CN103846610A - Core rod isometric restoration process - Google Patents

Abstract

The invention provides a core rod isometric restoration process, which comprises the following steps of 1) checking the quality of core rods and judging whether the core rods have restoration value; 2) making a restoration scheme for restorable core rods; 3) annealing the core rods at the temperature of between 680 and 720 DEG C generally, and keeping the temperature for 4 to 6 hours; 4) straightening the core rods, and controlling the curvature to be less than or equal to 4mm; 5) machining; 6) performing surfacing on surface cracks of the core rods by gas submerged arc welding generally, wherein the surfacing preheating temperature is 140-180 DEG C, a power supply is 170-180A, holding temperature after surfacing is 780-800 DEG C and is kept for 6 to 8 hours, and the hardness is HB330-380; 7) performing heat treatment; 8) machining; 9) plating the surfaces of the core rods with chrome or zinc, wherein the thickness is 0.04-0.07mm and the hardness is HRC62-65; 10) inspecting. By the core rod isometric restoration process, the cost is reduced, the production efficiency and the product quality are improved and the service life is prolonged.

Description

The isometrical renovation technique of plug

Technical field

The present invention relates to produce the plug of steel pipe, relate in particular to an isometrical renovation technique of plug of wearing steel pipe.

Background technology

Plug is one of major part participating in steel pipe rolling distortion, hot finished steel pipe is higher with plug piercing temperature, to bear very high axial tensile force and radial compressive stress and thermal wear simultaneously, therefore the performance to plug and surface quality are had relatively high expectations, the main manifestations that plug lost efficacy is heat fatigue, sticky erosion, corrode, distortion, cracking etc., thermal fatigue cracking is the most extreme damage type, cause in sum service life low, production efficiency is not high, product quality declines, for cost-saving, enhance productivity, must repair old plug.

Summary of the invention

The object of this invention is to provide one cost-saving, improve production efficiency and product quality, the isometrical renovation technique of plug increasing the service life.

The present invention is achieved in that the isometrical renovation technique of plug, it is characterized in that comprising the following steps:

1), check plug quality and determine whether the independent the other side of plug who there is the value of repairing: a, flexibility is greater than to 5 ㎜, wait aligning; B, mandrel surface crack depth is greater than to the processing of scrapping of 10 ㎜, be less than 10 ㎜ etc. to be repaired; C, the old plug screw rule that meet above-mentioned reparation requirement are checked, if can not tighten etc. to be repaired;

2), recoverable plug is formulated to recovery scenario:

A formulates annealing process according to diameter of rod size: temperature general control, at 680 °-720 °, is incubated 4-6 hour;

B aligns the bar of flexibility >=10 ㎜, controls in the ㎜ of flexibility≤4;

C, to mandrel surface crackle, commonly uses gas submerged arc bead welding, built-up welding preheat temperature: 140 °-180 °; Control power supply: 170-180A; Heap postwelding holding temperature: 780 °-800 °, continue 6-8 hour; Hardness: HB 330-380;

D processes the plug of heap postwelding, makes its surface smoothness 0.8, flexibility≤1 ㎜;

E chrome-faced, zinc-plated, thickness 0.04-0.07 ㎜, hardness: HRC:62-65;

3), by plug annealing, temperature general control is at 680 °-720 °, insulation 4-6 hour;

4), plug is aligned to control flexibility≤4 ㎜;

5), machined;

6), to mandrel surface crackle, conventional gas submerged arc bead welding, built-up welding preheat temperature: 140 °-180 °; Control power supply: 170-180A; Heap postwelding holding temperature: 780 °-800 °, continue 6-8 hour; Hardness: HB 330-380;

7), heat treatment;

8), machined;

9), chrome-faced or zinc-plated, thickness 0.04-0.07 ㎜, hardness: HRC:62-65;

10) inspection.

The present invention has saved cost, has improved production efficiency and product quality, has extended service life.

Detailed description of the invention

1), check that plug quality determining whether has to repair and be worth the isometrical renovation technique of plug, is characterized in that comprising the following steps:: a, flexibility is greater than to independent the other side of plug of 5 ㎜, waits for aligning; B, mandrel surface crack depth is greater than to the processing of scrapping of 10 ㎜, be less than 10 ㎜ etc. to be repaired; C, the old plug screw rule that meet above-mentioned reparation requirement are checked, if can not tighten etc. to be repaired; 2), recoverable plug is formulated to recovery scenario: a and formulate annealing process according to diameter of rod size: temperature general control, at 680 °-720 °, is incubated 4-6 hour; B aligns the bar of flexibility >=10 ㎜, controls in the ㎜ of flexibility≤4; C, to mandrel surface crackle, commonly uses gas submerged arc bead welding, built-up welding preheat temperature: 140 °-180 °; Control power supply: 170-180A; Heap postwelding holding temperature: 780 °-800 °, continue 6-8 hour; Hardness: HB 330-380; D processes the plug of heap postwelding, makes its surface smoothness 0.8, flexibility≤1 ㎜;

E chrome-faced, zinc-plated, thickness 0.04-0.07 ㎜, hardness: HRC:62-65; 3), by plug annealing, temperature general control is at 680 °-720 °, insulation 4-6 hour; 4), plug is aligned to control flexibility≤4 ㎜; 5), machined; 6), to mandrel surface crackle, conventional gas submerged arc bead welding, built-up welding preheat temperature: 140 °-180 °; Control power supply: 170-180A; Heap postwelding holding temperature: 780 °-800 °, continue 6-8 hour; Hardness: HB 330-380; 7), heat treatment; 8), machined; 9), chrome-faced or zinc-plated, thickness 0.04-0.07 ㎜, hardness: HRC:62-65; 10) inspection.

Claims (1)

1. the isometrical renovation technique of plug, is characterized in that comprising the following steps:

1), check plug quality and determine whether the independent the other side of plug who there is the value of repairing: a, flexibility is greater than to 5 ㎜, wait aligning; B, mandrel surface crack depth is greater than to the processing of scrapping of 10 ㎜, be less than 10 ㎜ etc. to be repaired; C, the old plug screw rule that meet above-mentioned reparation requirement are checked, if can not tighten etc. to be repaired;

2), recoverable plug is formulated to recovery scenario:

A formulates annealing process according to diameter of rod size: temperature general control, at 680 °-720 °, is incubated 4-6 hour;

B aligns the bar of flexibility >=10 ㎜, controls in the ㎜ of flexibility≤4;

C, to mandrel surface crackle, commonly uses gas submerged arc bead welding, built-up welding preheat temperature: 140 °-180 °; Control power supply: 170-180A; Heap postwelding holding temperature: 780 °-800 °, continue 6-8 hour; Hardness: HB 330-380;

D processes the plug of heap postwelding, makes its surface smoothness 0.8, flexibility≤1 ㎜;

E chrome-faced, zinc-plated, thickness 0.04-0.07 ㎜, hardness: HRC:62-65;

3), by plug annealing, temperature general control is at 680 °-720 °, insulation 4-6 hour;

4), plug is aligned to control flexibility≤4 ㎜;

5), machined;

6), to mandrel surface crackle, conventional gas submerged arc bead welding, built-up welding preheat temperature: 140 °-180 °; Control power supply: 170-180A; Heap postwelding holding temperature: 780 °-800 °, continue 6-8 hour; Hardness: HB 330-380;

7), heat treatment;

8), machined;

9), chrome-faced or zinc-plated, thickness 0.04-0.07 ㎜, hardness: HRC:62-65;

10) inspection.