JPS5935816A - Built-up type roll - Google Patents

Abstract

PURPOSE:To join tightly a hard ring to a roll shaft, by utilizing the difference between the amounts of shrinkage basing on the difference between the coefficients of thermal expansion to fix the hard roll ring loaded with a side pressure to the shaft. CONSTITUTION:The coefficient of thermal expansion of a hard roll ring 2 is made smaller than that of a roll shaft 1. The ring 2 is inserted to a roll body 1a of the shaft 1 having an annular flange 1b. And the ring 2 is fixed to the shaft 1 by locking them with the aid of a locking flange constituted of a screwed part 1c of the shaft 1 and a nut ring 5 in a warm or hot atmosphere. Thus, in this built-up roll, the ring 2 is tightly joined to the shaft 1 without using an adhesive material and causing an unnecessary stress.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an assembly type roll using a hard ring made of a super high alloy or a ring made of a cemented carbide.

Conventionally, this type of rolling roll has a structure in which only the part that contacts the rolled material is a hard ring, and the hard ring is joined to the roll shaft by a required means. The following methods are used to join and attach the hard ring.

(1) Shrink fit the hard ring onto the roll shaft or kl,
A method of fixing a wedge-shaped ring by press-fitting it between a hard ring and a 1-1-R shaft.

(2) A method of applying adhesive between the hard ring and the roll shaft to fix it.

(3) A method in which lateral pressure is applied in the axial direction of the hard ring using a blower or hydraulic unit, and the tightening is fixed between flanges installed at both ends of the roll shaft. (Side pressure tightening is a law.) In the above method, in method (1), shrink fit stress due to shrink fit or stress that attempts to split the hard ring in the radial direction by a wedge acts. If this stress is superimposed with the stress generated during rolling, there is a drawback that the hard ring is likely to break. In method (2), the adhesive deteriorates due to heat or fatigue, and there is a risk that the adhesive portion will peel off during use, making it impossible to withstand rolling operations. Method (3) is
If the side pressure is appropriate, it is effective in alleviating the bending or thrust stress that occurs in the hard ring during rolling, and is reasonable as a roll assembly method. However, when using kitsu,
It is necessary to form a threaded hole in the roll shaft for the bolt to push the wedge into, and the strength of the roll shaft is reduced due to the notch created by this female threaded hole. The reaction force of the lateral pressure applied to the sleeve acts on the roll shaft, and tensile stress is always working on the roll shaft. Considering the fact that the strength of the roll shaft is reduced as described above4, it is sufficient to firmly support the hard ring. It is not possible to apply large side pressure, which poses a problem in practical use.

On the other hand, in the case of method (3) using hydraulic Uniso 1~, if the roll itself is large, it will cost 40Qton~50Qton.
This requires a hydraulic unit that generates 0 tons of force, and requires a highly rigid mounting jig to transmit the hydraulic pressure to the hydraulic unit 1, and the jig must be prepared according to the size and shape of the roll. However, the equipment cost was high and it was uneconomical.

The present invention aims to solve the above-mentioned problems, and by effectively utilizing the difference in coefficient of thermal expansion (the amount of shrinkage), lateral pressure is applied to the hard roll ring to make the hard roll ring. It is an object of the present invention to provide an assembly type roll configured to be easily fixed to a roll shaft.

The present invention will now be described based on the embodiments shown in FIGS. 1 and 2 below.

In FIG. 1, (11 is a roll shaft formed of, for example, commonly used cast steel, etc.), and an annular flange (1b) is integrally formed at the negative end of the roll body (1a), and The side end part has a male screw (IC).(2) is inserted into the roll cylinder (1a) and one end part has a flange part (1a).
The hard roll ring (3) that comes into contact with b) is a separate ring that is similarly fitted onto the roll cylinder (1a), and the Sebaret I ring (3) has a coefficient of thermal expansion that is close to the roll axis ( ]) In this example, for example, 36N+-Fe alloy is used.Furthermore, (4
) is a nut ring forming a tightening flange that is screwed onto the male screw (IC) of the roll shaft (1), and its material is, for example, the same as that of the roll shaft (1).

With the above configuration, the hard roll ring (2) is attached to the roll shaft (1) via the separate ring (3), and the nut ring (4) is tightened by force, and the nut ring (4) and the flange part (1b) It is clamped and fixed between the abutting parts of.

Next, the roll assembly procedure will be described. First, the hard roll ring (2) and the separate ring (
3) to the roll cylinder (1a), and hard mouth 5
nA4- Bring the nut ring (2) into contact with the end face of the flange portion (1b), and screw the nut ring (4) onto the male screw (1c).

Next, the nuts were brought into an annealing furnace or a heating furnace, and heated to a predetermined temperature (500°C or less in this example), which will be described later.
is rotated quickly and the separate ring (3) and hard roll ring (21 are tightened toward the flange part (1b). Cooled down to room temperature under this tightened state. That is, in the tightened state at high temperature, the roll shaft ( 1) Flange part (1b)
and the length between the nut ring (4) and the ring +21. +3
The total length of 1 is the same, but as mentioned above, the roll axis (11) has a larger coefficient of thermal expansion, so the separate ring (3) tightened by the nand ring (4) during cooling and the hard roll The amount of shrinkage of the ring (2) is small, and the amount of shrinkage between the flange portion (1b) of the roll shaft (1) and the nand ring (4) is large, so the separate ring (3)
) and the hard roll ring (2) are subjected to a substantial compressive force in the axial direction by the flange portion (1b) and the nand ring (4). That is, based on the difference in the amount of contraction between the roll shaft (11 and the separate ring (3) due to their different linear expansion coefficients, the separate ring (3) and the hard roll ring (2) are connected to the roll shaft ( The larger contraction (in the axial direction) of 1) allows the tightening f1 to be fixed.

In addition, in Fig. 1, if the hard roll ring (2) is made of cemented carbide, the coefficient of thermal expansion is extremely small with respect to the roll axis 1), so the hard roll ring (2) itself is made of a separate ring (3). ), and in this case, the Severe ring (3) can be made of ordinary steel.

In FIG. 2, the roll axis (1') has a shape that is smaller than the average thermal expansion coefficient of the hard roll ring (2') and the protective ring (described later) that are attached in this embodiment.
For example, it is made of 75h 221J 3 Cr alloy. +51 in the figure. +6) are protective rings placed on both sides of the hard roll ring (2'), and Nano 1
- The ring (4') is made of the same material as the roll shaft (1'). It is optional whether both protective rings f5+, (6) are attached or only the - side is attached, and this depends on the size of the hard roll ring (2').

In the example shown in Fig. 2, the process of removing the hard roll ring (2') from the roll shaft (1') is similar to that described above, and in cooling after heating, the hard roll ring (2') is attached to the roll shaft (1'). The amount of shrinkage (in the axial direction) of the hard roll ring (2') is larger than the total shrinkage of the hard roll ring (2') and both protective rings (5) and (61), so the hard roll ring (2') is
51, (6), the flange portion (1b') and the Nano 1 ring (4') are tightened and stably supported.

In addition, the hard roll ring (2) is removed from the vehicle in the case of Fig. 1 in the following manner. First, loosen the Nano 1-ring (4) while soaking it to a temperature slightly higher than the processing temperature during assembly. Alternatively, use a lathe to cut a portion of either the roll link (2) or the separate ring (3) into half.
The nut ring (4) can be easily removed by cutting in the same direction and releasing the lateral pressure to zero. In the one shown in Fig. 2, there is a hard roll ring (2') or a double guard ring (5').
), (6) as described above and remove the nano) ring (4').

The relationship between the heating temperature (T) during assembly and the necessary side pressure (F) determined from the rolling conditions and roll shape is approximately calculated by the following formula, and the heating temperature may be selected based on this.

) Here, E5: Coefficient of elasticity of the roll shaft α5: 0 - Coefficient of thermal expansion of the roll shaft S5: Cross-sectional area of the part of the roll shaft where the roll ring is fitted Ep: Coefficient of elasticity of the roll ring αR: Coefficient of thermal expansion SR: Cross-sectional area 7! R= Axial length 8-EM; Elastic modulus αM of separate ring and protective ring; Same thermal expansion coefficient SM 2 Same cross-sectional area ρM: Separate I-ring axial length Jffi or total axial direction j of the protective ring be.

- By optimizing the heating temperature according to the above formula, the side pressure necessary for assembly and operation can be obtained.

As described above, according to the present invention, by effectively utilizing the magnitude of the coefficient of thermal expansion, the hard roll ring can be reliably attached to the roll shaft using conventional equipment.

[Brief explanation of the drawing]

FIGS. 1 and 2 are sectional views showing two embodiments of an assembly type roll according to the present invention. flL (1') Roll shaft (1a) Roll cylinder (Ib), (lb') Flange part (IC) Male screw +2+, (2') Hard roll ring (:A) Valley 1-ring (4) Nut ring ( 51, (6) 'Damage Ring Patent Applicant Population Tatekinzoku Co., Ltd. 11- Figure 1

Claims (1)

[Claims] 1. An annular flange is formed on each roll cylinder of the roll shaft, and an annular hard part is formed on the same roll cylinder. 71'l-ru ring is fitted, and the same hard roll ring is tightened between the above flange parts using the tightening type 1 flange provided on the other side of the I-ru cylinder. An assembly type in which the thermal expansion coefficient of the hard roll ring is made smaller than that of the roll shaft in the in-standing second roll, and a 1-type flange is tightened in the warm or hot state. 1-
Le. 2. The assembly type roll according to claim 1, wherein the tightening type flange is constructed by a male screw formed on the roll shaft and screwing/sotring with the male screw. 3. Fit at least one separate ring into the roll cylinder along with the above hard roll ring! The thermal expansion coefficient of at least one of the hard roll ring and Sepathy 1 to ring is l-! - The assembly type roll described in item 1 of the scope of the patent, characterized in that the roll axis is smaller than that of the roll shaft. 4. Patent i1i'? characterized in that the 1V uniform thermal expansion coefficient of the hard roll ring and the separator 1/1 l ring is smaller than the thermal expansion coefficient of the roll shaft. The assembly type roll described in Item 3 of Item 1.11 of the Request.