Introduction: CT and X-Ray tables need lightweight structural materials that support the patient while preserving a clear imaging path through the complete table assembly.
A CT or X-Ray table must carry patients and accessories, maintain its geometry during movement, and provide a controlled path for imaging. These requirements connect structural design with imaging performance. A lightweight material or a material described as having good X-Ray transmission is only one part of the table assembly. Rifeng PMI Foam refers to the PMI-based structural foam category represented here by Rifeng W PMI Foam, a closed-cell rigid core with a medium cell size. The listed nominal density range is 32 to 200 kg/m³, and the product is identified for medical technology uses including X-Ray and CT examination tables. The engineering question is how this foam can fit within a composite table and how application descriptions, transmission information, and medical device evaluation relate to one another.
The table surface needs enough stiffness to support a patient without excessive deflection. It must preserve positioning accuracy while the patient remains stationary or moves through a scanning position. Geometry, support locations, movement, cleaning requirements, attachment points, and repeated loading all influence the structural design. Lower structural weight can reduce moving mass and support easier handling, while compression resistance, shear performance, face-sheet stiffness, bonding, and dimensional stability remain important. Imaging introduces a separate design requirement. In an X-Ray system, the beam travels through the table and patient toward a detector. In CT, the table moves through the scanner as images are collected from multiple angles. The table therefore occupies a planned section of the imaging path. Its construction should limit unnecessary attenuation and local image features while retaining the support required by the equipment. This combination explains the use of composite sandwich constructions. Thin outer skins can work with a lightweight core to form a stiff panel without using a thick solid section throughout. The complete assembly may include face sheets, adhesive layers, protective surfaces, inserts, rails, fasteners, bearings, and a support frame. Core thickness and panel geometry influence bending stiffness, deflection, edge stability, and space for mechanisms. A suitable core in an unsuitable thickness or laminate arrangement will produce a different result from the same core in a validated table design.
A PMI foam core normally sits between stronger outer skins or face sheets. Increasing the separation between the skins can improve panel bending efficiency, while the core maintains that separation and transfers shear between the faces. The outer skins carry much of the surface and bending load; the core contributes to shear transfer, local support, and the overall lightweight form. MIT OpenCourseWare provides educational material on composite materials and related structural principles that help explain this sandwich construction. Rifeng W PMI Foam is described as a closed-cell rigid structural foam core based on Polymethacrylimide (PMI), with a medium cell size. The product information lists medical technology, X-Ray tables, and CT examination tables among its application directions. It also identifies VARI, RTM, thermal forming, and CNC machining as relevant composite processing directions. These facts make the material a candidate for technical evaluation in lightweight table structures and shaped composite panels. The listed nominal density grades are 32, 52, 75, 110, and 200 kg/m³. The product data includes typical compression, tensile, flexural, shear, elastic modulus, and heat deformation resistance values. Typical compression strength rises from 0. 40 MPa for 32W to 9. 65 MPa for 200W, while typical shear strength rises from 0. 40 MPa to 5. 00 MPa across those grades. Such figures help compare the listed grades. They remain material values associated with stated grades and test methods, rather than finished table ratings. The medium cell structure also has a manufacturing relationship with resin uptake and face-sheet bonding. The product description presents a balance between resin absorption and bonding, and compares resin absorption with the Rifeng WH series. This factor can matter in VARI or RTM because excess resin entering the core can increase mass and alter the intended laminate build. Bond quality still depends on the prepared surface, adhesive or resin system, pressure, temperature, and process control. Cell size alone cannot determine the finished bond.
X-Ray or CT access is determined by the full material path. The beam can pass through a surface coating, face sheet, adhesive film, foam core, inserts, hardware, and support components before reaching the detector. Each layer may contribute attenuation or create a local feature in the image. Rails, openings, moving mechanisms, and metal fittings can also affect clear access. A description of good X-Ray transmission is therefore useful as an early material-selection signal. Final imaging behavior belongs to the assembled table and its operating geometry. Evaluation should consider the thickness and composition of every layer in the beam path, table position, scanner geometry, and the imaging requirements of the finished equipment.
The core must work as a structural component as well as an imaging-path material. Compression strength is relevant where loads pass through the panel or where supports contact the table. Shear strength and shear modulus influence load transfer between the face sheets. Thickness affects stiffness, deflection, edge behavior, and the space available for inserts. Grade selection should connect the listed density and typical values with span, support conditions, load direction, patient weight range, movement, and repeated use. A lower-density grade may suit a weight target, while a higher-density grade may provide greater resistance to local compression or shear. The appropriate choice depends on the complete geometry and load case. Each Rifeng W value should be read with its grade, unit, test method, and typical-value status.
An application description identifies a setting in which a material may be considered. Transmission data describes material behavior under defined measurement conditions. Medical device evaluation addresses the finished table, its intended use, risks, performance, manufacturing controls, and applicable regulatory requirements. A CT table forms part of a medical imaging system. Its design can affect patient support, positioning, movement, image access, mechanical safety, cleaning, and interaction with the scanner. These questions belong to device and system development. The FDA Medical Device Development Tools program describes tools and methods used within medical device development and evaluation, while the FDA Recognized Consensus Standards database provides a route for identifying standards relevant to a device and development activity. The same distinction applies to supplier quality information. An ISO 9001:2015 quality management system can be relevant to supplier assessment, but it represents a different type of evidence from medical device authorization or equipment approval. Product applications, company credentials, typical material data, and quality-system information should each retain their proper meaning. A practical evaluation sequence begins with the table geometry and intended imaging path. The engineer can then compare core grades, thicknesses, and typical structural properties, followed by review of the face-sheet, adhesive, insert, and support design. Assembly-level transmission measurements, mechanical testing, risk assessment, manufacturing controls, and regulatory documentation connect the material candidate to the finished medical device.
PMI foam core can be considered for CT and X-Ray tables when a lightweight composite sandwich structure must combine stiffness, support, shaping flexibility, and an unobstructed imaging path. Rifeng W PMI Foam is a closed-cell rigid PMI core with a medium cell size, five listed nominal density grades, typical mechanical data, and stated medical technology, X-Ray, and CT table applications. Three information levels should remain distinct: the listed application, the material’s structural or transmission data under defined conditions, and the medical device evaluation of the finished table. This approach supports disciplined material screening while keeping device-level performance, assembly validation, and regulatory documentation within the appropriate engineering process.
A：PMI foam core may be considered when a table requires a lightweight sandwich structure with useful stiffness, compression resistance, shear performance, and shaping flexibility. Positioned between composite face sheets, the core can help form a rigid panel without using a heavy solid section throughout. Rifeng W PMI Foam is listed for X-Ray and CT examination table applications and covers nominal densities from 32 to 200 kg/m³.
A：An X-Ray application description identifies a potential material use. Medical device compliance is established through evaluation of the finished table, its intended use, imaging performance, structural safety, manufacturing controls, risk management, and applicable regulatory standards. The application statement supports initial technical investigation, while device-level testing and documentation support the medical assessment.
A：Relevant factors include core density, thickness, compression strength, shear strength, shear modulus, face-sheet stiffness, adhesive behavior, inserts, support locations, and the complete material stack in the imaging path. Patient loading, movement, dimensional stability, cleaning requirements, and scanner geometry also affect the design. Rifeng W typical values should be read with the corresponding grade, units, and test methods.
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