Japanese Cast Steel OS&Y Gate Valves for Industrial Plant Isolation

Nichiboku's industrial Insights

Introduction

Industrial piping systems require dependable isolation points for maintenance, equipment protection, process shutdowns, and operational control. (Japanese cast steel gate valves).

The Makimura cast steel external-thread gate valve is an outside screw and yoke — OS&Y — rising-stem valve designed for full-open or full-closed isolation service in industrial piping systems.

Makimura manufactures this valve series with JIS and ASME flanged configurations for applications in steel mills, chemical plants, power-generation facilities, and other process industries.

Makimura Seisakusho OS&Y gate valve featuring cast steel construction, available in JIS 10K, JIS 20K, ASME Class 150, and ASME Class 300 flanged configurations, ideal for industrial applications.

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Product Identification: Japanese cast steel gate valves

Identification Parameter	Confirmed Information
Manufacturer	Makimura Mfg. Co., Ltd.
Product Category	Cast Steel Gate Valve
Stem Configuration	External thread, OS&Y rising stem
Operation	Manual handwheel
Connection	Flanged
Standard Body Material	ASTM A216 WCB cast steel
Nominal Size Range	50A–300A / 2–12 inches
Primary Function	Full-open or full-closed pipeline isolation

The promotional image identifies the product category and external configuration. However, the exact catalog code and pressure class cannot be determined from appearance alone.

Catalog Models and Flange Standards

Catalog Code	Flange Configuration	Nominal Size Range
MSC-10GA	JIS B2220 10K	50A–300A
MSC-150GA	ASME B16.5 Class 150	2–12 inches
MSC-20GA	JIS B2220 20K	50A–300A
MSC-300GA	ASME B16.5 Class 300	2–12 inches

The catalog references JIS B2071, API 600, and ASME B16.34 as applicable valve standards.

Flange configurations outside the listed standards may be manufactured upon request, subject to technical evaluation by Makimura.

OS&Y Rising-Stem Configuration

In an OS&Y gate valve, the stem threads are positioned outside the valve body. The stem rises as the valve opens, providing a visible indication of the valve position.

This configuration supports:

• Clear visual confirmation of open or closed position

• External access to the threaded stem

• Separation of the stem threads from the process fluid

• Manual isolation of industrial piping

• Maintenance planning and operational inspection
  

Gate valves are intended primarily for isolation. They should normally be operated either fully open or fully closed rather than used for continuous throttling or flow regulation.

Confirmed Standard Construction

Component	Catalog Material
Body	ASTM A216 WCB
Bonnet	ASTM A216 WCB
Yoke	ASTM A216 WCB
Stem	ASTM A182 F6a
Seat Ring	ASTM A105N with faced seating surface
Gasket	SUS304 and graphite
Packing	Graphite
Bonnet Bolting	ASTM A193 B7 / ASTM A194 2H

Disc and seating-face materials vary according to the selected catalog code and pressure class. The exact trim specification must therefore be confirmed against the required model rather than generalized across the complete series.

Makimura Seisakusho Japanese cast steel OS&Y gate valve with rising stem, expertly installed in an industrial piping system, showcasing durable flanged connections.

Industrial Applications

Makimura cast steel gate valves may be evaluated for isolation service in:

• Steel manufacturing facilities

• Chemical and petrochemical plants

• Power-generation facilities

• Oil and gas processing systems

• Industrial utility piping

• Steam and process-fluid systems

• Plant maintenance and replacement projects
  

Final suitability depends on the process fluid, pressure, temperature, corrosion conditions, piping standard, material requirements, and operating cycle.

Pressure and Temperature Verification

A flange class alone does not define the complete operating limit of the valve.

Pressure-temperature suitability must be evaluated according to:

• Selected catalog code

• Body and trim materials

• Process fluid

• Design pressure

• Operating pressure

• Design temperature

• Operating temperature

• Applicable piping standard

• Required inspection and certification scope

The valve should not be selected only by nominal size or visual similarity.

High-Pressure Gas Certification

Makimura indicates that configurations requiring Japanese high-pressure gas certification may be accommodated upon request.

This does not mean that every standard valve is automatically certified.

The requirement must be declared before quotation so the manufacturer can evaluate:

• Exact valve model

• Pressure class

• Materials

• Manufacturing specification

• Inspection procedure

• Testing requirements

• Required certification documents
  

For projects outside Japan, compliance with the regulations applicable in the destination country must be evaluated separately.

Information Required for Technical Selection

Selection Requirement	Information to Provide
Valve Function	Isolation service and operating purpose
Process Fluid	Liquid, gas, steam, or chemical composition
Nominal Size	Required pipe diameter
Connection	JIS or ASME flange standard and class
Pressure	Normal operating and design pressure
Temperature	Normal operating and design temperature
Materials	Required body, trim, stem, seat, and gasket materials
Operation	Manual operation or required actuation
Dimensions	Face-to-face and installation restrictions
Compliance	Applicable standards, inspection, and certification
Replacement Unit	Existing model, drawing, nameplate, and photographs
Quantity	Required number of valves

Replacement Valve Verification

A replacement gate valve must be verified beyond its nominal diameter and flange rating.

Technical review should confirm:

• Complete manufacturer and catalog code

• Pressure class

• Face-to-face dimension

• Flange drilling and facing

• Body and trim materials

• Stem and bonnet configuration

• Operating pressure and temperature

• Required shutoff direction

• Available installation clearance

• Inspection and documentation requirements

The four catalog codes have different flange dimensions, overall dimensions, weights, and pressure classifications. They should not be treated as automatically interchangeable.

International Sourcing from Japan

Nichiboku supports international end users, maintenance teams, engineering companies, and industrial procurement departments requiring Makimura valves for defined plant applications and replacement projects.

Support may include:

• Product and catalog-code identification

• Technical specification coordination

• Replacement requirement evaluation

• Manufacturer quotation management

• Export documentation

• International supply from Japan
  

View the Makimura product profile:

https://www.nichiboku.com/japanese-industrial-products/makimura-mfg

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Review Nichiboku’s virtual catalogue of Japanese industrial equipment and components for plant maintenance, replacement requirements, and defined industrial projects worldwide.

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