朝日護謨工業所 List of Products and Services

Due to steam vulcanization molding, we can manufacture custom products ranging from palm-sized to Φ1500×4000L without the need for molds. (Some products may require simple jigs.) We can accommodate a wide range of rubber materials, from natural rubber to various synthetic rubbers, fluorine rubber, silicone rubber, etc., allowing us to propose rubber materials tailored to solve specific problems. Regarding delivery times, we have established a system for single-item orders, so the average delivery time for standard products is 7 to 10 days. Steam vulcanization molding offers high flexibility in size, making our delivery industries diverse, including food machinery, electronic machinery, textile machinery, marine equipment, film manufacturing equipment, special printing machinery, steel production lines, conveying equipment, and packaging machinery.

• Rubber
• Contract manufacturing
• Processing Contract

This is a rubber lining component made of fluororubber (Buna-N). It is a rubber-lined part used to grip components during their movement on the production line. Initially, it was processed using urethane rubber, but urethane rubber is weak against "heat (high temperatures)" and issues such as surface melting occurred, so "fluororubber (Buna-N)" that can withstand high-temperature use was chosen. By changing the rubber material, the problems caused by heat (high temperatures) were resolved, but to address surface slipping, a "knurling process" was applied to the rubber lining surface. The specifications for the knurling are "depth 1mm, pitch 2mm, groove angle 90°." This processing improved surface slipping, and the peaks of the knurling enhanced the holding power during clamping, leading to improvements in the speed of the production line and the alignment of component movement.

• Transport and handling robots
• Rubber

This is a ceramic rubber lining pulley for the coke transport line. Due to the coke (coal), even rubber with excellent wear resistance can deteriorate early, so we use a pulley that has a rubber plate with embedded ceramics that is vulcanized and bonded. The ceramics are in a ring shape, which ensures the reliable removal of coke attached to the belt, minimizes clogging, and prevents cracking due to interference between ceramics. Since the ceramics are baked onto the rubber plate, it also has moderate cushioning properties, effectively removing any irregularities from the attachments on the belt conveyor. Although it is more expensive compared to rubber pulleys, it offers benefits such as reduced replacement work and unnecessary line stops due to its durability for long-term use.

• Conveyor
• Ceramics
• Rubber

This is an ebonite roll with acid-resistant properties used in pickling tanks. The core material is SUS, but there are concerns about acid resistance with just SUS, so it is covered with "ebonite," which has excellent acid resistance except for the bearing parts. Generally, only the pipe body is rubber-lined, but this product is used in an acid pickling line, requiring measures against sulfuric acid splashes, so rubber lining has also been applied to the shaft and flange surfaces. The area through which the product passes is limited to the roll surface of the body, but it is necessary to add a drainage feature to prevent dilute sulfuric acid from leaking out. Two grooves have been cut into the shaft, and a rubber ring for drainage is set in these grooves to prevent unnecessary dilute sulfuric acid from flowing out.

• Rubber
• Plastic processing machines (cutting and rolling)
• Other processing machines

This is a rubber roller used in film equipment. Air entrapment may occur between the transported film and the rubber roll. There are various methods to remove or reduce air, and one of them is to process the roll surface with diamond-shaped grooves, as done in this product. The rubber material selected is NBR (white), and the diamond cut was processed with a 30mm pitch. It is necessary to pay attention to the feeding speed, rotation speed, and depth of the grinding stone during processing. Since this is a film transport roll, even the slightest alteration, such as foreign substances or air bubbles, is unacceptable; therefore, meticulous care must be taken in managing the manufacturing process, including material storage and other aspects outside of production.

• Processing Contract
• Rubber
• Other processing machines

This is a nip roll for sheet manufacturing equipment. It is made of two layers of silicone rubber, with the upper layer being white silicone rubber with a hardness of 70°. The dimensions are Φ250 (outer diameter of rubber) × Φ240 (outer diameter of the lower layer) × 1920L (length), and the surface has a "fine diamond cut processing." The specifications for the diamond cut processing are "groove width 0.5 mm × depth 0.5 mm × P2.5 mm × angle 18°," and it has been applied to the entire surface of the roll. Taper processing has been performed on both ends of the roll within a range of 200 mm to stabilize the tension of the sheets being produced. The lower layer is black silicone rubber with a hardness of 70°. The dimensions are Φ240 (outer diameter of rubber) × Φ200 (core diameter) × 1920L (length), and it is necessary to perform dimensional adjustments through outer diameter processing to create the two layers. The purpose of the diamond cut on the rubber roll surface is to eliminate air pockets in the nipped sheets, which seems to contribute to improving defects caused by air pockets in the production site. Additionally, by making the lower layer of rubber black, visibility has been increased, making it easier to determine the timing for replacement.

• Resin processing machine

This is a heat-resistant silicone rubber roller for hot stamping. It seems to be used for printing on the top surface of electronic pianos. The size is "Φ300×Φ267×300L," which is considered large for hot stamping, and the rubber thickness is over 20mm. The heater's set temperature is "220-230°C." Given the rubber thickness of over 20mm, heat retention is taken into account, and high heat resistance is required for the silicone rubber, so heat resistance enhancers have been added to meet the requirements. In general hot stamping, rubber sleeves (rubber tubes) that do not adhere rubber to the core are common, but depending on the size being transferred and the pressure applied, there are cases where a rubber roller with rubber adhered to the core, like the product listed, is chosen. Additionally, we can also manufacture "hot stamping rubber rollers" with groove processing, and we can accommodate the rewrapping of old rubber rollers.

• Printing Machinery
• Rubber

This is a rubber lining (baking) process for parts attached to machines that seal containers for snacks, tofu, cup noodles, and so on. Taking tofu containers as an example, the top of the container is sealed with a film, which is bonded to the main container using heat or pressure. To achieve this bonding, the film and the main container are subjected to high temperatures close to 200°C, and strong pressure is required to enhance adhesion, necessitating cushioning against the load. For these reasons, "silicone rubber," which possesses both heat resistance and rebound elasticity and has passed food compatibility tests, is often selected. This silicone rubber baking process requires hole machining in various parts, but it is performed without using molds (only simple jigs for silicone rubber baking).

• Food Packaging Machinery
• Rubber

We performed rubber lining processing on the inner surface of the hopper bucket provided to us. Rubber lining was requested to protect the products being transported within the factory using a cart, and we determined the processing range for the rubber lining based on the operational use of the hopper bucket and the method of product loading. We selected "wear-resistant NR with a hardness of 60°" for the rubber material, which is used on the inner surface of barrel polishing machines that experience high loads. Since the bucket body was already painted, we removed all paint using solvents and sanders, and performed first-class surface preparation through sandblasting. If any paint film remains on the rubber lining surface, it will not initiate the vulcanization bonding reaction, leading to early peeling. After sandblasting, we proceeded with the rubber lining processing following pre-treatment such as degreasing cleaning. For the bottom inner surface, we processed 60 through-holes for drainage of wash water. This time, since the various components remaining inside the bucket are extremely small, we were requested to implement improvements to prevent issues such as component clogging at the joints of the rubber lining surface, so we adjusted the conditions to ensure there would be no hindrance to use and reflected this in the actual processing. In use, there have been no issues such as component clogging, and the rubber, which has excellent wear resistance, has withstood long-term use.

• Sorting machine
• Rubber
• Trolley

This is a rubber sleeve for CIP molding. The required shape and thickness of the "rubber sleeve" vary depending on the "molded products," "molded powders," and "molding equipment." Generally, straight shapes are common, but the "rubber sleeve" we produced this time was designed with flanges at both ends for easier assembly with the equipment. Previously, it seems that the flange parts were glued, but due to insufficient strength of the adhesive and differences in elongation between the adhesive and rubber, this led to early failure, prompting a search for solutions. After contacting our company, we proposed an integrated molding solution, and we completed the production of the "rubber sleeve" with integrated molding of the flange and rubber tube parts, starting from medium-sized production. Assembly with the machinery has also become easier, and damage from the connection points has been reduced.

• Other processing machines
• Rubber

This is a mangle roll for textile machinery. Since it will be used under high-temperature and high-pressure steam conditions, it is made of a heat-resistant and durable rubber material. If the core is made of stainless steel, there is no need to consider rust on the side plates, so rubber lining on the side plates is not performed. In the case of iron rolls, if rust due to steam is a concern, rubber lining on the side plates is necessary for rust prevention. Due to the potential issues caused by carbon transfer to the fibers, black rubber (which uses carbon black as a reinforcing material) cannot be used, so it is made of white rubber.

• Textile Processing Machinery
• Rubber

This is an endless belt made of silicone rubber used in bag-making machines. This product is used by balloon manufacturers and is a quite large endless belt with an outer diameter of 1172 mm (circumference of 3680 mm). During the balloon manufacturing process, a welding process is performed at high temperatures (230°C) to bond the balloons together. This is a necessary production component for that welding process. We received an inquiry that the rubber belt used for a long time had deteriorated, but since the drawings and detailed specifications were unclear, we held discussions on the usage conditions and required specifications before proceeding with production. Based on the usage conditions, we determined that heat resistance, appropriate cushioning, and strength to withstand repeated use were necessary, so we selected "medium tear silicone rubber" as the material. A simple type (medium size) is required, but since it is a vulcanized molded product, it will be a seamless molded product with a smooth surface without joints in the rubber sheet.

• Bag making machine/slitter
• Rubber

This is a product that has undergone fluorine rubber lining on a curved roll used in spinning (shear forming) processing. Due to the nature of spinning (shear forming) products, some minor scratches are within the acceptable range, so rubber lining is not commonly performed. The product being spun this time is made of aluminum, which is prone to scratching, and the acceptance criteria for processing scratches are strict, leading to inquiries about the feasibility of processing. Since spinning processing is the preceding step, the material (aluminum plate) is exposed to high temperatures, requiring a rubber material that can withstand high temperatures. Silicone rubber and fluorine rubber were considered, but due to the need for physical strength, fluorine rubber was selected for the rubber lining. Although fluorine rubber has poor adhesion before curing and presents significant processing challenges, it has been reported that using this rubber roll resulted in effects exceeding expectations.

• Other processing machines
• Rubber

The standard belt-driven pulley (rubber roller) typically has a flat rubber surface or a crowned (convex) rubber roll. However, this product features a grooved surface. The purpose of the grooving is to prevent slipping with horizontal grooves and to prevent both slipping and wandering with double helical grooves (grooves that extend outward from the center). This rubber roller has horizontal grooves, but instead of the usual "square grooves" or U-shaped grooves, it has V-shaped horizontal grooves. While a standard groove would suffice for merely reducing slip and would lower processing costs, the decision to use a V-shaped groove, which increases processing difficulty and costs, is based on the following reasons: There are concerns about heat buildup in the belt under operating conditions, necessitating the cooling of the stainless steel belt. The V-groove shape was chosen to facilitate the flow of cooling water and to minimize water accumulation in the grooves. All listed products are made to order. Please refer to this as an example of our processing technology capabilities.

• Conveyor
• Rubber

This is a rubber bellows for vacuum devices. Normally, metal bellows are used, but in order to improve the costs associated with the bellows itself as well as the "installation and removal labor time and personnel," we have manufactured this rubber bellows for evaluation testing. The thickness is 3 to 4 mm. The size is an outer diameter of 1380 mm and an inner diameter of 1280 mm, with a maximum height of 155 mm when fully extended. Both flange surfaces have holes for bolt fastening, and the installation to the vacuum device is secured by clamping with a metallic flange and bolts. After conducting usage conditions and durability tests, we found that it meets the required functions and also clears the set durability conditions. As a result, the downtime for equipment due to bellows replacement has been significantly reduced, and the number of personnel involved in the work has also been decreased.

• Vacuum Equipment
• Rubber