Why Choose Our Elliptical Manhole
Supports multiple sizes, 300–600 mm long axis and 200–400 mm short axis
- Annual production capacity of 5000+ elliptical manholes, logistics ≤7 days, on-time delivery
- All materials support batch number tracking to ensure standard compliance and quality reliability.
- Ensure flange dimensions within ±0.2 mm tolerance for precise and consistent sealing fit
- Certifications, including ISO, DIN, ASME, meeting standards for food, pharmaceutical, and chemical industries
- Provide installation guidance and maintenance solutions to achieve rapid problem resolution
Your Reliable Elliptical Manhole Supplier in China
The elliptical manhole of OMSS adopts an optimized elliptical structure, which makes the stress distribution more uniform and reduces the risk of deformation while maintaining good structural strength. At the same time, good corrosion resistance can maintain stable and reliable structural performance in your complex working conditions.
During the manufacturing process, OMSS uses precision machining technology to strictly control the flange size to ensure good installation matching. Cutting, welding, and forming are all performed according to relevant quality standards, ensuring consistency in the structural dimensions of products in different batches for you. The manhole structure can thus seal and match the equipment more accurately, allowing your equipment to maintain stable structural strength and long-term reliability during operation.
Types of Elliptical Manholes
Welded to the equipment housing for a secure, rigid structure, ideal for long-term fixed installation.
Bolt-fastened flange design for easy removal, suitable for equipment requiring regular maintenance.
Clamp locking design for quick opening, reliable sealing, and hygienic applications.
Flange connection provides strong mechanical stability, precise fit, and easy installation.
Reinforced ring and thickened structure deliver higher pressure resistance and structural strength.
Quick-locking mechanism enables fast opening with secure sealing for frequent maintenance.
Features of Elliptical Manhole
Optimized opening provides sufficient access space, with minimal structural impact.
Standardized components simplify installation, maintenance, and part replacement.
Polished inner surface reduces media residue and simplifies cleaning.
Reinforced opening improves load capacity and maintains stability under pressure.
Convenient Installation and Maintenance
The elliptical pedestrian hole adopts a reasonable structural design, the installation process is simple and easy to use, and it can also flexibly match equipment of different structures. This facilitates the operator to enter the inside of the equipment for repair, inspection, cleaning, and maintenance. And the manhole structure opening and closing is also simple and convenient, which can reduce the time and downtime of maintenance operations of your equipment and improve production efficiency.
Reliable Seal Matching
The elliptical manhole structure is carefully controlled by finishing to strictly control tolerances, and can be used with a variety of sealing pads to closely fit the equipment, forming a stable and reliable sealing structure. Uniform force makes the whole structure stable and leak-proof. Guaranteed to keep the manhole structure stable and a stable sealing effect in the long-term operation and complex working conditions of your equipment.
Strict Quality Control
OMSS has a complete quality control system in the production process, and strictly implements quality management from raw material selection to product leaving the factory. The production team standardizes the process flow, detects and controls the dimensions of the manhole structure, welding quality, and sealing surface processing accuracy, and also checks the size and appearance before leaving the factory. Ensure that your product quality is stable and reliable.
Applications of Elliptical Manhole
In the chemical production process, various production equipment, such as reactors, storage tanks, process equipment, etc., need to be inspected and maintained regularly. The oval manhole provided by OMSS provides a reliable access to the equipment, which can help operators easily enter the equipment for inspection and cleaning.
The OMSS oval manhole can withstand pressure and also maintain a stable seal, so the safe and reliable operation of your equipment can be guaranteed.
In oil and petrochemical production systems, storage tanks, pressure vessels, and process equipment need to be in continuous operation, and therefore require regular internal inspections and maintenance.
The OMSS oval manhole energy and industrial storage tank combine to provide an outlet for equipment maintenance. Its stable structure likewise helps your industrial tank to remain sealed over long term use, reducing the risk of leaks.
In this industry, processing tanks, fermentation tanks, storage tanks, etc., need to maintain a good sanitary environment. The OMSS oval manhole facilitates routine maintenance and management of your equipment while also maintaining a reliable seal. Smooth interior surfaces and sealing structures can help reduce outside contamination and help maintain good hygiene conditions in the equipment.
In the water treatment industry, tanks and equipment need to be operated for long periods of time. The interior is prone to the accumulation of impurities and needs regular cleaning and maintenance. If the inlet design for equipment maintenance is not reasonable, it will increase the maintenance time.
The oval manhole of OMSS provides a convenient entry and exit for the equipment, facilitating inspection, cleaning, and inspection. Its construction is simple, strong, and durable.
The equipment operates on a long cycle. High requirements for maintenance efficiency and equipment reliability. The OMSS oval manhole can solve your problem, it can help the operator to enter the inside of the equipment very conveniently, overhaul maintenance. Improved maintenance efficiency and reduced equipment downtime.
This industry has extremely high requirements for the sanitary conditions of production equipment. The OMSS oval manhole can easily enter the interior of the equipment, helping your equipment to become well-maintained and well-maintained. Improve your efficiency in managing your equipment and support a clean production environment.
- Certificate of Compliance
Customer Reviews
We purchased sanitary tri clamp fittings and stainless steel ferrules from OMSS for our beverage processing system. The dimensions were accurate, the polishing was clean, and the fittings connected smoothly with our existing pipes without additional adjustment. The consistent quality helped us improve installation efficiency.
EmilyOMSS supported our custom stainless steel fitting project from drawing confirmation to final production. Their engineers provided useful suggestions on material selection and processing details. The finished components matched our requirements well and performed reliably in our food equipment applications.
JohnWe have strict requirements for surface finish and hygiene standards in pharmaceutical equipment. OMSS stainless steel fittings showed excellent workmanship, with smooth surfaces and precise machining. Their products helped us meet our equipment assembly requirements and maintain reliable production performance.
Michael
The long axis of the oval manhole can be arranged horizontally or vertically, making it suitable for use on equipment with limited space. At the same diameter, its open hole area is smaller than that of a circular manhole, which has less impact on the shell strength. When the device requires multiple entrances, the oval manhole takes up less space, making it easier to avoid key parts, and the structural layout is more flexible.
Generally, the internal surface roughness of the sanitary grade oval manhole requires Ra≤0.8μm. In applications with higher hygiene requirements, the surface roughness needs to reach Ra ≤ 0.6 μm or Ra ≤ 0.4 μm to ensure that the inner surface is smooth, clean, and prevents the growth of bacteria. The surface is generally machined by mechanical polishing and electrolytic polishing to make it smoother.
Before leaving the factory, the oval manhole is inspected for size and tolerance, and the welding quality is tested. The sealing is also checked by means of a water pressure test and an airtightness test. Finally, the surface roughness, appearance, and assembly of the oval manhole are checked to see if they meet the standards and requirements.
When selecting and manufacturing oval manholes, you can refer to: ASME pressure vessel standards, DIN industrial standards, ISO international standards, 3A food and pharmaceutical industry hygiene standards, and EHEDG.
The service life of oval manholes is affected by material quality, working environment, sealing structure, and installation quality. High temperature, high pressure, and corrosive media will accelerate the aging of materials and reduce service life.
What Is an Elliptical Manhole?
An elliptical manhole is an oval manhole structure used to connect the internal and external spaces of the device, making it convenient for people to enter the interior of the device through the manhole and perform some internal repairs, cleaning, maintenance, and other functions. The reason for the oval shape is the strength of the structure and the ease of installation. The ellipse has a longer major axis and a shorter minor axis, which is smaller than the circular loss area of the same axis. This area reduction can have a smaller impact on the structure of the equipment and facilitate human access.
How to Choose the Right Elliptical Manhole
Right Size
The structural dimensions of the oval manhole need to be determined specifically based on the structure and maintenance needs of the equipment. And ensure that operators can smoothly enter the interior of the equipment for inspection, cleaning, and repair.
Common sizes include 400x300mm, 450x350mm, 500x400mm, and 600x450mm. Large devices require the opening to be a bit larger. However, not larger is better, and the structural strength of the equipment shell must also be considered to prevent excessive opening from affecting the overall stability of the equipment.
Right Material
The material determines the corrosion resistance and service life of the manhole. Common materials are 304,304 L, and 316 L stainless steel. If your equipment needs to be exposed to highly corrosive chemical media or requires frequent cleaning and disinfection, you need to consider using 316L stainless steel to improve the corrosion resistance of your equipment.
Stress and Working Conditions
In storage tanks, fermentation tanks, and pressure vessels, there will generally be a certain working pressure inside the equipment. When the pressure inside the equipment increases, it will act on the shell and manhole structure of the equipment. If the pressure inside the device is large and the manhole structure cannot withstand it, it will affect the sealing effect and structural safety of the manhole.
So, how do you design a manhole under high pressure? Generally in this case, it is necessary to strengthen the flange or structural reinforcement to improve the pressure bearing capacity of the open hole area. It is also possible to thicken the material thickness of the manhole.
At the same time, the operating temperature inside the equipment must also be considered. Under working conditions with large temperature fluctuations or high temperatures, the material may expand thermally, or its properties may be affected by the temperature. Therefore, it is necessary to select materials with good mechanical properties and temperature resistance to ensure that the manhole can maintain good structural strength and sealing performance under different working conditions.
Suitable Sealing Structure
The sealing structure of the oval manhole affects the ability to prevent leakage. Especially in. High temperature, high pressure, and a strict hygiene working environment. Generally, its common sealing methods include flat seal and O-ring seal.
Flat seals are used in normal-pressure and low-pressure equipment environments and are used with sealing gaskets. O-type pure bees are more suitable for use in container equipment with a certain pressure. It provides good compression resilience, ensuring a good seal even after long-term use.
When choosing a sealing structure, consider the gasket material. Below is an introduction to gaskets made of different materials.
| Gasket Material | Key Characteristics | Suitable Environment | Common Applications |
| Silicone | Excellent high and low temperature resistance, flexible, and good hygienic properties | -50°C to 200°C, suitable for food-contact environments | Food processing equipment, dairy equipment, and pharmaceutical equipment |
| EPDM | Good resistance to water, steam, and many chemicals | Suitable for humid environments and cleaning processes | Water treatment equipment, food equipment, and CIP cleaning systems |
| PTFE (Polytetrafluoroethylene) | Excellent chemical stability and strong corrosion resistance | Suitable for acidic, alkaline, and corrosive media | Chemical processing equipment, corrosive environments |
| NBR (Nitrile Rubber) | Good oil resistance and stable mechanical properties | Suitable for oil-containing media | Petroleum equipment, mechanical equipment |
| FKM (Fluoroelastomer / Viton) | Excellent resistance to high temperature, oil, and chemicals | Suitable for high-temperature and chemical environments | Chemical equipment, high-temperature sealing applications |
Industry Application Selection
What type to choose specifically needs to be determined in conjunction with your usage scenario.
Food, beverages, pharmaceuticals, and other industries with high hygiene requirements. The manhole needs to be made of stainless steel. And the internal surface is smooth, which can ensure that there are no dead corners inside, facilitate cleaning and disinfection, and prevent the growth of microorganisms. It is recommended to choose the quick-opening structure for easy access to the interior for cleaning.
In industries such as the chemical industry and environmental protection, equipment may need to be exposed to highly corrosive media to operate under complex working conditions, so the focus needs to be on the corrosion resistance and sealing reliability of manholes. In these applications, 316 stainless steel and fluororubber seals are a common combination.
If it is necessary to install on a pressure vessel or pressure-bearing equipment, the manhole design must comply with relevant pressure vessel standards to ensure the structural safety and sealing performance of the equipment.
