Polyurethane Washers

Brand :

MISUMI

Caution

Product Description

This is an economy item, The price is cheaper than the MISUMI standard product.

Product Overview

Polyurethane washers are effective in preventing workpiece scratches and cracking during fastening, as well as providing cushioning, shock absorption, and vibration resistance for impact parts.
Transparent polyurethane serves a special, unobtrusive role as an exterior part during assembly.

Dimensional Drawing

Tolerance measurement environment: Temperature 23±2°C, humidity 40 to 80%.

Standard Tolerance
D Tolerance

D	Tolerance
6 to 40	±0.2
41 to 60	±0.3
61 to 100	±0.4

Precision Grade Tolerance
V Tolerance

V	Tolerance
2 to 50	0 to 0.1
51 to 80	0 to 0.2

Material Specifications

Shape	Normal	Precision	Material	Hardness	Color	Standard	Customizable type
Standard	E-URWS	E-UAWS	Standard urethane (ether type urethane)	Shore A95	(1) Natural Color (Transparent)	Outer Diameter D6 to D60 Inner Diameter V2 to V40 Thickness T1/2/3/5/10	Outer Diameter D6 to D30 Inner Diameter V0 to V26 Thickness T1 to 10 (V ≤ D-4)
	E-URWH	E-UAWH	Standard urethane (ether type urethane)	Shore A90
	E-URWM	E-UAWM	Standard Polyurethane (Ester-based Polyurethane)	Shore A70
	E-URWL	-	Standard Polyurethane (Ester-based Polyurethane)	Shore A50
	E-URHWH		Heat-resistant urethane	Shore A90	(3) Brown
	E-UREWH		Wear-resistant urethane	Shore A90	(4) Dark Brown
	E-UREWM		Wear-resistant urethane	Shore A70	(4) Dark Brown
Customizable type	E-URFS	E-UAFSN	Standard urethane (ether type urethane)	Shore A95	(1) Natural Color (Transparent)
	E-URFH	E-UAFH	Standard urethane (ether type urethane)	Shore A90
	E-URFM	E-UAFM	Standard Polyurethane (Ester-based Polyurethane)	Shore A70
	E-URFL	-		Shore A50
	E-URFY			Shore A30
	E-URFHE		Antistatic Urethane	Shore A90	(2) Grey
	E-URFME			Shore A70
	E-URFLE			Shore A50
	E-URHFH		Heat-resistant urethane	Shore A90	(3) Brown
	E-UREFH		Wear-resistant urethane	Shore A90	(4) Dark Brown
	E-UREFM		Wear-resistant urethane	Shore A70	(4) Dark Brown
	No hole when V0.

Polyurethane will yellow over time, but its properties will not change.

Details of Various Polyurethane Characteristics Enter Here.

Tolerance measurement environment: Temperature 23±2°C, Humidity 40 to 80%.

For the characteristics of conductive polyurethane, please refer to the characteristics table on the right.

■ Electrostatic Polyurethane Properties

Volume Resistivity	2.1 × 108 Ω·cm
Surface Resistivity	4.0 × 109Ω

(Test conditions: Temperature 30°C, Humidity 60%)

Other characteristics are the same as polyurethane of the same hardness.

■ Polyurethane Washer Color Reference

Natural Color (Transparent)	Natural	Dark Brown	Brown	Light Brown	Grey	Mouse Grey

Polyurethane is subject to color variation; the above colors are for reference only.

Specification Table

■ Standard

Part Number			V													T
Type		D	Selection													Selection
Normal		6	2													1	2	3
E-URWS	(Standard Shore A95)	8	2	3	4											1	2	3
E-URWH	(Standard Shore A90)	10		3	4	5	6									1	2	3	5
E-URWM	(Standard Shore A70)	12			4	5	6	8								1	2	3	5
E-URWL	(Standard Shore A50)	15			4	5	6	8	10							1	2	3	5
E-URHWH	(Heat Resistant, Shore A90)	20				5	6	8	10	12								3	5	10
E-UREWH	(Wear-resistant, Shore A90)	25				5	6	8	10	12	16	20						3	5	10
E-UREWM	(Wear-resistant, Shore A70)	30				5	6	8	10	12	16	20						3	5	10
Precision		35						8	10	12	16	20	25						5	10
E-UAWS	(Standard Shore A95)	40						8	10	12	16	20	25	30					5	10
E-UAWH	(Standard Shore A90)	50						8	10	12	16	20	25	30					5	10
E-UAWM	(Standard Shore A70)	60								12	16	20	25	30	40				5	10

■ Freely configurable

Part Number				D	V	T
Type				Can be specified down to 1 mm increments	Can be specified down to 1 mm increments	Can be specified down to 0.5mm increments
Normal				6~15	0 (No Hole Type) 2–26 (V ≤ D-4)	1.0~5.0
E-URFS	(Standard Polyurethane Shore A95)	E-URFHE	(Electrostatic Polyurethane Shore A90)
E-URFH	(Standard Polyurethane Shore A90)	E-URFME	(Electrostatic Polyurethane Shore A70)
E-URFM	(Standard Polyurethane Shore A70)	E-URFLE	(Electrostatic Polyurethane Shore A50)			5.5~10.0
E-URFL	(Standard Polyurethane Shore A50)	E-URHFH	(Heat-resistant Polyurethane Shore A90)
E-URFY	(Standard Polyurethane Shore A30)	E-UREFH	(Wear-resistant Polyurethane Shore A90)
		E-UREFM	(Wear-resistant Polyurethane Shore A70)	16~30		1.0~5.0
Precision
E-UAFSN	(Standard Polyurethane Shore A95)
E-UAFH	(Standard Polyurethane Shore A90)					5.5~10.0
E-UAFM	(Standard Polyurethane Shore A70)

No hole for V0

Product Features

Feature 1: Compared to rubber, polyurethane offers a wider range of hardness options, is softer and more elastic, and has a certain degree of airtightness. (Please refer to the following hardness table)
Feature 2: Urethane has excellent mechanical strength and is more widely used to prevent scars and cracks when fastening brittle objects such as glass and acrylic.
Feature 3: Not prone to transmitting vibration and sound, and when used with fastening screws, it can provide a certain degree of cushioning effect during fastening.
Feature 4: Polyurethane has low dust generation, and since it does not contain carbon, it is a material that is not prone to color transfer. (*Natural color only)
Feature 5: A wide variety of products are available to suit different operating conditions.

Product Category Details Enter Here

■ Hardness Table

Material	A95	A90	A70	A50	A30
Urethane	●	●	●	●	●
Nitrile Rubber	×	×	●	●	×
Chloroprene	×	×	●	×	×
EPDM Rubber	×	×	●	×	×
Silicone Rubber	×	×	●	●	×
Fluororubber	×	×	●	×	×
Butyl Rubber	×	×	●	×	×

Precautions

(1) About urethane discoloring
Urethane will darken its color by absorbing UV rays or illuminating light. This phenomenon is called yellowing. But it does not affect its physical properties, please fully understand when using it.

New urethane	Yellowed urethane

(2) Hydrolysis characteristics of urethane
If urethane is used for a long time in a moist or humid environment, it will be hydrolyzed and deteriorated.
It is recommended to manage the temperature and humidity of the warehouse and operating environment in areas with high humidity to extend the service life of the product.

(3) Changes in the state of the product after hydrolysis
· The surface of the polyurethane becomes sticky
· Pressing lightly with a fingernail leaves irreversible marks
· The hardness of the polyurethane decreases
· The polyurethane dries and cracks, easily disintegrating into powder

Hydrolyzed urethane

(4) Urethane dimension change
Urethane dimension will change with the surrounding temperature, but the amount of change is not large, and it can be restored to its original dimension after a few hours at room temperature.

Example of Use

Example of Use①

Role of Product

■ Positioning and Fastening Mechanism

Use polyurethane washers to prevent fastener scratches and cracking
While adjusting the height, it also reduces vibration during workpiece operation.

The dimension table includes dimensional tolerances, polyurethane yellowing and discoloration, and polyurethane rubber products

Example of Use②

Role of Product

■ Press-fit Fixing Mechanism

Provides special effects in cushioning and shock absorption for impact parts, and is particularly effective in vibration prevention.

Polyurethane sole is made of polyvinyl chloride. Rigid polyurethane foam coating.

Related Industries

Electronic		Automotive

Smart phone		Semiconductor

(Economy series) Urethane plate Customizable type	Stopper bolt	(Economy series) Urethane vibration damping material Customizable type

Typical model: E-UTSN8-300	Typical model: UST3-15	Representative Model: E-AXFME-D35-L51-V23