JPS61252336A - Heald for loom - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION (a) Field of Industrial Application The present invention relates to belts for looms, particularly belts suitable for air jet looms.

A conventional belt has a shape in which rod insertion holes for attaching to the belt frame are provided at both ends, and warp thread insertion holes are provided in the center. A large number of belts are attached in parallel to the belt frame, and by moving the entire belt frame up and down, vertical movement is imparted to the warp threads passing through the warp thread insertion holes of the belt to perform weaving.

Conventionally, wire belts made by processing wire were used, but recently water jet loom (W
Due to the limitations of ultra-high-speed looms such as JL) and air jet looms (AJL), and due to the increase in synthetic filament woven fabrics, the tensile force exerted on the wire belt has increased, and the warp density has increased, causing the belt itself to become thicker. There is a demand for thinner belts, and there is a rapid shift to flat belts.

When this flat belt is used for AJL, the following characteristics are mainly required.

(1) Good corrosion resistance.

(2) Good wear resistance.

(3) It has high strength and can be made to be as thin and lightweight as possible.

Regarding (1) corrosion resistance, the chemical components contained in the warp and weft threads corrode the belt, and regarding (2) abrasion resistance, as weaving machines become faster, the rate of wear with the threads becomes more important. Therefore, regarding weight reduction in (3), looms are becoming wider, and replacing the belt frame requires more labor than with wire belts, and there is a desire for even faster looms. It is a characteristic.

Conventionally, AJL type belts have mainly been made of 0.6 inch carbon steel plated with zinc, or galvanized and further plated with Cr (Unichrome method) (hereinafter referred to as conventional belts).

C) Problems to be Solved by the Invention Conventional belts have achieved the purpose of corrosion resistance by using the above-mentioned plating, but if the plating peels off from the uniformity of the metal, the 06-chi carbon steel itself has poor corrosion resistance.
It was easy to corrode. Furthermore, there are also problems such as increased cost due to plating and poor working environment for plating.

As for wear resistance, as mentioned above, plating is intended for corrosion resistance, so it cannot cope with the wear resistance that accompanies higher speeds. Furthermore, the strength, more specifically the hardness, of conventional belts is Hv 350, and it is difficult to reduce the thickness eQ to less than 25 m and the width f to less than 1.8 wi.
This is an obstacle to further increasing the speed of looms.

The present invention consists of 1. The purpose of the present invention is to provide a belt for a loom that has corrosion resistance, abrasion resistance, and strength enough to be lightweight without being galvanized like conventional belts.

2) Means for solving the problem As a result of various studies on the required characteristics of belts for looms, the inventors found that C0,5~i, os, Si
1. O'! J or less, Mn1.05J or less, Cr11~1
A belt made of martensitic stainless steel that has been subjected to low-temperature tempering and is composed of the remainder Fs and unavoidable impurities, or CuO, 5 to 5% is added to the above composition to improve corrosion resistance.
1.5'%, NiO, 3-1. O%, Mo0.
It has been found that a belt containing one or more of 3 to 2.0 Ls satisfies the required characteristics as an AJL type belt. In order to impart corrosion resistance, it is more desirable that the amount of carbide precipitated by low-temperature tempering be t-0.5% or less.

e) Effect First, the reason for limiting the components of the belt of the present invention will be described.

C is an essential element for imparting strength and wear resistance.
For this purpose, 0.5- or more is required.

However, if it is too large, the toughness and workability will deteriorate, so it is set at 1.0% or less.

si is added as a deoxidizing agent. However, if it becomes excessive, work hardening increases and cold workability decreases, so it is set to be less than i, os.

Mn is added as a deoxidizing agent, but if it exceeds 1.0 m, it impairs hot workability.

Cr combines with C to form carbide to improve wear resistance, and Cr dissolved in the matrix increases corrosion resistance.

From the balance with the C content, 11% or more is required. However, if it is too large, large eutectic carbides will increase, impairing workability, so it is set at 18% or less.

Cu + Ni + Mo is added to improve corrosion resistance. Cu is particularly effective against non-oxidizing acids such as HCl, and requires at least 0.5 copper. If the thickness exceeds 1.5 inches, hardness during heat treatment becomes difficult to obtain.

Ni also has the same effect as Cu, and is added in an amount of 0.3% to 1.0%.

Mo also has the same effect as Cur Ni, and the higher the content, the more effective it is, but it is expensive, so it is 0.3 to 2.0
%.

Even with stainless steel having the above composition, when an annealed material is used, the amount of Cr in the matrix decreases, and corrosion resistance cannot be expected and sufficient strength cannot be obtained.

Therefore, quenching and tempering impart strength, corrosion resistance, and abrasion resistance. The tempering process is particularly important, and when the tempering temperature is around 350°C, Cr carbides begin to precipitate in the matrix due to tempering of martensite, taking the form of needles in the matrix. Precipitates over the entire surface. When Cr precipitates over the entire surface of the matrix, corrosion resistance rapidly decreases due to a decrease in the amount of Cr in the matrix and an increase in strain energy due to carbide precipitation. Therefore, in the present invention, the precipitated carbides are suppressed as much as possible by low-temperature tempering. Figures 1 and 2 are microscopic microstructure photographs of the martensitic stainless steel t used in the belt of the present invention after low-temperature tempering at 300°C and high-temperature tempering at 500°C, respectively.
X20,000).

When tempering at a low temperature of about 300°C, almost no precipitated carbides are found, but as mentioned above, acicular carbides begin to precipitate around 350°C, and as shown in Figure 2, when tempering at a high temperature of 500°C, carbides are found all over the matrix. Precipitate. In the present invention, the presence of a certain amount of precipitated carbide is allowed within a range that does not significantly reduce corrosion resistance, but it is desirable to reduce the amount of precipitated carbide to 0.5 inch or less in terms of area ratio, while ensuring corrosion resistance. It imparts wear resistance.

In addition, in the belt of the present invention, it is desirable that the surface roughness be as low as possible in order to prevent yarn fuzzing and improve corrosion resistance.

f) Example The present invention will be explained below based on examples.

Martensitic stainless steel A-F with the chemical composition shown in Table 1 and conventional belt material C0, 69G carbon steel + Unichrome plating) Gt - After processing into a flat wire with a width of 2.4 cm and a thickness of 0.3 cm. , quenching, and low-temperature tempering to produce a belt as shown in FIG. 1. Also, for A, B, and F, 5
Tempering at a high temperature of 00°C was also performed separately.

Using the belts shown in Table 1 and above, a salt water spray rusting test using a 5 To NaCt aqueous solution was conducted twice each, and the corrosion resistance was evaluated based on the rust area ratio. The results are shown in Table 2, and the belt of the present invention (
Mul~8) is a conventional Unichrome plated product 9
Mo+, which is an element that imparts corrosion resistance, has corrosion resistance equivalent to
When a large amount of Ni r Cu f is contained, and when the amount of precipitated carbide is 0.5- or less in terms of area ratio, corrosion resistance is more effectively improved.

On the other hand, those that were tempered at a high temperature of 500°C (Oboro 10, 11.12) had a large amount of precipitated carbides and were significantly inferior in corrosion resistance.

From 1 to 9 washes, the tenobelt was used, and the abrasion resistance was evaluated by continuously passing yarn through the warp thread insertion holes of the belt using an abrasion testing apparatus as schematically shown in FIG. 2, and measuring the amount of weight loss. In addition,
The thread is nylon thread, and the thread running speed is 50? ? Z/mi
n, thread running distance 4000 m.

Measurements were performed twice under the condition of a tension of 10 g. The results are shown in Table 3, and it can be seen that the belt of the present invention (Al~8) has a lower weight loss t than the conventional belt and has excellent abrasion resistance.

Table 3 Table 3 also shows the hardness after quenching and tempering, and compared to the conventional belt's hardness of about 352 Hv,
The belt of the present invention has a Hv of 500 or more and has sufficient strength as a company machine belt, and the thickness and width can be less than conventional belts, making it possible to significantly reduce the weight.

g) Effects of the invention The present invention has excellent corrosion resistance due to plating, but compared to conventional belts in which it is difficult to expect wear resistance of both the plating layer and the base material, surface treatment such as plating is required. Of course, sufficient corrosion resistance can be expected without any
It has excellent abrasion resistance and strength, and is highly useful industrially as it can sufficiently handle high-speed looms.

[Brief explanation of the drawing]

Figure 1 is an electron microscope metallographic photograph of the martensitic stainless steel used in the belt of the present invention tempered at 250°C, and Figure 2 is a photograph of the martensitic stainless steel used in the belt of the present invention tempered at 500°C. An electron microscope metallographic photograph, FIG. 3 is a diagram showing a flat belt used in an example, and FIG. 4 is a schematic diagram of an abrasion test apparatus used for evaluating wear resistance. 1: Belt, 2: Warp insertion hole, 3: Rod insertion hole. Agent Patent Attorney Takaishi Tachibana Uma-, Rin 11 (to) ¥,,21i (',

Claims (1)

[Claims] 1. C0.5 to 1.0% by weight, Si1, O% or less,
A belt for a loom, comprising 1.0% or less of Mn, 11 to 18% of Cr, balance of Fe, and unavoidable impurities, and is made of martensitic stainless steel that has been tempered at a low temperature. 2. C0.5-1.0%, Si 1.0% or less in weight%,
Mn 1.0% or less, Cr 11-18% and Cu 0.5
~1.5%, Ni0.3~1.0%, Mo0.3~2.
1. A belt for a loom, characterized in that it is made of martensitic stainless steel which is made of one or more of the following: 0, the balance being Fe, and unavoidable impurities, and which has been tempered at a low temperature. 3. The loom according to claim 1 or 2, wherein the area ratio of precipitated carbides in the belt for a loom according to claim 1 or 2 is 0.5% or less. belt.