledge of the central trough of the scraper 15 conveyor, inset them into the ledge correspondingly, and perform fillet welding to their peripheries; wherein the U-shaped plate of the up chain track and the U-shaped plate of the down chain track have slotted holes in which welding is performed; 6. weld a new base plate to the base-plate position of the central trough of the scraper conveyor correspondingly; 20 7. machine a transition chamfer on the wear-resisting steel plate which is on a joint between the two ends of the central trough of the scraper conveyor, and accomplish the repairing.

Conduct a join and assemble test on the central trough of the scraper conveyor so as to make sure that the scraper blade can conduct smooth transition. 25 As an optional solution, the wear-resisting steel plate includes a wear-resisting steel plate I and a wear-resisting steel plate II, the wear-resisting steel plate I is configured on the filled-up groove, and the wear-resisting steel plate II is configured on the joint between the middle plate and the ledge. Ό Ο (Ν > Ο (Ν Ο Ό m (Ν Ό Ο (Ν

Further, both the wear-resisting steel plate I and the wear-resisting steel plate II have a segmented structure, which include two segments at least. The adjacent segments of the wear-resisting steel plate I have an interspace, and the adjacent segments of the wear-resisting steel plate II also have an interspace, 5 Further, the wear-resisting steel plate further includes a wear-resisting steel plate III, the wear-resisting steel plate III are configured between the wear-resisting steel plate I and the wear-resisting steel plate II, and the wear-resisting steel plate III has a segmented structure, which includes two segments at least.

Further, the segments of the wear-resisting steel plate I and the wear-resisting 10 steel plate II are intersected.

Further, the segments of the wear-resisting steel plate I, the wear-resisting steel plate II and the wear-resisting steel plate III are intersected.

Further, after repairing, the differences of the heights of the wear-resisting steel plate I, the wear-resisting steel plate II and the wear-resisting steel plate III are less 15 than or equal to 2mm. If the differences, by matching steel plates with different thicknesses, are still more than 2mm, it should process the position where the wear-resisting steel plate is welded.

As an optional solution, the wear-resisting steel plates at both ends of the central trough of the scraper conveyor have a transition chamfer with the width of 15~30mm 20 and the height of 3~8mm.

Further, the method for repairing the central trough of the scraper conveyor includes: performing pretreatment before measuring the worn part of the central trough of the scraper conveyor.

Further, the pretreatment includes steps of disassembling, cleaning and sand 25 blasting.

This present disclosure has these advantages as below: 1) the solution of this present disclosure is suited for repairing various kinds of the central trough of the scraper conveyor, and is suited for different worn extent of the Ό Ο (Ν > Ο (Ν Ο Ό m (Ν Ό Ο (Ν central trough of the scraper conveyor, which breaks the traditional repairing limit that the worn extent is less than 30%, and reduces the wasting of resources. 2) the solution of this present disclosure is convenient to operate with lower cost, which is not only suited for repairing the small scraper conveyor but also the heavy or 5 extra-heavy scraper conveyor, the wear-resisting performance of the welded wear-resisting plate is higher than the wear-resisting performance of the original base material, and the performance of the repaired central trough of the scraper conveyor can exceed the original’s. 3) welding a wear-resisting plate on the middle plate and the ledge, to make them 10 into one piece, not only can increase the thickness of the worn part, but also reinforce the welding joint whose performance exceeds the originai’s. 4) welding a wear-resisting plate above the chain, to make the chain run on the added wear-resisting plate from beginning to end, can enhance the wear-resisting performance of that position. 15 5) the wear-resisting plate adopts segment structure, and each segment can be made by the offcut, which can increase the utilization ratio of the plates, reduce the failure rate of the central trough of the scraper conveyor, and decrease the influence to the base material by segmented welding. Also, it can enhance the welding strength by forming fillet weld around each wear-resisting plate because of the segmenting. 20 6) the welded wear-resisting steel plate has slotted holes which can be filled up through plug welding or fillet welding during the welding operation, thus it can enhance the welding strength and increase the stability. 7) the segments of the wear-resisting steel plates are intersected, it can decrease the blocking of the scraper blade and prolong the service life of the equipment. 25 8) for the same central trough of the scraper conveyor, it can adopt the welding wear-resisting steel plate with different thickness, which can reduce the amount of machining a lot. Ό Ο (Ν > Ο 2; (Ν Ο ΙΤ) Ό m ΙΟ (Ν Ό Ο (Ν 10 15

BRIEF DESCRIPTION OF THE DRAWINGS

Fig. 1 is a schematic structural view of the original design of the central trough of the scraper conveyor of the present disclosure;

Fig. 2 is a schematic view of the central trough of the scraper conveyor of the present disclosure;

Fig. 3 is a left view of the repairing method for the central trough of the scraper conveyor of the present disclosure;

Fig. 4 is a top view of the repairing method for the central trough of the scraper conveyor of the present disclosure; and

Fig. 5 is a schematic view of the butt joint of the middle plates of the present disclosure.

Symbol description from drawing: 1: U-shaped plate of the up chain track; 2: wear-resisting steel plate II; 3: wear-resisting steel plate I; 4: wear-resisting steel plate III; 5: base plate; 6: U-shaped plate of the down chain track; 1 worn surface of the up ledge; 2’: worn surface under the chain; 3’: worn surface of the middle plate; 4’: worn surface of the down ledge; 5’: worn surface of the base plate; R: chamfer.

20 DETAILED DESCRIPTION

In order to make the skilled in this art understand the present disclosure better, the technical solution of the present disclosure will now be described more clearly and fully hereinafter together with embodiments of the present disclosure, which are not all of the embodiments of the present disclosure. According to the exemplary 25 embodiments of this disclosure, all other similar embodiments obtained by those skilled in this art without any creative work belong to the protection scope of the present disclosure.

Hereinafter, a method for repairing a central trough of a scraper conveyor of the present disclosure is illustrated with the detailed exemplary embodiments. ο (Ν > Ο (Ν Ο νο ΙΟ m ΙΟ (Ν Ο (Ν

Embodiment One:

Take a central trough with the width of 1000mm of a scraper conveyor as an example in this embodiment, as shown in Fig. 1, in the original design, the thickness of the middle plate is 45mm, the thickness of the base plate is 30mm, and the inner width 5 of the central trough of the scraper conveyor is 1000mm. A scraper chain configured in the central trough of the scraper conveyor is used to convey the supplies above the middle plate (i.e., the up chain track) to the transfer loader, and the scraper chain round the sprocket shaft set of the head of the scraper conveyor and wrap back to bottom (i.e., the down chain track) of the central trough of the scraper conveyor, so as 10 to form a close loop.

According to the operation principle of the scraper conveyor and measured data, the worn surfaces of the central trough of the scraper conveyor mainly include the middle plate, and the base plate, and the contacting part of the ledge and the scraper blade, as shown in Fig. 2: 15 The major worn parts of the central trough of the scraper conveyor include: for the worn surface of the up ledge T and the worn surface of the down ledge 4’, the contacting parts of the ledges and the end of the scraper blade; for the worn surface of the middle plate 3’, the contacting parts of the scraper blade and the middle plate; and for the worn surface of the base plate 5’, the contacting part of the ledge and the 20 scraper blade and the base plate. In the actual, the worn part of the middle plate caused by the chain is usually worse than other parts.

As illustrated in Fig. 1, the welding manner between the middle plate and the ledge is a double V-shaped groove welding. Take the abrasion loss of the middle plate and the base plate is 50% as an example, as shown in Fig. 2, when the abrasion 25 loss of the middle plate 50%, the V-shaped groove welding on the middle plate no longer exists. Thus, if conduct the laser cladding only on the middle plate, it is very easy to break the welding between the plate and the ledge because of the operation such as pushing forwards the conveyor or pulling during the using process in the pit, so as to invalid the central trough of the scraper conveyor and influence the yield. Ό Ο (Ν > Ο (Ν Ο Ό m (Ν Ό Ο (Ν 8

Here are steps of repairing to be illustrated now:

Perform disassembling, cleaning and sand blasting on the central trough of the scraper conveyor and so on, so as to make it meets the standard requirement.

Number the clean central trough of the scraper conveyor, identify the position of 5 the wear-resisting plate, and measure many worn parts on the middle plate and the ledge. Choose one or two measure points on the corresponding position of each wear-resisting plate by principle, and determine the abrasion loss of each part and record the measuring data which is corresponding to the number of the central trough of the scraper conveyor. 10 Refer to Fig. 4, first fill up a groove of the worn surface under the chain 2’, the filled-up groove should be not higher than the upper surface of the middle plate, but may just lower than the upper surface of the middle plate by 1~2mm. Lay a wear-resisting steel plate I 3 on the groove and perform the fillet welding around them. All the wear-resisting steel plates have slotted holes which form plug welding holes or 15 fillet welding holes so as to enhance the welding strength. The chain keeps running on the wear-resisting steel plate I 3 and does not fall into the interspace between the steel plates from beginning to end, which is guaranteed by the width of the wear-resisting steel plate I 3, no matter of the central trough of the scraper conveyor is curved in horizontal or vertical. Use the same way on a wear-resisting steel plate II 2 20 welded on the weld joint of the middle plate and the ledge. The wear-resisting steel plate II 2 is used to make the middle plate and the ledge into one piece so as to enhance the weld strength of the middle plate and the ledge, after welding the wear-resisting steel plate II 2, the weld strength of the middle plate and the ledge is greater than the weld strength of the original design, and its performance exceeds the 25 performance of the original design. A wear-resisting steel plate III 4 is selectively weld which is determined by the width of the central trough of the scraper conveyor, there is no need to weld the wear-resisting steel plate III 4 when the width of the central trough of the scraper conveyor is lesser, because it can meet the operating requirements by welding the wear-resisting steel plate I 3 and the wear-resisting steel 30 plate II 2; while the width of the central trough of the scraper conveyor is large, there Ό Ο (Ν > Ο 2; (Ν Ο Ό m (Ν Ό Ο (Ν is quite a interspace after welding the wear-resisting steel plate I 3 and the wear-resisting steel plate II 2, it may need to weld multi rows of wear-resisting steel plates 1114.

The wear-resisting steel plate I 3, the wear-resisting steel plate II 2 and the 5 wear-resisting steel plates III 4 are segmented, each segment is determined by the specification of the central trough of the scraper conveyor and the practical situation. Adopting the segment structure has these advantages as following: (1) Increase the utilization ratio of the plates and avoid wasting the offcut, because each segment which is quite short can be made by the offcut. 10 (2) It will not influence the whole section of the central trough of the scraper conveyor even if the one of the segments is lost during the using process. But if the wear-resisting steel plate I 3, the wear-resisting steel plate II 2 and wear-resisting steel plates III 4 are one whole wear-resisting steel plate, once the welding of any end of the plate is cracked, it will influence the operation performance of the central trough of the 15 scraper conveyor because the continuing wear and tear will cause the whole plate fall off.

The segments of the wear-resisting steel plate I and the wear-resisting steel plate II are intersected. The segments of the wear-resisting steel plate I, the wear-resisting steel plate II and the wear-resisting steel plates III are intersected. 20 Adopting this configuration has these advantages as follows: during the operation, the scraper blade can pass the interspace of the segments one after another, rather than pass them at the same time, so as to guarantee the scraper blade can smoothly run on the wear-resisting steel plate, thus prolong its service life. If the interspace of the segments is in line, the scraper blade would drop into the interspace 25 and then the scraper blade would continue to run, repeatedly like this to operate in a wave pattern, the scraper blade would be scratched and blocked, which is adverse to the chain, for example, impacting the chain.

According to the worn loss of the worn surface of the up ledge 1 ’and the worn surface of the down ledge 4’ shown in Fig. 2, choose a wear-resisting plate with the ο (Ν > Ο (Ν Ο ΙΟ ΙΟ m ΙΟ (Ν Ο (Ν 10 proper thickness which is less than the thickness of the wear-resisting steel plate I 3, the wear-resisting steel plate II 2 or the wear-resisting steel plates III 4. The ledge is correspondingly inset with a U-shaped plate of the up chain track 1 and a U-shaped plate of the down chain track 6 which are bended on the basis of the shape of the 5 ledge, with using the fillet weld to weld their peripheries, and the U-shaped plates have slotted holes which are welded through the plug welding or fillet welding. Similarly, the U-shaped plate of the up chain track 1 and the U-shaped plate of the down chain track 6 are segmented optionally, besides the two above-mentioned advantages, it is also convenient to bend them into shape because of the length of the segment is 10 lesser.

After finishing the weld-forming, in order to reduce the situation of blocking the scraper blade, machine a transition chamfer R at the joint of the two ends of the central trough of the scraper conveyor, as shown in Fig. 5 illustrating the butt-joint of the plates, both ends have a transition chamfer with the width of 15~30mm and the 15 height of 3~8mm.

As the interspace of the base plate 5 and the middle plate is lesser, it is inconvenient to repair the base plate 5 and it costs a lot, thus the base plate 5 is replaced by a new one, similar with the former repairing. It should be noted that: it could perform the shaping, positioning and welding on the U-shaped plate of the down 20 chain track 6 after removing the base plate 5 by gas cutting.

Additionally, it should be understood that even though this specification is described as exemplary embodiments, each embodiment include not only one method solution, which is considered to make this specification clear. The specification should be deem as a whole by those ordinary skilled in this art, the method solution of 25 every embodiment can be can be properly devised to form other embodiments understood by those skilled in this art.

Claims

CLAIMS What is claimed is:

1. A method for repairing a central trough of a scraper conveyor, comprising: measuring a worn part of a central trough of a scraper conveyor; choosing a wear-resisting steel plate on the basis of a wear pattern of the central trough of the scraper conveyor; filling up a groove of a worn surface under a chain of the central trough of the scraper conveyor, wherein the filled-up groove is not higher than the upper surface of the middle plate of the central trough of the scraper conveyor; fitting the wear-resisting steel plate on the filled-up groove and performing fillet welding around them, wherein the wear-resisting steel plates have slotted holes which are used to perform welding; welding a wear-resisting steel plate on a joint between a ledge and a middle plate of the central trough of the scraper conveyor to make them into one piece; removing a base plate of the central trough of the scraper conveyor; choosing a U-shaped plate of the up chain track and a U-shaped plate of the down chain track according to the measured wear loss of a worn surface of an up ledge and a worn surface of a down ledge of the central trough of the scraper conveyor, insetting them into the ledge correspondingly, and performing fillet welding to their peripheries; wherein the U-shaped plate of the up chain track and the U-shaped plate of the down chain track have slotted holes in which welding is performed; welding a new base plate to the base-plate position of the central trough of the scraper conveyor correspondingly; machining a transition chamfer on the wear-resisting steel plate which is on a joint between the two ends of the central trough of the scraper conveyor, and accomplishing the repairing.
2. The method for repairing the central trough of the scraper conveyor according to Claim 1, wherein: the wear-resisting steel plate includes a wear-resisting steel plate I and a wear-resisting steel plate II, the wear-resisting steel plate I is configured on the filled-up groove, and the wear-resisting steel plate II is configured on the joint between the middle plate and the ledge.
3. The method for repairing the central trough of the scraper conveyor according to Claim 2, wherein: both the wear-resisting steel plate I and the wear-resisting steel plate II have a segmented structure, which include two segments at least.
4. The method for repairing the central trough of the scraper conveyor according to Claim 2, wherein: the wear-resisting steel plate further includes a wear-resisting steel plate III, the wear-resisting steel plate III are configured between the wear-resisting steel plate I and the wear-resisting steel plate II, and the wear-resisting steel plate III has a segmented structure, which includes two segments at least.
5. The method for repairing the central trough of the scraper conveyor according to Claim 3, wherein: the segments of the wear-resisting steel plate I and the wear-resisting steel plate II are intersected.
6. The method for repairing the central trough of the scraper conveyor according to Claim 3, 4 or 5, wherein: the segments of the wear-resisting steel plate I, the wear-resisting steel plate II and the wear-resisting steel plate III are intersected.
7. The method for repairing the central trough of the scraper conveyor according to Claim 4 or 5, wherein: after repairing, the differences of the heights of the wear-resisting steel plate I, the wear-resisting steel plate II and the wear-resisting steel plate III are less than or equal to 2mm.
8. The method for repairing the central trough of the scraper conveyor according to any one of Claims 1 to 5, wherein: the wear-resisting steel plates at both ends of the central trough of the scraper conveyor have a transition chamfer with the width of 15~30mm and the height of 3~8mm.
9. The method for repairing the central trough of the scraper conveyor according to Claim 1, further comprising: performing pretreatment before measuring the worn part of the central trough of the scraper conveyor.
10. The method for repairing the central trough of the scraper conveyor according to Claim 1, wherein: the pretreatment includes steps of disassembling, cleaning and sand blasting.